USE WITH CARE
MANAGING AUSTRALIA'S NATURAL RESOURCES IN THE 21ST CENTURY
There is no end to the writing of books.
BOXES AND TABLES ix
MAPS AND FIGURES xiii
1. LEARNING THE HARD WAY 3
2. TAKING STOCK: THE NATURAL ASSETS OF A SMALL CONTINENT
3. GAZING OUT TO SEA: THE INTERNATIONAL ENVIRONMENT 47
4. PATTERNS IN THE DUST: CURRENT LAND USE 58
5. THUMBSUCKING: OPPORTUNITIES AND IMPERATIVES 107
6. TECHNOLOGY AND RESOURCE MANAGEMENT 175
7. COPING WITH GOD AND HUMAN: NATURAL AND OTHER DISASTERS
8. HOW MANY PEOPLE? HOW MANY PETAJOULES? 214
9. THE LAND OWNERSHIP QUESTION 229
10. IS ANYBODY IN CHARGE OUT THERE? 253
11. STEPPING BACK FOR A LOOK 287
Box 2.1 Causes of extinction of arid zone mammals 22
Box 2.2 Major land-degradation processes 29
Box 2.3 Major sources of natural system disturbance 40
Box 4.1 The many effects of climatic change on the coastal zone 86
Box 4.2 Australia's world role as a mineral producer 94
Box 4.3 New methods in mining 96
Box 4.4 Reducing vulnerability to fluctuating commodity prices 100
Box 5.1 Some consequences of a doubling of Australia's population 108
Box 5.2 Why erosion may not be so bad 110
Box 5.3 Herbicide residue problems 112
Box 5.4 Goals of the National Soil Conservation Strategy 113
Box 5.5 Some air-pollution problems 113
Box 5.6 Checklist of reasons for conserving species 119
Box 5.7 What is a national park? 122
Box 5.8 Conservation covenants 123
Box 5.9 Essence of a conservation strategy 125
Box 5.1 Approaches to solid-waste management 127
Box 5.11 Lowering the physical impact of tourism 129
Box 5.12 Places to enjoy 131
Box 5.13 Principles for developing a system of recreation areas 132
Box 5.14 Some remaining wilderness areas 132
Box 5.15 Comparative and competitive advantages 134
Box 5.16 Some agricultural products with growth prospects 136
Box 5.17 Focal issues for national forest policy 143
Box 5.18 Locking up carbon in trees 146
Box 5.19 Farming the sea 148
Box 5.20 Competitive strengths of Australian mariculture 149
Box 5.21 The image processor 150
Box 5.22 Looking high an3d low for an export strategy 152
Box 5.23 Why is infrastructure important? 153
Box 5.24 Deficiencies in the Australian rail system 154
Box 5.25 Components of a national transport plan 158
Box 5.26 Improving environmental impact statements 161
Box 5.27 Complements to environmental impact assessment 162
Box 5.28 The solution to pollution is not always dilution 163
Box 5.29 Improving cost-benefit analysis 165
Box 6.1 Some Australian advances in remote sensing 184
Box 6.2 Major functions of natural systems 187
Box 6.3 Science piggybacks on technology 189
Box 7.1 Policies for coping with drought 198
Box 7.2 Approaches to reducing bushfire damage 200
Box 7.3 Problems with elusive and lingering chemicals 204
Box 7.4 Ideas for managing agricultural chemicals 204
Box 7.5 A program for responding to sea-level rise 210
Box 8.1 Study areas for the 1972--75 growth centres program 218
Box 8.2 Candidate themes for a national urban-development strategy 219
Box 8.3 Received objectives of national energy policy 221
Box 8.4 Why capping energy use might become an idea in good currency 225
Box 9.1 Types of property rights 233
Box 9.2 Benefits claimed for site rating 236
Box 9.3 Candidate areas for regional planning 245
Box 10.1 Objectives of the National Conservation Strategy 256
Box 10.2 The complexities of sustainable development 257
Box 10.3 What is a conservationist said Alice? 258
Box 10.4 Brundtland's sustainable development strategy 258
Box 10.5 Disadvantages of regulatory solutions to pollution problems 265
Box 10.6 Approaches to valuing non-market goods 266
Box 10.7 Market-oriented approaches to environmental management 268
Box 10.8 Achieving legitimacy in public decisionmaking 271
Box 10.9 What are values? 273
Box 10.10 Some successful Australian social technologies 276
Box 10.11 Components of a social learning sysem 277
Box 10.12 Emerging social technologies 281
Box 10.13 Improving social technologies 282
Box 11.1 The broad instruments of public policy 288
Box 11.2 Chronic problems of resource management 289
Box 11.3 Five challenges for Australian resource scientists 295
Table 2.1 Three per cent of Australia is wetlands
Table 2.2 Trying to establish the current rate of forest clearing
Table 2.3(a) Forms of degradation in non-arid areas of Australia, 1975
Table 2.3(b) Forms of degradation in arid areas of Australia, 1975
Table 2.4 Land degradation in New South Wales, 1988
Table 4.1 Regions of the Ecumene (1981)
Table 4.2 Land use in Australia---the broad picture
Table 4.3 Average annual value of production (1983--87) of 13 product groups in 10 agricultural regions
Table 4.4 Intensively cropped regions of Australia
Table 4.5 Vegetation change in the Murray-Darling Basin
Table 4.6 Numbers of species of amphibia, reptiles, birds and mammals in the major faunal regions of Australia
Table 4.7 Quantities of fisheries products
Table 4.8 Recent changes in coastal-zone population
Table 4.9 Australian percentages of Western world mineral production
Table 4.10 Commodities as percentages of total exports 1987/88
Table 4.11 Gross Domestic Product, imports and exports of goods, OECD nations, 1986
Table 5.1 Impact on total agricultural production of a 25% fall in zonal production
Table 8.1 Two projections of national population
Table 8.2 The energy consumption league table
Table 10.1 Comparison of three economies
Table 11.1 Spreading it out thin
Map 1.1 Competing land uses 5
Map 2.1 Folk regions of Australia 11
Map 2.2 A minimally drained continent 11
Map 2.3 The Indo-Australian plate 12
Map 2.4 Physiographic regions of Australia 12
Map 2.5 Intrinsically productive soils 12
Map 2.6 Agro-climatic zones (after Papadakis) 12
Map 2.7 Human comfort zones 13
Map 2.8 Winds of Australia 13
Map 2.9 Cyclone hazard regions 13
Map 2.10 Rainfall and rainfall variability 14
Map 2.11 Major concentrations of wetlands 15
Map 2.12 Groundwater resources of Australia 16
Map 2.13 Simplified vegetation map of Australia 17
Map 2.14 Mineral-bearing regions 19
Fig. 2.1 Occurrence of silver top ash in relation to altitude and rainfall in the forests of south-east Australia
Fig. 2.2 Past and present distributions of some Australian mammals
Fig. 2.3 The dryland salinisation process
Fig. 2.4 Block diagram of a land system
Fig. 2.5 Cross-section of a central Australian landscape
Fig. 2.6 The El Nino process
Fig. 5.1 Some forecasts of Australian oil production
Fig 8.1 Australia's refugee intake compared to other countries
Fig. 10.1 Sustainable resource use
Fig. 10.2 Sustainable net domestic product
ABS Australian Bureau of Statistics
ACF Australian Conservation Foundation
AEAM Adaptive Environmental Assessment and Management
AFZ Australian Fishing Zone
AGPS Australian Government Publishing Service
AIDA Analysis of Inter-connected Decision Areas
ARIS Australian Resources Information System
AUSLIG Australian Surveying and Land Information Group
BTKM billion tonne km
CSIRO Commonwealth Scientific and Industrial Research Organisation
EIA Environmental impact assessment
EIS Environmental impact statement
ENSO El Nino-Southern Oscillation (perturbation)
GATT General Agreement on Tariffs and Trade
GDP Gross Domestic Product
ICOMOS International Council on Monuments and Sites
LGA Local Government Area
M-DB Murray-Darling Basin
MFP Multi-Function Polis
NFF National Farmers' Federation
NSW New South Wales
OECD Organisation for Economic Co-operation and Development
SA South Australia
UNESCO United Nations Educational, Scientific and Cultural Organisation
WA Western Australia
All my working life, I have been paid well to enjoy myself studying the natural resources of Australia. My first jobs were as an agricultural advisory officer and then as a commercial agricultural consultant in western Victoria. After some years overseas, I returned to the CSIRO Division of Land Research at the time when they were just winding down their massive program for mapping the natural resources of sparsely settled Australia. It was my job to evaluate the economic prospects for commercial cropping revealed by the Division's research programs in the Kimberleys and the Northern Territory. From that blooding I developed a lasting interest in land use policy and land use planning which has since led me to places as far apart as the Great Barrier Reef Marine Park and north-west Tasmania.
My attitudes to land and its use have changed since I went forth thirty years ago to carry the good news about potash to a breathlessly expectant farming community. Certainly I loved being in the bushland of the Otway Ranges but I never blinked as thousands of acres of native forest fell to the chains and dozers to create the Heytesbury closer settlement scheme. I was more concerned about how to make clover grow in that newly naked landscape.
I still appreciate well-managed farmland today but my heart bleeds a drop when I see a more or less natural area being drained or felled or burnt or levelled to let two blades of grass grow where none grew before. `Surely true wealth lies in being able to let it be, in not being forced to use resources intensively?' I now ask. Like all our natural systems, areas which remain undeveloped are still going to have to change and adapt to powerful new forces even if no one touches them. At very least, they will have to adapt to alien plants and invading animals brought here by Europeans. They may have to adapt to major climatic changes.
Nowadays I work in the CSIRO Division of Wildlife and Ecology. It is an environment where one is constantly aware of resource utilisation battles between ecological conservatives and economic conservatives. The Division itself tries to stay neutral and provide disinterested information which, at least, will allow extreme positions on either side to be challenged. I too am neutral; not because I do not care, but because I can appreciate the values promoted by both the greenies and the brownies. My colour is olive.
Central to this book is my belief that it is still possible to have an Australia where the values of all but the most extreme materialists and extreme environmentalists can be satisfied. Acts of desperation are not yet necessary. This is not to say that I am optimistic that this scenario can be or is likely to be achieved. A scenario is a description of a plausible future; if I think that the idea of Australia as a good place to live can survive well into the next century, it is up to me to argue how this might believably come about. It will be inch by inch, step by step, not in one miraculous leap. I will still be sad for things that we have unnecessarily lost---great Huon pines and Karris, Tasmanian tigers, Sherbrooke lyrebirds, Aboriginal languages, Barmah forest (almost), Lake Pedder, coastline access ...
I have chosen to direct this book at the next hundred years because that is intellectually liberating. If we look ten or twenty years ahead, common sense screams out that significant changes in values are not possible, that the States and the Commonwealth will still be smiting away at each other in territorial battles and that the juggernaut of short-sighted market-driven change will be rolling on regardless. All things are possible in a hundred years though, aren't they? No one can pretend to see that far ahead and one can be certain that any medium-to-long-term scenario will be massively wrong. It does not matter; I am really trying to look at problems and possibilities which will spring fairly directly from today's Australia over the next several decades but without the shades of common sense to restrict my vision.
What I have to offer in the `struggle for perspective' is some accumulated technical knowledge, a little controlled passion and a handful of variously acquired insights on some of the reigning issues in the resource use-resource management debate. It is not much. But I once asked Professor Geoff Leeper, doyen and scourge of several generations of Melbourne University agricultural science students, what I could do to change the world. `The best you can do is tell people how you see things' he said.
A comment on language
Encountering words like proactive which are somewhat new and not found in basic English frequently rouses otherwise intelligent and sensible people to a fury. English has a large and dynamic vocabulary for succinctly and accurately expressing an evolving multitude of ideas. I ask the reader to accept that every word I use has been chosen because I think it is the best word. I have tried to use a minimal number of specialist scientific terms but, apart from that, if a word is unfamiliar, it does not mean that I am being pretentious, it means that you should look it up.
I have mostly avoided using Latin names for plant and animal species in favour of standard common names, not that these are all that standard. My attempt to avoid the repeated use of `his or her' is `hir'.
Jenny Clark is an expert in the natural resource-environmental literature and she has not only found the books and references I wanted, but suggested others which turned out to be extremely useful. I am grateful to Brian Walker, Chief of the Division of Wildlife and Ecology, for his willing acceptance of the idea that I devote time to completing this book. Ninon Geier has imposed a neat uniform style on a diverse suite of maps, some of which were originally computed by Nina Wood. Julia Tanguy and Venetia Nelson from New South Wales University Press have managed to be both warmly supportive and coolly professional during all the rites of passage a manuscript must undergo. Several colleagues have given time to read and comment on portions of the manuscript: John Patrick `Bottom line' Makeham who tried hard to rein in my appetency for polysyllabic prosification; Mike Young, who reminded me to think like an economist---when absolutely necessary. Finally, I want to thank Doug Cocks for doing all the typing.
1. LEARNING THE HARD WAY
Australia is the flattest, harshest, ugliest land in the world.
Natural factors affecting land use
Australia's outstanding natural attributes
Apart from size (the sixth largest
country in the world) and location (isolated in the southern oceans),
Australia's outstanding natural attributes are a dry climate and a geologically
ancient land surface. Taken together,
these factors have produced a resource complement which, by global standards,
is noteworthy in at least the following ways
* a climate characterised by low variable rainfall, strong climatic gradients between coast and inland, droughts and floods
* generally unproductive soils---infertile, shallow, stony and salt-prone
* limited occurrences of perennial surface water and snowfields
* a long diverse coastline
* a featureless landscape with little mountainous terrain
* a rich and unique complement of native plants and animals
* limited areas of (a) natural grassland and (b) relatively unproductive forests.
Some of the land use implications of this situation have been
* intensive settlement has only been possible over a modest fraction of the country
* large forestry activities have not been possible
* intensive agriculture has only been possible in the wetter fringes of the country
* methods of adapting European agricultural systems to the Australian environment have had to be developed de novo
* the coastline and inland waters have become the foci for recreation activities
* ground transport systems have been slow to develop over the country's long distances and have been of poor quality
* production of minerals for export has been and continues to be an important economic activity
Some spectacular historical misjudgments
Because European settlers had to learn
to understand the Australian environment from scratch, it is
inevitable that they should have made misjudgments about the consequences of various land management practices. Among the more spectacular of these have been misjudgments about
* long-term livestock-carrying capacity and crop yields in inland areas
* the impact of introducing feral animals (particularly rabbits and foxes) on pasture and range productivity
* the effects of introducing exotic plants destined to become weeds, e.g prickly pear
* the unforeseen consequences of excessive clearing of timber, e.g. salinisation, erosion, woody regrowth
* the effects of uncontrolled irrigation, e.g. salinisation of soil and water
* the susceptibility of bare soil to water and wind erosion
* the risks and consequences of floods and fires.
Such technical misjudgments have been an important factor in explaining Australia's changing land use patterns since white settlement. While many individuals have paid dearly for their own misjudgments, the social costs of individual mistakes have dwarfed the private costs in many cases; salinisation of the Murray Basin is a national disaster as well as a disaster for farmers forced off their land.
Social and institutional factors affecting land use
Rigid social attitudes to land
In addition to `technical misjudgments'
about land affecting the land-use pattern, there are a number of hard-line
social attitudes towards land and its use which have also played a part. Old established examples include
* landowners have the right to use their land as they wish
* a productive (i.e. commodity-producing) land use is always better than a non-productive or consumptive use
* Australia has more than enough land for all purposes
* all land is much the same, apart from its location
* left alone, degraded land rehabilitates itself
* when resources run out, you move on.
More recent attitudes which can be widely detected include
* any extension of the area devoted to productive uses is wrong
* land development of any type, industrial or primary, should be regulated to the point where the side effects on third parties are undetectable.
Costs and prices
Turning from attitudes and perceptions to more direct economic considerations, Australian land use, especially primary production, has always been in the throes of adjusting to one or other fluctuation in export prices. Wool, meat, dairy products, and minerals all offer good examples. For example, a weighted price index over all main export commodities rose over 70% between mid-1986 and 1989; eventually it will fall 70%! Another economic consideration often associated with both early expansion of settlement and recent decline in small rural centres, has been declining transport costs.
A third economic factor controlling land use, at least as important as export prices and transport costs, has been Federal fiscal, monetary and redistribution policies. Instruments such as tariffs, subsidies, tax rebates for development works, differential interest rates etc. have the effect, usually, of altering real prices differentially for different land uses and hence of changing the balance between land uses.
Development control of private land
The main institutional factor affecting the use of privately owned land in Australia (at least since the days of the closer settlement push) is that most such land is subject to local zoning schemes which restrict (or, occasionally, encourage) the land uses the owner can practise or the ways in which s/he can practise them. These schemes are usually developed and administered by local government authorities subject to State government supervision through State planning departments.
Other State agencies impose regulatory controls on a variety of land-use and management practices. These range from pest control through air- and water-quality controls to land-clearing controls.
Public or Crown land, which comprises some 90% of the country, is largely managed in disjoint tracts by various special-purpose State resource agencies such as those with responsibility for forestry, national parks, vacant Crown land, the coastal zone and catchment areas.
In Victoria the allocation of public land between agencies is handled by the Land Conservation Council, but the other States lack comparable bodies, and allocation by interdepartmental committees is the norm.
In all States, there is an increasing requirement for public land to be managed according to the dictates of formally prepared management plans. The content of these is variable but they usually identify zones to be used for different purposes, development works to be undertaken and the policies which will guide management decisions.
The other main institutional device affecting both public and private land is the use of environmental impact assessment procedures. Under both Federal and State legislation, designated major development proposals may be required to demonstrate acceptable predicted impact on the bio-physical and, increasingly, the socioeconomic environment before being approved.
Land-use problems and prospects
In the foreword to the 1939 edition of their classic text Land utilisation in Australia, Wadham and Wood say that land utilisation is usefully viewed as a matter of balance between uses, a balance which can be tipped one way or another by technological advances, prices, attitudes, etc.
Fifty years later this is still a perceptive way to view land-use change, but a qualification is required, namely that with every year there are greater pressures to tip the land-use pattern in ever more directions even while the remaining possibilities for such changes are diminishing. Briefly, there is an increasing scarcity of land for most main categories of land use in Australia, and the causes and effects of this scarcity are at the heart of our land-use problems.
Confluence of increasing demand and falling supply
As one expression of Australia's growing national wealth, there have been increasing marketplace demands for land for both established uses and new uses (such as hobby farms). Simultaneously, there have been increasing political or non-market demands for land to be made available for consumptive uses such as recreation and conservation (Map 1.1).
Demand is one side of the scarcity equation; supply is the other. At any time there is a maximum area of reasonably suitable land which could be made available for any particular land use, i.e. made available through purchase or statutory dedication. This maximum can be increased or decreased by changes in factors such as
* transport costs
* available technology
* input and output prices
* the area of land either too developed for the use (e.g., cleared areas can no longer be used for forestry) or degraded to the point where it is no longer suitable for the use
* the area subject to performance standards or zoning restrictions on that use
* the area of public land dedicated to uses other than the use in question
* the area regarded as environmentally hazardous for the use in question.
Falling transport costs and new technologies have, until fairly recently, tended to increase the land potentially available for many uses in Australia. Now, however, this trend is probably being reversed by the loss of potentially available land for many uses through overdevelopment, degradation, backfiring technology (e.g. pesticide resistance), zoning and statutory commitment.
This confluence of increasing demand and decreasing supply has intensified market-place competition for private land and political conflict over the use of public land. This competition and conflict has been accompanied by increasing demands for the rehabilitation of degraded land, for `softer' technologies and for restrictions on the use of land for `socially unacceptable' purposes.
Community perceptions of major land-use issues
The above `scarcity' diagnosis of Australia's land-use problems emerged from an analysis of the results of a CSIRO survey in 1979 of people's perceptions of major land-use issues. About 350 people in government, business, interest groups and academia nominated what they thought would be the major land-use issues of the 1980s and 1990s.
The 2000 or so nominated issues fell into one and sometimes both of two categories. The first category could be labelled Issues concerning the location and management of such major land uses as urbanisation, agriculture, mining, recreation, forestry, parks and physical infrastructure. The second could be labelled Issues concerning the management and use to be made of critical regions and resources such as coastal lands, arid lands, alpine areas, water-resource areas, forests, minerals and soils.
The most widely shared perception among respondents was that the main metropolitan fringe areas (within a half-day's drive, say) would be the setting for conflict, competition and controversy in the 1980s and 1990s. Rising demands for accessible sites for diverse uses would be bumping against a fixed supply of land in the metropolitan environs.
One much-noted aspect was the displacement of agriculture by urban subdivisions, thus reducing the food-producing potential of the metropolitan fringe. Other contending peri-urban uses are active recreation, base minerals extraction, water catchments, hobby farms and landscape appreciation.
Agriculture came second to urbanisation as an issue generator and generally appeared as a land use under threat from subdivision and hobby farms as noted but also from uncertain markets, costs, erosion, salinity and mining. On the other hand, respondents were concerned at intensive practices used in agriculture, particularly the use of fertilisers and chemicals and factory farming. Expansion in the production of fuel crops was seen as a potential opportunity although this raised the issue of where they were to be grown.
In contrast to agriculture, mining (notably of uranium, bauxite, coal and beach sands) emerged as a strongly competitive land use with significant impacts on Aboriginal lands, farmlands, recreation and conservation areas, scenic landscapes, water catchments, forests and fisheries. The other side of the mining issue appeared as a concern for the `sterilisation' of valuable deposits in national parks, heritage areas, catchments and built-up areas.
Dipping now into the second category of issues, concern was most commonly expressed for the future of strongly demanded resources in relatively short supply. Coasts and native forests are good examples, both being extensively quoted.
Australia is a relatively unforested continent and clearing for grazing, mining and settlement and clear-felling (woodchipping) were seen as contentious activities, as was reafforestation with exotic species. Respondents saw the heart of the forests issue in the reconciliation of increasing demands for access to the forest resource---recreation, national parks, water supply and timber.
Australia has 30 000 km of coastline, but most of this is not where the people are. Residential and recreation demands are high along much of the Gladstone--Adelaide rim but spotty elsewhere. The essence of the coastal issue is seen as the impact of these demands on a resource which is essentially fragile in its scenery, landforms, waterbodies and vegetation.
Finally, straddling both the land-use and the key-resource categories, there was a set of nominations which we can conveniently tag as Maintenance of environmental quality and conservation of the resource base. Attention here was directed towards how land-using activities are to be carried out (in contrast to what and where) and the implications for air and water quality, flora and fauna, soil resources, water supplies and mineral and energy resources.
Processes frequently mentioned included erosion, mining, desertification, waste disposal, pollution and dereliction of unused lands. Practices associated with these processes included grazing in the arid zone, irrigation methods, crop rotations, recreation in off-road vehicles and open-cast/strip mining.
Many respondents, rather than identifying land-use and environmental issues directly, noted the changes in social, economic, international, technological and demographic processes which they foresaw as having land-use and environmental implications. Changing social values and perceptions of Australia considered to be especially significant were environmental awareness levels and acceptance of the search for alternative lifestyles.
The opportunity to explore alternative lifestyles was seen as flowing from a changing economy, which included higher unemployment, increasing affluence and shorter working hours. The changing structure of the Australian economy was the other economic agent identified, notably shifts from labour- to capital-intensive industries (especially mining) and from primary to secondary to tertiary industry.
Rising energy costs were seen to be significant through their impacts on, mainly, the siting of rural settlement and impacts on transport systems and land-use patterns within cities.
Internationally, our position as a sparsely populated, food-exporting, mineral- and energy-rich country was seen as having considerable implications, notably in overseas demands for access to our resources and a say in how they are to be used.
Technological change was seen as having special implications for certain activities, particularly transport and communications, but also in allowing a much more dispersed settlement pattern over the country.
Finally, demographic factors: our declining birthrate was seen as portentous for housing and services demand, but migration processes were given greater emphasis: international migration (especially from Asia), rural depopulation, inter-urban and `back to the bush' movements were all seen as significant.
Environmental issues, respondents were saying, are
the dust storms that accompany the winds of change. Issues arise when
using interests and values find themselves confronted by new, vocal and (often) financially strong demands for a share of the resources cake or a say in sweeping up the crumbs.
Alternatively, it is the amenity levels of established interests which are threatened by the intrusions of newcomers. Perhaps issues cannot be seen in tight geographic terms but what we can say is that issues are more likely to arise where population pressures are high, where scarce, accessible, versatile, fragile or particularly attractive resources are involved and around industries experiencing changing economic fortunes.
So much for diagnosis and prognosis. What about treatment? Survey respondents suggested a range of opportunities, strategies, approaches and prerequisites for community preparedness for coping with tomorrow's land-use problems. Reduced to their bare bones, these suggestions amounted to three injunctions on the Australian community:
1. to learn more about the extent and nature of our natural resources and the techniques by which they might be used and conserved
2. to develop appropriate attitudes (ethics, Values and policies) towards resources and their use
3. to develop appropriate controls, both allocation and management, over resources and their use.
National resource-management goals
My own way of starting to make sense of this plethora of issues has been to develop a statement of goals for a national land-use, natural environment and natural resources policy. These goals, (natural) resource-management goals for short, are general perceptions of what needs to be achieved if issues of most concern to the community are to be transformed or deflected from becoming crises. One never has time to consider all possible issues of course. It is both natural and efficient to concentrate on identifying what needs to be achieved in relation to those issues considered to be highly divisive or having major repercussions for good or ill, depending on how they are approached.
Goals also must `belong to someone', and I am bestowing these goals on government, because it is governments, I believe, which have the chief role to play in resolving resource-management issues, notably in establishing a level playing field for the struggle between the Market Interests team and the Public Interests team (and perhaps buying guernseys for the latter).
Government funds and resources will be used in appropriate amounts in programs to support the achieving of
Five conservation goals
1. maintenance of the productive
capability of the nation's soil resources;
2. maintenance of the supply and quality of the nation's :air and water resources;
3. maintenance of the diversity and distribution of the nation's plant and animal resources;
4. preservation of historic and prehistoric sites of national cultural significance;
5. creation of a high-quality system of national parks and other conservation reserves;
Three primary production goals
6. continued availability of the
nation's prime mineral, forestry, farmland and fishing resources for primary production;
7. implementation of socially beneficial natural resource developments;
8. maintenance of the socioeconomic and physical infrastructure necessary to ensure the continuation of industries based on natural resources;
Seven community-management goals
(management of social, urban and
9. creation of a high-quality national
transport and communications system;
10. creation of a high-quality national system for supplying water and energy;
11. provision of high-quality physical infrastructure for community services in the nation's urban settlements;
12. protection of life and property from the impact of natural hazards and hazards associated with the use of natural resources;
13. creation of a high-quality system of public recreation lands;
14. satisfaction of legitimate demands for land for Aboriginal occupation;
15. adequate investigation and evaluation of available policy and program options whenever there is significant controversy over the use of land and natural resources.
Goals are good
Goals are a good way to start any
potentially divisive analysis precisely because they are non-divisive.
Even a white racist is unlikely to reject the goal of satisfying legitimate demands for land from Aborigines---it all depends what you mean by legitimate will be hir response; and that is a correct response. It is short-sighted to dismiss goals as `motherhood' statements. Agreeing on goals at least gets the debate into the right coliseum---without backing any particular gladiator.
Goals are themselves means to meta-goals or broader goals. The meta-goal common to all of the above is to implement the right of every Australian to a place where s/he can live a long, healthy life, where daily life is a pleasant and satisfying experience.
Maintaining options and increasing richness of choice are fundamental to such goal-seeking. The nominated 15 goals identify aspects of resource management in Australia where a variety of people feel that important options are under threat or where choices could be significantly and effectively expanded. Achieving conservation goals, for example, is a step towards the goal of preserving options such as walking through a tropical rainforest today or borrowing useful genes from some desert marsupial tomorrow. Primary production goals are guidelines for creating wealth which in turn creates options for personal and community development. Community-management goals reflect both the satisfying of direct personal needs and the establishment of low-cost operating environments for resource-based enterprises.
We could continue pushing goals back further and further in the hope of finding the meaning of life! But, at some stage, goals have to be accepted as irreducible primitives whose values it is unrewarding to tease out further. Goals have done their job when they have stimulated ideas for reaching them.
Not quite. Besides being a crucible within which to develop strategic proactive plans, a set of goals has immediate practical value as a check list against which to react comprehensively to resource development and management proposals. When projects like a spaceport or a very fast train are proposed, they can and should be promptly tested to see how they will promote or frustrate each of those 15 goals. Goals not only remind us where we are going but also warn if we are taking a wrong turning.
We turn now to the first of the injunctions coming from that 1979 issues survey: the demand to get the facts, to increase our knowledge of Australia's resources and environments. Chapter 2 reviews what we know about the resources we have.
2. TAKING STOCK: THE NATURAL ASSETS OF A SMALL CONTINENT
The simplest definition of resources is that they are assets, `things you would rather have more of than less of'. One very fundamental attribute of natural (Nature-given) resources (soils, plants, animals, climates, landscapes, ecosystems etc.---there are hundreds of categories) is that they either cannot be moved (e.g. Sydney Harbour) or cannot be moved without losing their natural character (e.g. logged trees). Where natural resources occur is extremely important because this influences how they evolve, how they get used, whether they get conserved etc. So before selectively describing the country's natural assets we need a `mud map' of folk regions for giving them a general, widely known location, preferably something finer than the eight States and Territories but not as detailed as Local Government Areas (LGAs) of which there are 8--900.
Map 2.1 is adapted from Nancy and Andrew Learmonth's Regional landscapes of Australia and will do nicely. Every Australian child would benefit for life from being taught to draw such a picture. In practice, everyone eventually develops their own `mental map' of folk regions. All will differ somewhat and most will have fuzzy overlapping boundaries between regions.
Another basic property of natural resources is whether they are irreplaceable (non-renewable) stocks or self-replacing (renewable) flows. Soils, mineral deposits and natural landscapes are effectively irreplaceable once they are used up. Surface water, native plants and animals and the assimilative capacities of the atmosphere and the oceans are commonly regarded as available for continuing use provided the rate at which they are used does not exceed `threshold level'. Above threshold level, processes are set in train which markedly change the nature of the flow being delivered, e.g. the size of the fish being caught gets smaller each year.
Do we know what we have?
The question of what natural resources we have can only be answered in relation to some purpose. Land suitable for growing opium poppies is a resource if you are trying to corner the world heroin trade, otherwise not. Our less dramatic purpose is to consider Australia's prospects for reaching 15 national resource-management goals and so our attention must be on the resources singled out in the wording of those goals.
A tranquil tectonic plate
Australia began to drift away from the ancient southern continent of Gondwanaland about 125 million years ago. The Australian continent is essentially a tectonically tranquil broad platform with a long low `mountain range' along the eastern margin. It is both the lowest (average height of 330 m) and flattest of the continents; to travel hundreds of kilometres without significant change in landform is common (Map 2.2).
Because there has been little uplift of the land
surface to rejuvenate streams so that they actively erode the landscape
(streams run faster in steeper country), ancient terrains from Tertiary times
(between one and 70 million years ago) remain, though deeply leached of the
soluble minerals needed for plant growth.
Earthquakes are few (less than 1000 detectable seismic events a year),
probably because Australia (unlike New Zealand and Papua New Guinea) is sitting
safely in the middle of the Indo-Australian plate as it grinds north towards
Asia and the Pacific plate (Map 2.3).
Australia has been fortunate to have competent geomorphologists like Joe
Jennings, Jack Mabbutt, Ernst Loëffler and Brian Ruxton to trace, map and
explain the surface shape of Australia in broad terms (Map 2.4) but we still
lack detailed knowledge of land height above sea level at the scales we
need---every 100 m or so across the country. The Federal Government's Land
Information Group, AUSLIG, is working on producing a digital
elevation model, as it is called, which will eventually make such information
computer terminal. Such information is necessary, for example, for predicting frost incidence in areas where there are no meteorological stations.
A thin skin of soils
Sitting on the physiographic surface of the continent is a thin skin of soils, the most basic of all natural resources. They have been formed from bedrock by a variety of wind, water and `deep weathering' processes well summarised by Cliff Ollier.
While there are no classes of soils unique to Australia, certain soil types do occur much more commonly here than in northern hemisphere continents. This results from the long period of geological stability of the Australian continent, the small extent of recent glacial activity, the flat terrain and the dry climate. These include unconsolidated sands (about a third of the continent), saline (chloride-affected) and sodic (sodium-affected) soils, hard-setting soils, soils low in nutrients and organic matter, cracking clay soils and soils with abrupt changes in texture with depth.
We are not making a lot of progress in learning
more about what soils are where. Australia is one of the few first world
countries without a national soil-mapping agency. Pedology, the soil mapper's science, is
unfashionable and pedologists are retiring faster than they are being
trained. The main soil map of Australia
is still Keith Northcote's compilation for the Atlas of Australian Soils (1960-8).
It is drawn at a scale of 1:2 million which is enough to substantiate
in Chapter 1 that Australian soils are indeed infertile, shallow, stony and salt-prone. For example, most Australian soils can store very little water, a serious weakness where plants are so vitally dependent on soil-water reserves to carry them through from one chancy downpour to the next.
Map 2.5 interprets the Northcote map in another way. It is an experienced soil scientist's evaluation of which are the more and which are the less (potentially) productive soils across the country. Less than 10% of the country has reasonably productive soils and lots of this area lies in climatically unfavourable areas, i.e. unfavourable for agriculture. There are large areas where, in spite of deep soils and good rainfall, tree growth is poor because of nutrient deficiencies, e.g. the low scrubs of much of Cape York Peninsula (870--2100 mm rainfall) or the scrubs of the Henty peneplain in south-west Tasmania (2500 mm rainfall). Northcote and Skene estimate 5.3% of Australia to be saline and 32.9% to be both saline and sodic. Sodic soils are often highly erodible.
The amounts of phosphorus available for growing
plants are pitifully low in most Australian soils other than those developed on
younger basalts or basalt-derived alluvium.
It is not surprising that superphosphate has twice been a decisive
material in Australian agricultural history.
It was applied to wheat in the early years of the century after yields
had fallen dramatically, even in the fertile Victorian Wimmera, and was soon
used universally. Thirty years later it
was introduced as top-dressing on
pastures of European clovers and high-grade grasses, imported into southern Australia to replace the native grasses that were adapted to poverty. Adding to the problems of Australian soils, at least in arid areas, available nutrients are concentrated in the upper few centimetres and hence, if these are eroded, plant production is reduced drastically.
Map 2.6 is based on the work of a maverick Argentinian scientist named Papadakis. It shows Australia divided up into agro-climatic zones according to the range of crops which could be grown within each zone. To re-emphasise the point that the way we view resources depends on our purpose, contrast Map 2.6 with Map 2.7. While Map 2.6 is of little interest to the Australian Tourist Commission intent on identifying tourist promotion areas, Map 2.7 shows Australia divided up into human comfort zones. These summarise the amount of artificial heating and cooling required for people to stay comfortable, with all that that implies for the tourist trade. So, two climate maps, two resource sets.
We have enough regional-scale climatic knowledge, accumulated from about 1000 weather-recording stations around the country, to draw such interpretive maps although our ability to interpolate (fill in) what goes on in the gaps between stations is still somewhat limited. It will be ironic if our ability to interpolate climate between stations matures just as we enter a period of rapid climatic change when historical records cease to be a guide to what to expect.
Mean summer maximum temperatures vary from 13°C to 33°C across the continent. The highest maximum on record is 53°C at Cloncurry (western Queensland). Minimum temperatures are more important for determining limits to plant growth. Coastal areas and the wet tropics are frost free. Inland, however, sub-zero temperatures are recorded even in the tropics, especially at higher altitudes, and the severity of frosts increases towards the south, especially in the east. The lowest minimum on record is -22°C near Mt Kosciusko. We can produce reasonably accurate maps showing average number of frost-free days a year and the timing and intensity of frosts.
Jetse Kalma has recently mapped and modelled the continent's broad wind patterns for the first time. His maps help to explain why some areas, even though well inland, get high deposits of sea salt each year. They also help to explain how significant areas of soil in eastern Australia have been formed from particles of soil carried from the west on the prevailing winds over centuries. Map 2.8 shows both the average erosive power of the winds and their resultant (average) direction.
Winds in the form of cyclones are an aspect of the climate warranting extreme respect. About 13 severe tropical cyclones a year form off Australia. A zone of tropical cyclone hazard extends from Geraldton in the west to Brisbane-Gold Coast in the east. Cyclones have however been recorded as far south as Perth in the west and Coffs harbour in the east (Map 2.9). In central and northern Queensland and the Gulf of Carpentaria tropical cyclones are the major cause of flooding, whereas in New South Wales flooding is the result of an interplay between tropical pressure systems and a southern-westerly circulation which creates systems producing heavy rain. On average, about one cyclone per year crosses the coast in each 5x5° grid cell.
Rainfall and runoff
Rainfall over the continent is related mainly to latitude which correlates with the paths of low-pressure systems (Map 2.10). The northern part of the continent experiences a predominantly summer rainfall sucked in by low pressure associated with heating of the tropical part of the continent. In the south rain is largely associated with low-pressure cells striking the continent from the west in winter.
Most Australians would bet that this country
receives the lowest average precipitation over its land surface of all the
continents; the correct answer is Antarctica.
Still, one third of the continent is arid on any assessment---traditionally
meaning average rainfall of less than 250 mm a year in the south and
350--380 mm in the north. Rainfall here does not exceed evaporation in any month of the year. Extremely arid country does not support perennial vegetation; only plants with a life cycle short enough to be completed on a single fall of rain can persist there. There is no generally accepted functional (plant-growth) criterion for distinguishing arid from semi-arid country.
Another third must be regarded as semi-arid, meaning `not arid but receiving insufficient rainfall to grow rain-fed crops'. The potential evaporation rate of water at any place is determined by available solar energy and thus by latitude. Plants die by cooking if they cannot get sufficient soil-water to satisfy evaporative demands on their leaves and keep cool. Because of regional differences in potential evaporation rates (2.8 m a year in Alice Springs, 0.5 m in Tasmania), rain-fed crops require more than
*250 mm mean annual rainfall in the south
*375 mm in most of New South Wales
*500 mm in northern New South Wales and south-eastern Queensland
*625 mm in north-eastern Queensland
*750 mm in north-western Queensland, the Top End of the Northern Territory and the Kimberleys.
A substantial review of Australian water resources,
Water 2000, was published in 1983
confirming much of what was already generally known
but also adding useful detail. As well as having large areas of low rainfall, Australia's precipitation is also extremely variable from year to year by world standards. If average variability of rainfall is expressed as a percentage of mean annual rainfall, it is only the Top End and the south-east and south-west coastal rims which have less than 20% variability; most of the arid zone has greater than 30% variability and the Pilbara over 40% (Map 2.10).
Low rainfall means that many streams carry little water considering the area they drain. The Murray-Darling system, for example has about 1.5% of the runoff per unit area of China's Yangtze-Kiang River. Because Australia is the flattest continent, rivers are slow-flowing (the Darling falls at 5.6 cm---just a thumb's length---per km over its 2000 km length) and much of the continent drains inland rather than to the sea; the Lake Eyre Basin internally drains about a sixth of Australia. Long stretches of river have no tributaries; from the Queensland border to where it joins the Murray at Wentworth the Darling has no tributary worth mentioning and if it were not that the river runs in a clay channel it would probably be lost in the sands of a desert as are some rivers in central Australia.
Australian rivers deliver fairly small quantities of water and sediment to the coast but carry high loads of dissolved salts. Why? Water quality in rivers is highly dependent on water quantity; high flows come from surface runoff (rather than from groundwater) which has the dual effect of mobilising sediment (creating turbidity) and diluting salty groundwater baseflows. Groundwaters tend to be salty because they are commonly stored in marine sediments laid down in former oceans.
About 65% of all surface runoff occurs on the 21% of the land surface around the northern edge of the continent from Brisbane to the Kimberleys (the fraction of rainfall running off is closely related to total rainfall). Runoff varies markedly with season over most of Australia, the ratio of peak season flow to trough season flow commonly being hundreds of times the same value for typical European and North American rivers. The difficulty in using this northern runoff is that it occurs intermittently following high-intensity storms.
When they flood, Australia's inland rivers can rise quickly in response to intense tropical rainstorms despite their large flat catchments. At other times, especially in the lower parts of the Murray-Darling system or round Lake Eyre, impending floods can take several weeks to arrive. Inland floods disperse much more slowly (over many weeks sometimes) than those in the small steep catchments of coastal rivers. Again, flood flows in Australian rivers are a much higher multiple of average flows than are flood flows elsewhere.
Wetlands are areas of shallow standing or flowing water, salt or fresh (e.g. swamps, billabongs, shallow lakes, marshes), and are under the same broad climatic controls as rivers (Map 2.11). In northern Australian wetlands plant and animal life must cope with great changes in water supply between seasons. In response to lower and less regular rainfall, inland wetlands are smaller and even more seasonal and are often brackish in the dry season. In the arid interior, wetlands may be dry for years on end, but in the rare wet year such as 1989 lakes and swamps are abundant and full and become important habitats for waterfowl. In the better-watered south-east and Tasmania, permanent wetlands are more common, especially on floodplains and at the margins of high ground. There is also a distinctive set of wetlands in the coastal zone, where seepage from sand dunes can maintain permanent wetlands even in rather dry areas, e.g. around Perth. Along muddy coasts with a large tidal range, as in northern Australia, there are extensive tidal wetlands that usually support mangrove forests. In the southern half of the continent tidal wetlands are restricted to sheltered inlets and there are fewer mangrove species.
Nationwide distributions of wetlands of various types have been described by Kees Paijmans and others. The digital records of Paijmans' excellent study have been found after being lost for some years. In eastern Australia, 13 wetland localities have been identified as priority habitat areas for waterbirds by Wayne Braithwaite and his colleagues as result of extensive aerial surveys over a number of years.
* Lake Moondarra, the water storage for Mt Isa
* Lake Galilee, an ephemeral saline lake in central Queensland
* floodplains of Broad Sound, coastal Queensland
* North Lake Eyre
* Coolmunda Dam on the McIntyre River
* Paroo River floodplain
* Darling River floodplain
* Macquarie Marshes
* Murray River floodplains in the Murray Mallee
* Murrumbidgee--Lachlan confluence
*Interdune swamps in the lower Murray region
* East Gippsland coastal lakes and swamps.
About 80% of the almost two million migratory shorebirds that visit Australia each year occur in three main regions: the north-west coast between Broome and Port Hedland; the coast of north-eastern Arnhem Land and the Gulf of Carpentaria; and the south-eastern coasts and lakes between Eyre Peninsula and Corner Inlet, Victoria.
In Victoria, it is recognised that about a third of the State's wetlands have been lost in the last 200 years and a Wetlands Conservation Program has been established with policies covering wetland purchase, water-level maintenance, minimal further drainage and selective restoration.
Perennial lakes 9 650
Intermittent lakes 12 730
Dry and episodic lakes 120 750
Swamps 90 460
Reservoirs 6 340
The paucity of permanent surface water serves to emphasise the major role played by (under) groundwater in sustaining agriculture, mining and settlement in Australia. Groundwater occurs in near-surface aquifers (porous layers) covering about a quarter of Australia as well as in deeper sedimentary basins covering two-thirds of the continent and provides about 14% of all water used for human activities. In area terms, human activity in about 60% of the country is almost totally dependent on groundwater and elsewhere it is used to supplement surface-water supplies.
There are large untapped groundwater resources in Northern Australia and Tasmania where recharge from rainfall is at present occurring. In the low-rainfall parts of Australia groundwater is largely a fossil (non-renewable) resource, albeit a very large one. However, despite massive reserves, pressures which drive artesian water to the surface are declining in large areas, particularly in the Great Artesian Basin (covering much of inland New South Wales and Queensland) where, commonly, water has to be pumped up another half-metre each year. Increasing pumping costs are forcing graziers to substitute polythene pipes for wasteful open bore-drains as a way of distributing water to stock. One day the technology might exist to move fossil groundwater around the country in underground rivers, turning it into a renewable resource limited by recharge rates (which themselves can be artificially lifted in many situations).
Tom Chapman has calculated that the water stored in various places has an average depth across Australia as follows
water in the atmosphere 18
Surface water 5 cm
Groundwater 1524 cm
Groundwater pollution is a problem in many countries, usually caused by leaching (dissolution and through-drainage) of fertilisers or animal wastes in recharge zones. This could become a short-term problem where groundwater moves quickly through highly porous aquifers (e.g. Perth, south-east South Australia) but a long term problem only in inland basins where turnover rates are low and recharge areas are not farmed intensively.
Wattles and gums
Of the world's 411 families of flowering plants, 221 occur in Australia. Most of those that do not occur in Australia have few members and are confined to the Americas. The number of species in the continent (around 13 000) represents only 4.3% of the world's species and might be regarded as low given that Australia occupies about five per cent of the world's land surface. About 85% of vascular (stemmed) plant species found here are unique to Australia.
Ask any botanist to name the outstanding feature of the Australian flora and you will get the same answer. It is dominated by two genera, Acacia and Eucalyptus---wattles and gums to John Citizen. Both are widely distributed and both are rich in species, collectively over 1000. All are evergreen and the same leaves have to withstand both winter storms and the `sprites of flame and drouth'. Almost as characteristically Australian are the `hummock grasses' of the genera Triodia (spinifex) and Plectrachne, particularly in arid areas.
Rainforests are closed-over forests dominated by neither acacias nor eucalypts and although only occurring in small residual pockets along the east coast, across the North and in Tasmania, are extremely rich in both plant and animal species. Australian rainforests comprise only 0.2% of the world total, but this small area contains about five per cent of total global rainforest species, including the greatest concentration of primitive flowering plants in the world. Many rainforest species are likely to have descended fairly directly from those in the wet forests which covered much of Australia at the time of its separation from Antarctica 50--60 million years ago. Eucalypts and acacias represent the species which evolved from the wet-forest species to cope with the more arid and probably more seasonal climates of the last 25--30 million years.
There have been many excellent regional-scale vegetation inventories undertaken for particular purposes. The only Australia-wide map of pre-European vegetation is John Carnahan's 1976 effort for the Atlas of Australian Resources. In 1989 Carnahan also completed a map of present-day vegetation (compiled at a scale of 1:1 million). Frank Bullen and others have digitally compared the two maps, so we can begin to really see just how much of the original vegetation has been replaced in 200 years.
In 1973 the Bureau of Flora and Fauna began the
massive task of collecting, identifying and
recording all of the country's plant and animal species. Their Australian Biological Resources Study supports the ongoing publication of the Flora of Australia, the Fauna of Australia and the Zoological Catalogue of Australia. Herbarium and museum records provide patchy but still valuable information about the distribution of individual plant and animal species.
A unique fauna
The Australian fauna has been derived from three main sources: the original fauna present on the continental plate when it broke away from the supercontinent Gondwanaland in Cretaceous times (70--120 million years ago), immigrants from South America in late Cretaceous times and immigrants from south-eastern Asia which began to arrive in the Middle Tertiary era when Australia collided with Asia.
Marsupials (pouched mammals) and monotremes (see below) make up the typically Australian mammals. The other native furred animals, placental mammals, are relatively recent arrivals and, in species terms, outnumber the marsupials. From an ancestral kangaroo-like creature there developed the big Red Kangaroos that live on the inland plains and the forest-dwelling Grey Kangaroos. Heavy-footed kangaroos, the rock wallabies, also evolved, as well as a variety of small swift things that haunt tussock and undergrowth. Two kangaroos, in tropical Cape York, have climbed back into the trees and eat fruit and leaves. Wallaby, Wallaroo, Tungoo, Paddymelon, Potoroo: these are all kangaroos springing from one or perhaps two kinds of ancestors. Ancestral possums evolved into the nest-building ringtails, and bushytails and others that live in hollow trees. Some possums developed membranes down their sides. These enable the so-called `flying squirrels' to glide almost noiselessly from tree to tree. The same story of isolation, evolution and radiation through a big and varied continent can be told of other stocks---the marsupial `cats', mice and wombats and many more.
Even more archaic than the marsupials are the monotremes, found only in Australia. These, the Platypus and two species of spiny anteater, although true mammals with fur and milk glands, nevertheless lay tortoise-like eggs and retain various internal features that show their fairly close relationship to reptiles.
The `recent' arrivals include the bats, the ancestors of which were able to fly here. Then there are the true rats and mice, the forebears of which probably drifted here on floating debris. The small Asiatic wolf, the Dingo, almost certainly arrived here recently (within a few thousand years), brought by the nomadic Aborigines perhaps, and so it did not, and now probably never will, differentiate into more than one kind.
Further illustrating the high diversity and endemicity (meaning `occurring nowhere else') of the Australian fauna, we have
* about 850 species of birds, 70% of which are endemic
* about 700 species of reptiles, 88% of which are endemic.
Geographic distributions of many Australian vertebrate (back-boned) animals are still imprecisely known. Nevertheless, approximate range maps are now available for birds, mammals, reptiles and amphibians.
Australian invertebrates are largely unknown. We have about 300 000 insect species, most of which have not yet been described. For example, in a recent collection of 630 species of spiders and beetles on a 20 ha site at Wog Wog, New South Wales, 530 had not been described before.
Sea and shore
The natural resources of the Australian coastline have been documented comprehensively by Bob Galloway and others. In a massive exercise in air photo interpretation they recorded, largely in computer-readable form, geology, landform, vegetation and land use for each of 3027 10 x 3 km sections of coastal lands. Other more specialised inventory exercises have concentrated on describing the resources of estuaries (about 750) and beaches.
South of latitude 25° (Shark Bay to Fraser Island) the coast receives high energy swell from the Southern Ocean and, except for the tropical north-west, tidal ranges are low to moderate by world standards.
Australia has four main types of coastlines, the most `low-lying' of which are the tidal flat coasts laid down in areas where wave energy is low, e.g. where the continental shelf is wide. Included here are the mudflat coasts of northern, north-western and southern Australia which, among other important aspects, support a large proportion of the world's wading birds for at least part of the year. Broad intertidal zones have developed around the low-energy shores of gulfs and estuaries in northern Australia where the tidal range is large. Wide tracts of mangrove swamp are backed by saline flats which flood during exceptionally high tides.
Barrier coasts have lagoons or estuaries, often filled in, behind their beaches. These occupy most of the east coast between Melbourne and Cape York and most of the Gulf of Carpentaria and the Top End of the Northern Territory. The coastal flood plains of the east coast streams have to be regarded as the most flood-prone areas of Australia. Storm tides, by delaying runoff, commonly contribute significantly to flood height and duration.
Rocky coasts, commonly with cliffs and with some sort of shore platform, occupy big sections of Tasmania, the Great Australian Bight, the South-West and the Kimberleys; mainland beach coasts make up the `non-rocky' sections of these regions.
The Royal Australian Navy Hydrographic Service acts as the national hydrographic authority. It runs a small but active bathymetric charting program. At the Australian Oceanographic Data Centre it operates several computer-based information systems built around a combined meteorological-oceanographic database. Charting for general navigation purposes is adequate throughout the 200 mile Australian Fishing Zone. There are 150 tide gauges installed around Australia but many are antiquated. An upgraded system is vital for such tasks as measuring the Greenhouse effect on sealevel.
Estuaries and their associated tidelands and wetlands are the biologically richest ecosystems of the coastal zone. Most of the species that make up the nation's seafood catch depend on coastal estuaries and tidal marshes during some or all of their life cycle. The principal classes of coastal ecosystems focus around mangroves, seagrassbeds and kelp beds and coral reefs. Most of Australia's 12 000 sq km of mangroves occur in the tropics, as do coral reefs. The Great Barrier Reef includes around 2900 individual reefs. Sea-grass beds occur in a variety of situations around the coast and, while thought to be important primary producers in Australian marine ecosystems, they have been poorly studied. The biological resources around Australia, out to the continental shelf and beyond to the 200 nautical mile Fishing Zone are certainly not spectacular by world standards.
In 1986--87, the Australian fish catch was about
160 000 t compared with about 12 million t by Japan, the world's leading
fishing nation. However, while the
volume of the Australian fish catch is negligible by world standards, its value
is very significant because it includes high-priced species such as prawns,
lobsters, abalone and scallops. The
reason for Australia's small catch is that the largely subtropical waters adjacent
Australia are relatively poor in nutrients and thus do not support large populations of photosynthesising organisms. The nutrients in question are the same ones that farmers put on crops to enhance yields. Elsewhere in the world, such as the coasts of Africa, Peru and North America, there is large-scale upwelling. This is a process which recycles nutrients from the deep ocean waters to the surface where, in the presence of sunlight, the microscopic plants of the ocean can utilise them and produce organic compounds which are the start of the marine food chain. Upwelling can be thought of as analogous to deep ploughing the land to bring nutrients to the surface. This process occurs only in restricted areas and sporadically around the Australian coast. Under a different process, even small changes in the sea-surface temperature of the main currents flowing southwards off the east and west coasts of Australia can affect fishing catches and, interestingly, on-shore rainfall.
While our marine plants and animals show many similarities to those of nearby oceans and shores, our long diverse coastline supports a great number of species. It is the species of the southern coast which tend to be unique to Australia.
The Great Barrier Reef follows the east coast south from Torres Strait for about 2000 km. Apart from coral reefs, it contains about 250 continental islands and 300 sand cays. The outer reefs are about 50 km offshore and extensive coral zones occur between the outer reefs and the coast. The Reef's inhabitants are amazingly diverse, including about 400 species of hard and soft corals, over 1500 species of fish and thousands of species of molluscs, sponges and echinoderms.
Apart from oil and gas fields, little is known about the potential for marine minerals. On the continental shelf there is some exploration for tin and gold. By 1992 there is likely to be some exploration for phosphatic minerals on the slopes of the continental shelf and manganese, nickel, cobalt, and copper nodules and polymetallic sulphides on the abyssal plains.
Why is Australia mineral-rich?
Geologically speaking, Australia is made up of the Australian Shield occupying the western two-thirds of the continent and regions associated with the Tasman Geosyncline (trough) occupying the eastern third. The Australian Shield comprises extremely ancient rocks and is highly mineralised; it has provided the greater part of Australia's total production of gold, lead, zinc and uranium. Also, the long history and relative stability of the Shield have provided unequalled opportunities for the weathering and leaching processes which form iron ore, bauxite and nickel ores.
The building of the eastern third of the continent involved the fillng in of the Tasman Geosyncline. Regions associated with the Tasman Geosyncline are markedly different with respect to mineralisation processes and have failed to produce the major ore deposits of the Shield. They are much younger and have been subject to uplift and deposition processes, particularly in New South Wales, Victoria and Tasmania. In Queensland a relative lack of uplift activity has permitted the extensive deposition in the Great Artesian Basin which we recognise today as massive coal deposits.
Map 2.14 shows the country's 13 major mineral bearing regions, termed metalliferous provinces. Areas outside these are the 20 or so sedimentary basins which can also be mineral-rich but rather in the `organic' minerals such as oil and gas and the chemical precipitates such as limestones and phosphate rocks. The sedimentary basins extend considerable distances beyond the continental land mass in places, creating the promise of offshore oil.
Extent of mineral resources
By definition the task of mineral-resource assessment is to make a set of estimates about unknown deposits. Basically, this is done by geographic or geologic analogy (similar areas yield similar quantities of minerals) or by the judgments of expert geologists.
Assessments by the Bureau of Mineral Resources, Geology and Geophysics show Australia to be particularly well endowed with most of the important mineral resources required for sustaining a technologically advanced society. Apart from our well-known deficiency in oil, it is only chromium, beryllium, mercury and molybdenum where identified reserves are either `small' or `very small'; of these it is only mercury which is of critical importance.
The bigger the map the more you know
What we can say about our resources is
that we know, but in a fairly general way, what we have got.
The bigger the map (i.e. the larger the scale), the more information you need to complete it without leaving lots of blank spaces or using great sweeps of colour. For most of our natural resources we can probably depict much of what we know of their distributions on a map of Australia which, at most, would cover the living-room wall (a scale of around 1:2 million). We normally cannot draw resource maps at the sorts of scales needed for assisting on-site resource-management decisions without having to go out and specially acquire the required information at first hand. Such large-scale maps (1:10 000-1:50 000) exist for numerous small areas where particular management decisions have required such information to be collected at some time but these probably amount to little more than a wash of fly specks on our living room map. Several attempts, including one by my own colleagues, have been made to collate lists of these studies to assist decision-makers going into an area for the first time. The recently established National Resource Information Centre, operated jointly by the Bureau of Mineral Resourcesand the Bureau of Rural Resources, has plans to produce such compendia in detail.
Yes, but how much?
Knowing that a species or an ecosystem or other resource occurs somewhere, even knowing accurately, is only a first achievement. It does not tell us how much; log volumes in a mountain ash forest? Koala numbers on the north coast of New South Wales? megalitres of water in the Murray? etc. We have reasonable ideas on how to estimate numbers of stationary things like trees but find it expensive and difficult to estimate animal numbers, both onshore and offshore. Minerals too; great costs are incurred in going from recognising a mineral province to `proving up' the estimates of tonnages in an ore body.
Large companies, particularly mining companies, carry out exploration and inventory work where they foresee this as being profitable. But what is the role of government? Mining company submissions to a recent review of the Bureau of Mineral Resources wanted the Bureau to concentrate more on `basic mapping' of geology and resources and less on basic research into geological processes. And yet, as the history of Australian mining has shown a number of times (e.g. finding the Roxby Downs deposits), having models of geological processes can dramatically lift the payoff from exploration expenditures.
Similarly with biological resources; models of the
type at present being built in the CSIRO Division of Wildlife and Ecology can
produce reasonably reliable estimates of the presence of species, communities
and ecosystems without having to tramp every metre of the forest (Fig.
2.1). Such models run on information
provided by existing maps and by remote sensing exercises (including
interpretation of satellite imagery and air photography) calibrated from
limited ground survey. They also use
`synthetic' climate data interpolated to areas of interest from nearby
meteorological stations. Government work on resource inventory needs
to be balanced between `doing' inventories and learning how to do inventories
more efficiently. Research into
inventory-taking methods is paying high dividends in the form of improved efficiency, and the hope of researchers in this field is that governments will be perceptive enough to recognise and support this.
The starting point for learning to do better inventories is having a clear purpose. Inventory-taking is expensive and we cannot afford to pour money into data collection exercises without rigorous assessment of potential applications and links to existing data bases. That is the Iron Law of Data Collection, regularly forgotten by even experienced scientists. In the 1960s the Australian Representative Basins Program spent millions collecting data for relating rainfall to runoff, but there is very little to show for the money today.
If we had such a thing as a national strategy for natural resource inventory (and we should), it would need to be a `mixed strategy', balancing efforts at different scales---from continental to local. Not that one can ever get it right of course. Basinski's Law states that, whenever you complete an inventory exercise, someone will come along and tells you how useful it would have been if only it had been done at slightly larger scale. If you do work at larger scale, available resources ensure that you will cover a smaller area, and someone then tells you that their area of interest is just off your map!
Another basic principle for any sort of `background' inventory-taking should be to design it as though planning to describe the whole continent, even though this may never be fully implemented. A major flaw in the generally excellent work done by the CSIRO Division of Land Research in mapping the soils and vegetation of vast areas of Australia was that because each survey was `one-off' the maps they produced did not `match at the edges' when survey areas began joining up.
What is happening now is that funding bodies and agencies are reluctant to support basic inventory work. We are constantly trying to wring something more out of past inventories, but no one wants to pay to get better inventory data unless they absolutely have to---and then it gets done in an ad hoc way. For a number of ubiquitous natural resources (e.g. soils, vegetation, landform) we should be prepared, as the next step, to spend the money to produce continent-wide maps at a target scale of 1:1 million. For resources which we have spent little time investigating, we have to make a start, e.g. offshore resources and environments.
Finally, it is important that inventory data be routinely stored in computer-based geographic information systems. This way, its usefulness is enhanced many times over; data from different sources can be co-ordinated; the same raw data can be interpreted in numerous ways and the output mapped in hours rather than weeks.
Making our mark
Beyond knowing the whereabouts and quantities of current resources comes the greater challenge of knowing what they were like and what they might be like if past trends continue or if emerging forces change these trends. Again, we do not have precise knowledge by any means, but we can identify the grosser changes which have occurred since European settlement in resources which are the focus of current conservation concerns: plants, animals, soils and water bodies.
The great extermination
In 1966 Jock Marshall, an awe-inspiring one-armed zoology professor, edited The great extermination: A guide to Anglo-Australian cupidity, wickedness and waste. In it he had a group of his biologist mates document the exploitation, displacement and subsequent decline of a wide range of Australian plant and animal species and the despoliation of their environments. Not that Marshall was the first in this; he was building on earlier prophets such as Ellis Troughton, who spoke out in Furred Animals of Australia in 1941 against the indiscriminate slaughter of native wildlife.
In a chapter entitled `On the disadvantages of wearing fur', Marshall notes that in 1924 more than two million Koala skins were exported, mainly under the name of `wombat'. In South Australia, the Koala was exterminated soon after the first world war. In 1927 in Queensland, nearly 600 000 Koalas were killed in the space of a few months.
At the turn of the century, 2000 Lyrebird tails were exported in three years. In 1959, the year before exports were prohibited, about 400 000 birds were trapped in South and Western Australia alone, 100 000 surviving to be exported. And so it goes on: Bustard, Platypus, crocodile, marine turtle ...
Native plants at risk
CSIRO botanists have produced a list of about 2000 plant species (over 10% of the total flora) which they consider to be in some danger of extinction, depending on how widespread the species is and whether it is growing in areas where it is likely to be disturbed. Nine recorded species are believed to be extinct as they have not been collected in recent years (how many unrecorded?). A total of 221 species is endangered, the category of greatest risk. In Western Australia alone, 1024 species out of the State's 7000 or so native vascular plants are listed as rare or threatened; most are in the south-west in areas cleared for farming.
For example, 23 000 sq km of native grasslands once existed west of Melbourne; now they and many of their component species remain only as tiny preserves on roadsides and railway lines and in cemeteries. The New South Wales tablelands, northern and southern, yield a similar story.
We have no real idea of how common the Australian mammals were when the European settlers came. Historical records do show however that the range over which many species could once be found has diminished spectacularly. Figure 2.2 gives some examples. Australia has the worst recent record for extinctions of native mammals of any continent---18 since European settlement which represents seven per cent of our mammal fauna. It also represents two-thirds of the world's total extinctions over that period. Some 30 more species are endangered. The situation is even worse when it is realised that most of the animals that have been lost were marsupials, the pouched mammals which set Australia apart from the world.
The problem is most critical in arid and semi-arid Australia. The inland contains (or contained) two-thirds of the species that are at risk or have disappeared. One reason why the arid zone has suffered such severe losses is that in poor seasons many native animals are forced to retreat to isolated and relatively small pockets of dependable country, where they are highly vulnerable to any added disturbance.
The first such disturbances triggered by Europeans were from large mobs of sheep, cattle, horses, donkeys and goats. In harsh seasons these animals inevitably fell back to the same pockets of dependable country that the native species occupied. They changed the habitat and the native animals were progressively exterminated. Then came the rabbit which out-competed the burrowing native animals. Next came the fox and the cat, which cleaned up many remnant colonies of bandicoots, small wallabies etc. in a way which the Dingo never achieved (perhaps because it could never stray too far from drinking water).
The final straw in the sandy spinifex country seems to have been the altered fire pattern resulting from the departure of Aboriginal people from their
lands. Originally these people burnt small patches, but now the spinifex is consumed in fires that rob animals of their preferred habitats over huge areas. As a consequence of these changes, extinctions swept across inland Australia and will continue to do so. Many species are endangered and some have declined to only one or two communities. It is likely that another bout of extinctions will take place when the next extensive drought occurs.
The loss of Aboriginal `firestick farming' after 1788 has probably been an important factor in extinctions elsewhere too. When firestick farming stopped in the Sydney area, species that depended on the open parkland conditions that it maintained (such as the White-footed Rabbit-rat and Tasmanian Bettong) disappeared forever.
Among the mammals, it is the medium-sized marsupials which are most under threat---the smaller wallabies, some bandicoots, Numbats (termite eaters) and species reduced, like the Rock-wallaby, to a few remnant colonies. Recent scientific evidence shows that these meal-sized marsupials are highly vulnerable. Predation from the European Fox has been undergoing a re-evaluation and can no longer be ignored. The best evidence is from Western Australia where populations of three species living in woodland remnants in the widely cleared wheatlands continue to shrink. Numbat numbers there continued to fall until foxes were controlled. As a result, Numbats increased by 50% in 18 months. In New South Wales foxes killed an entire release of 47 rare Parma Wallabies. And so on. The adage that you can protect a species by protecting its habitat is no longer sufficient. There is no alternative to controlling foxes and cats---the introduced predators---if extinctions are to be avoided. Reserves have to be actively managed (see Chapter 5).
The bird fauna has
fared better than mammals, with only one species, the Paradise Parrot,
definitely regarded as having gone extinct.
have only been rarely sighted in recent years, e.g. the Night Parrot. Birds have the apparent advantage of mobility when times get tough, although many species never move more than a kilometre in a lifetime. For them, there is no escaping the implications of permanently reduced feeding areas or nesting sites. In southern Australia the current distribution of rare and endangered birds coincides substantially with that of the lost mammals. Ornithologist colleagues have commented that it is only a matter of time before bird species start going the same way as the mammals. One grasswren, for example, lives in the saltbush stands which are an early victim of overgrazing. Again, rabbits remove all tree seedlings from vast areas and, as sparse old trees die, the numerous bird species which depend on them must also go. Foxes are decimating the young of the ground-dwelling Mallee Fowl and there is almost no recruitment to the breeding population.
An area that carries only a few score bird species or a dozen mammals may be home to 2000 insect species. Like other animals, they are in danger of extinction when their habitats are endangered. Species particularly at risk are those completely restricted to narrowly distributed habitats:
However, there is no conclusive evidence of extinction of any mainland Australian insect as yet, and few indisputable cases of a species being seriously threatened with extinction, in spite of great reductions in range ... If we wish to conserve the characteristic insect fauna, we need a program to reserve samples of all Australian ecosystems.
Outlook for the extinction industry
One lesson of this sad chronicle is the rapidity with which an abundant species can disappear. Localised species occurring over only limited areas are in particular danger, as are species occupying specialised habitats. Today, threats to wildlife are indirect rather than direct. The basic threat is destruction of habitat. We know that the geographic range of many species is decreasing as their habitats are developed or destroyed. It is true that the massive land clearing for agriculture of the 1950s and 1960s is over. Nevertheless,
* small-scale clearing of patches of native vegetation will continue at a reduced rate in temperate Australia
* woodchipping threatens large areas of forest habitat in New South Wales and Tasmania
* there may yet be a sizeable expansion of cropping in central Queensland
* there are some significant areas which could still be opened up to pastoralism, notably in Western Australia
* chemical thinning of very large areas of Poplar Box woodlands in Queensland and northern New South Wales remains a possibility
* droughts will continue
* predators are still spreading
* most importantly, species conservation efforts are insufficient actively and significantly to throw the odds back in favour of threatened plants and animals.
Changing the rules
The returns are in. We have presided over the definite extinction of many species, the probable extinction of others and the potential extinction of many more. In two centuries we have managed to push the species extinction rate orders of magnitude above the evolutionary `norm'. We have changed the rules of the survival game in ways we do not understand. We must hope that the Great Umpire does not send us off the field.
It is a depressing story which I have no desire to harp on here. This book is about the future---where do we go now? Unfortunately, we still have not learned to do the routine monitoring (re-counting at intervals) which would take the heat out of many conservation debates, e.g. lyrebird numbers, Koala numbers.
Monitoring changes in abundance
What do we know about current trends in abundance of native species with fluctuating populations? Is any monitoring being done?
Following extensive aerial surveys, numbers of the three most abundant kangaroo species were estimated in 1981. The total of c.19 million comprised c. eight million Red Kangaroos, c. two million Western Greys and c. nine million Eastern Greys. These numbers could have decreased by about 40% in the 1982--83 drought, but no doubt numbers are breeding up rapidly following bountiful rains in 1989. These particular species appear to be in no danger of extinction, despite extensive commercial harvesting. The Greenpeace organisation, which I admire, has got this one wrong. It can in fact be argued that commercial harvesting of the abundant species helps to protect rarer species. The argument is that poisoning by farmers would replace shooting if commercial harvesting were stopped and poisoning does not discriminate between rare and abundant species. It can also be argued that creating conditions favourable for kangaroos would probably benefit other native animals. It is important that the search for more humane control methods should continue.
Broad-scale aerial surveys of waterfowl distribution and numbers (14 species of ducks and five of geese etc.) are carried out each year throughout eastern mainland Australia. The intention is to assess the effects of hunting pressure and loss of wetland habitat on waterfowl populations. Unlike coastal areas, there appears to be little loss of the inland wetlands so vital to waterfowl breeding. Despite the hunters, survey returns to date do not suggest that waterfowl are in danger of extinction.
Other baseline exercises which could be the start of monitoring programs include a recent Koala survey and the production of an all-species bird atlas by the Royal Australasian Ornithologists Union. A successful bird-banding scheme administered by the Australian National Parks and Wildlife Service might also be included here.
What can be concluded? Despite all these efforts described, our knowledge of most species is too poor to know whether population sizes and geographic ranges have stabilised within identifiable limits. Monitoring is very expensive and will remain so even though techniques are improving. Since choices have to be made, it is the recovering populations (like seals and whales) and the highly endangered species (like the Hairy-nosed Wombat) which have priority for being monitored.
The great invasion
The special vulnerability to disruption of island ecosystems is well known to biologists and Australia is the supreme example of a large, formerly isolated, island ecosystem.
At the same time as European man was clearing the land and killing the wildlife for profit, he was also, usually unwittingly, bringing in plants and animals which would in many instances turn out to be strong and, eventually, uncontrolled agents in the destruction of Australian ecosystems, including both natural and agricultural ecosystems. Compared with other places for which data is available (Britain, New Zealand, United States), exotics do not form a particularly high proportion of the total number of species of resident mammals, birds and some plant families. However, it is the competitiveness of exotics, not the total number of species, which is important.
In establishing themselves, exotic plants have been greatly assisted by the major disturbances of the landscape accompanying the expansion of settlement; stable, diverse ecosystems are harder to invade. Soil disturbance (e.g. along road verges, ploughed fire breaks) is of particular importance in the spread of exotic species. Disturbances such as agriculture, pastoralism, increased bushfires, mining, infrastructure development and urbanisation created conditions more familiar to the invaders than the locals.
In the south of the continent there are a large number of successful introductions and invaders from the Mediterranean region (e.g. skeleton weed) and, to a lesser extent, the corresponding climate zones in the western USA (e.g. mesquite) and southern Africa (e.g. bitou bush). Few of the successful plant introductions are trees---willows and poplars are the exceptions.
Some examples. Mesquite, a thorny-stemmed bush, is choking large areas of pasture around Tibooburra in western New South Wales and `has the potential to eliminate the pastoral industry from Bourke to the Victorian border' according to Doug Pearson, former Western Lands Commissioner. It is well established in Western Australia.
The prickly South American shrub Mimosa pigra has formed dense stands
across 30 000 ha of the Adelaide River floodplains. It represents a
significant conservation problem for other areas of wetland, including Kakadu National Park which now employs six people to patrol the park seeking and eradicating infestations. Annual seed production is up to 9500 seeds per sq m. While chemical control is possible at a price, biological control efforts to date have not been encouraging.
Rubber vine from Madagascar is choking out the riverine fringe communities of the Gulf of Carpentaria and the dry rainforests of north Queensland. Somewhere along the path of its westerly advance it will meet Mimosa pigra advancing east. Throw in the cane toad and you have a recipe for ecological disaster, somewhere round Arnhem Land! Stella Humphries, who has just completed a review of the subject, judges rubber vine to be Australia's worst weed of natural systems (cf. agricultural systems).
Bitou bush. Coastal dunes in eastern Australia which are under stress from human disturbance or storm erosion are vulnerable to bitou bush invasion. It is now widespread from Sydney to southern Queensland. The plant is much less invasive in undisturbed permanent vegetation. It was a recommended species for dune stabilisation for about 30 years till 1971 when the recommendation was withdrawn. While it competes very successfully with native vegetation, it is less successful than these same natives at resisting erosive forces, and dunes dominated by bitou bush are more susceptible to blowouts and hummock formation. Thus, while its ability to reduce sand drift is significant, its control is now being sought to protect native coastal plant species.
The list could be lengthy: lantana, blackberries, bracken ... Whole conferences are run on weeds, with speaker after speaker detailing hir battle with some scourge. A changing perspective at such conferences is that they nowadays consider plants which are a threat to native vegetation as well as to agricultural operations. For comfort, several of our limited number of successful forays into biological control might be recalled here
* Prickly pear, a cactus, took 260 000 sq km out of agricultural production in the 1920s in Queensland and New South Wales. It was comprehensively eaten out by Cactoblastis beetles specially imported for that purpose.
* Salvinia molesta is a free-floating South American fern which, over a period of 30 years choked large numbers of water bodies in eastern Australia. It has recently been brought under almost total control through the release of a Salvinia-relishing weevil.
Not all well-established introductions are regarded as weeds of course. Mediterranean species (e.g.subterranean clover, rye grass) have changed the face of the pastoral landscape in southern Australia, and tropical and subtropical introductions from north Africa (e.g. buffel grass) and South America (e.g. Stylosanthes species) are on the way to playing a similar role in the northern half of the continent. The point being made is not that there are `good' and `bad' introductions but that endemic plant species have been displaced from large areas of Australia since European settlement by introduced species.
In a few parts of the world Australian plants have managed to `counter-attack'. A Leptospermum is choking and drying out large parts of Florida's wetlands; a number of Australian trees and shrubs (not grasses) have successfully invaded southern Africa.
Turning to animal invaders (they have been more commonly sponsored immigrants!), every schoolboy knows it is the European rabbit which has been the most destructive of all. Spreading from the south since its introduction in about 1859, it may finally have reached its northern limit of colonisation around the Tropic of Capricorn where feed supplies during the spring to autumn breeding season become too unreliable. Apart from baring the soil to erosive forces, the great, and as yet unrealised, threat of the rabbit is in preventing tree and shrub regeneration. There may never be another generation of saltbush in massive areas of southern Australia. Because saltbush, bluebush, mulga, myall etc. are long-lived, the loss of their palatable seedlings to rabbits goes unnoticed.
Fewer people are aware of the enormous populations of feral camels, brumbies(horses), donkeys and goats which roam the drier inland of Australia, destroying the delicate, nutrient-rich surface crusts of the soils there, exposing them to erosion. Most feral livestock only seem to become serious pests to pastoralists though in certain drier seasons when they make waterholes unusable by domestic animals. Donkeys, and probably brumbies, are now being shot out (commonly for pet food) faster than they can reproduce. As populations of feral livestock are reduced, movements to conserve them (`Save the brumby'), because they are the stuff of folklore, are arising.
The installation of water bores which have allowed sheep and cattle to graze much of the semi-arid rangelands have also permitted the explosion of kangaroo and feral animal numbers. A socially acceptable way of reducing numbers of these species, assuming they are not to be `ranched' in some way, would be a technology which excluded all but domestic species from artificial watering points. First, artesian water would have to be distributed in polythene pipes instead of accessible earthen bore-drains. Second, troughs at the end of pipes would have to be designed to exclude unwanted species. Ian Burnet, a Victorian farmer, has made some interesting suggestions about how this might be done.
In the monsoonal north, buffalo `highways' have initiated saltwater intrusion into large parts of the diverse and beautiful coastal wetlands (swampy grasslands and lagoons) and this has significantly reduced numbers of many species of waterbirds there.
Pigs, foxes and cats are serious threats to native birds and mammals in wetter areas. Pigs can be enormously destructive of crops and pastures as well as being disease carriers. The role of foxes as predators on lambs is probably overrated; they function usefully in fact as predators on rabbits. They would however be a reservoir for rabies if that disease ever became established here. Cats may not so much threaten the creatures they prey on as they do the small native hunters they compete with. Marsupial native cats, for example, are now extinct throughout much of their former range.
Feral dogs (like Dingoes) kill large numbers of sheep on occasions but they are also recognised as a threat to the purity of Dingo stock through interbreeding.
Among the more chilling `animal criminals' is the cane toad (Bufo marinus). It was introduced into Queensland (by scientists) during the 1930s, supposedly to control two species of cane beetles that were damaging sugarcane crops. No adequate studies were conducted before its release to ensure that an ecological disaster would not follow, but Murphy intervened and it did. The Cane Toad is now effectively unstoppable. It is dispersing west and south out of Queensland at an alarming rate with what appear to be extremely damaging consequences for the native fauna which are its food (proper studies have not been done). Nonetheless, the Cane Toad provides an interesting example of how local fauna will eventually adapt to and check the most aggressive of invaders; several birds have already learned to turn toads over and eviscerate them, thus avoiding their highly poisonous skins.
Sheep and cattle are invaders too. As these species were introduced into the rangelands, the large kangaroos prospered, basically because of improved watering facilities, but many species of small marsupials have died out or become rare. If we want to preserve little-known species like the Rabbit-eared Bandicoot or the Desert Hare-wallaby, more national parks are needed.
Sirex wood wasp, oriental fruit fly,
spotted aphids are some of the commercially more important insect pests which
have made it to Australia. The sheep
blowfly from South Africa costs the sheep industry up to $150 million a year in
duction from its victims. The related screw-worm fly would be an even bigger disaster if it became established.
It is ironic that commercial beekeepers who have always regarded themselves as environmentally aware, and who have fought against logging and woodchipping in the forests, should now find themselves regarded by conservationists in a similarly unfavourable light. Through the very efficiency of their nectar-collecting activities, European honeybees are suspected of having a significant impact on native bird numbers and native bees and plant pollination. The research to establish the extent of such impacts has not been done though and the limited resources of the conservation movement would be more usefully directed at other targets.
Exotic pests, weeds and diseases have two main costs:
The first is the loss of, or decrease in, a rich indigenous fauna and flora in many areas. This loss is aesthetic, scientific and perhaps also spiritual, but it is not total, by any means, and was inevitable given colonisation of such a land by Europeans ... The second cost is more serious. The deliberate and accidental introduction of pests, weeds and diseases from overseas has significantly reduced the productivity of the land in many ways, but above all through a reduction in plant cover and in accelerated soil erosion.
The various approaches to weed and pest control fall into one of three main categories
* measures aimed directly at the animal or plant
* measures aimed at the animal or plant through some predator or parasite
* measures designed to operate through changes in the environment of the target species.
Direct measures usually have only a temporary effect and it follows that poisoning, trapping etc. must be cheap enough with respect to the crop or product to allow repeated use, e.g. 1080 (sodium fluoracetate) rabbit poison.
The use of predators and parasites has had some notable successes but has perhaps been overglamorised. Usually a self-adjusting balance is set up between host and enemy, resulting in only a partial reduction in the host population, e.g. myxomatosis.
The use of habitat manipulation requires ecological studies to determine and exploit potential weak points in the pest's life cycle, e.g. the establishment of vigorous pasture to crowd out weeds.
The modern concept of integrated pest management recognises the need to make use of all available approaches.
If it doesn't move ...
In 1788 forests covered less than 10% of the country and woodlands, where trees are more widely spaced and often smaller, covered 23%. Australia's total forest area has changed relatively little in recent decades. The rate of clearing has slowed radically for a variety of reasons
* planting and replanting of native forest species and plantations of exotic softwoods is increasingly common and acts to offset clearing of natural areas.
Nevertheless, clearing is continuing, though at an
historically low rate (Table 2.2). This
rate could soon rise significantly, given the rash of pulp mills
in the pipeline (up to 14) and the advent of efficient new tree-killing chemicals or arboricides (e.g. Graslan).
New pulp mills will demand large timber supplies from both private and public lands. Selling timber to pulp mills will provide farmers in high rainfall regions with a profitable way of clearing land which would otherwise remain uncleared.
Arboricides are expensive but, if the economics support it, there will be great pressure to allow their use to increase short-run carrying capacity of thousands of square kilometres of woodlands in semi-arid Queensland and New South Wales.Day of the Triffids
In large areas of the semi-arid woodlands of Queensland and elsewhere in the rangelands, regrowth of woody species after clearing, trees as well as shrubs, is a major problem for pastoralists. Woody weeds as they are known inhibit the growth of native grasses, even after good rains, and make stock mustering difficult. In the case of one of the most troublesome species, poplar box (Eucalyptus populnea), over 1000 regrowing stems per hectare is common, more than before clearing.
Accelerated erosion et cetera
sq km sq km
Rainforest 19.0 20.5
Class 1 Eucalypt forest 31.0 25.6
Class 2 Eucalypt forest 141.0 136.5
Class 3 Eucalypt forest 124.0 117.6
Tropical Eucalypt forest 65.0 65.3
Cypress pine 44.0 42.9
Public land 341.0 299.4
Private land 90.0 109.0
value for (say) forestry; degradation arrives with the subsequent unintended accelerated erosion and declining yields due to decreased water and nutrient availability. Box 2.2 lists the forms of land degradation currently recognised by the Standing Committee on Soil Conservation.
While degradation can take many forms, from weediness to the presence of pesticide residues, it is widely recognised that soil acidification in crop-pasture systems and soil erosion and salinisation of agricultural and pastoral land following devegetation of some sort (e.g. overgrazing, tree clearing) are this country's paramount land degradation problems.
Table 2.3, based on the only national survey of land degradation which has been completed (15 years old now), shows over half of our agricultural and pastoral lands in need of remedial treatment for some sort of degradation. This is, without a doubt, the most widely quoted environmental indicator ever produced in Australia. It should not be regarded as particularly accurate and it says nothing about current rates or levels of degradation, but it is a useful hook on which to hang an argument.
More recent estimates for one State are contained in a report prepared by the New South Wales Soil Conservation Service (Table 2.4)
Area in use 1 804
Area not req. treatment 987 55
Water erosion 577 32
Wind erosion 57 3
Wind plus water erosion 55 3
Vegetation degradation 92 5
(+/-water erosion) 10 <1
Irrigation area salinity 9 <1
Other 14 <1
Total area req. treatment 815 45
Area in use 3 356 -
Area not requiring treatment 1 506 45
Area affected by:
" " and little erosion 950 29
" " and some erosion 467 14
" " and subst. erosion 284 8
" " and severe erosion 148 4
+/-water erosion 1 <1
Total area needing treatment 1 850 55
Severity % State Area
affected (sq km)
sheet and rill moderate 1.81 14 510
severe 0.53 4 250
v.severe 0.31 2 520
gully moderate 5.68 45 500
severe 4.80 38 490
v.severe 0.67 5 400
extreme 0.07 570
of slopes present 2.90
Wind erosion moderate 14.06 112 700
severe 9.04 72 460
v.severe 1.57 12 550
Saline seepage moderate 0.54
Irrigation salinity moderate 0.52
Surface scalding moderate 9.18 73 570
severe 0.88 7 060
Soil acidification moderate 6.65 53 300
severe 3.38 27 120
Soil structure loss moderate 6.48 51 910
severe 10.86 87 010
Woody shrub invasion moderate 12.75 102 160
severe 4.41 35 330
My introduction to soil erosion, as a schoolboy, was Flying Fox and Drifting Sand by Francis Ratcliffe, first Chief of CSIRO's Wildlife Division. This delightful book recorded Ratcliffe's path-breaking attempts to document wind erosion in semi-arid Australia. The most substantial attempt to document soil erosion in recent years has been a survey of the extensive cropping areas of the country carried out by Graham Yapp and Frank Gibbons. In each shire they have diligently estimated the fraction of each soil type growing crops and estimated its losses.
Technologically, the most difficult aspect of the soil erosion problem is that we do not have methods for measuring erosion rates over large areas and short time periods. There have been some clever attempts to develop such methods but none have taken off. One of these is the idea of measuring the change in levels of radioactive fallout in surface soil as an indicator of loss of surface soil. Geoff Pickup uses remote sensing to track the migration of `erosion cells' across arid landscapes. The national survey being planned at present would establish a grid of reference sites across the country where soil losses could be accurately tracked through time and related to prevailing conditions. At the time of writing, the States are having difficulty in agreeing on details of this survey but it would be irresponsible if it were abandoned, as seems likely, in favour of a national land capability survey. If a major land capability survey is attempted, it should concentrate on those parts of Australia where most agricultural production takes place (the wheat-sheep zone and the Murray-Darling Basin) and on predicting the threats of erosion, compaction, salinisation and acidification to land capability in those areas.
A further technical difficulty with soil erosion studies is that it is not easy to relate soil loss to declining crop and pasture productivity. Topsoil loss and exposed subsoil lead to lower infiltration, more runoff and therefore less available water. Nutrient levels are reduced and structure (the size of soil crumbs) lost. The importance of erosion will depend on the depth and quality of topsoil and the nature of the subsoil. Often subsoil has inherently less water storage capacity and less capacity to support plant growth.
The angle of slope above which soil should not be cultivated varies with rainfall intensity, the cropping system and the soil type; some soils absorb water more readily than others. Further studies are needed to unequivocally demonstrate to farmers what rates of soil loss they can tolerate and what this means in terms of cropping frequency and cultivation practices..
Many commentators on the salinity problem in Western Australia appear
to infer that it was a wrong decision to clear for agriculture because it
caused the salt problem. I consider such
a view to be manifestly wrong. Although
two to three per cent of agricultural land has become saline as a result of
clearing, agricultural production has continued to rise. The increase in production per unit area due
to technological improvements has been more than sufficient to offset the
effects of salinity---and other forms of land degradation.
Former Director General,
Dept. of Agriculture
This is an interesting observation but it fails to recognise that the question the commentators are trying to ask is whether we would have cleared as much land for agriculture if the salinisation hazard from doing so had been recognised at the time, i.e with hindsight, was clearing excessive? While not accepting Halse's implied `no', the answer is not a clear `yes' despite the fact that dryland salinisation is a land degradation process which has removed thousands of hectares of agricultural and grazing land from productive use, not only in Western Australia but in all mainland States.
In the case of Victoria, about 6.8% of the State already contains large areas where surface soils have become severely :salt-affected and 16.2% contains smaller salt-affected patches. Plants grow poorly in salty soils, not only because of the direct effects of sodium and chloride on cell functions but because it is much harder for a plant to extract water against the osmotic pressure of salty soil-water.
The immediate costs in terms of production losses associated with dryland salinisation and the subsequent costs from the triggering of other forms of land degradation are enormous (estimated at $65 million per annum for the riverine plains of the Murray-Darling Basin alone). Since dryland salinisation problems develop slowly, it is important to make every effort to look decades ahead and try to determine the potential severity and extent of the problem. Given our present knowledge, dryland salinisation is a much greater threat to Australian agriculture than climate change.
Dryland salinisation is largely a consequence of
rises in salty water tables following the widespread destruction of native
woodlands and forests for agricultural purposes.
These deep-reaching natural pumps historically have kept water tables
down by transpiring water directly from subsoil
and weathered/jointed bedrock to the atmosphere. The cropping and pasture systems introduced following clearing cannot evaporate and transpire all rainfall entering the soil, nor can they use local groundwater to the same depth as the tree vegetation they have replaced. As water tables rise, strata previously only wetted intermittently remain saturated and where these strata contain soluble salts these will be dissolved and remain in solution. Salts are thus (re)introduced into upper soil profiles as water tables rise towards new equilibria.
Eventually, the soil surface is reached and direct seepage (groundwater discharge) to the surface initiated, especially on valley floors. Alternatively, before this happens, the root zone of the agricultural vegetation may be reached, resulting in its death and further accelerating the rate of water-table rise. There may be a corresponding increase in subsurface flow to streams and seepage to valley floors. Evaporation of surface seepage further concentrates dissolved salts and this prevents or retards the re-establishment of even salt-tolerant vegetative cover which, in turn, leaves the surface vulnerable to other land degradation processes. Generally, the more saline the encroaching local groundwater, the greater the range of susceptible vegetation, the larger the area where salinity levels are intolerable to roots and the greater the difficulty of re-establishing new vegetation. Nevertheless, salinisation processes are complex and time taken for dryland salinisation to appear following clearance of native vegetation in salinisation-prone areas is highly variable, sometimesup to 50 years.
While not such a massive hazard as erosion and salinisation, the slow acidification of soils under improved pastures in south-eastern and south-western Australia is threatening to reduce both crop and pasture productivity over large areas. The problem is really only just emerging as significant acidification can take up to 50 years to develop and many of these pastures are only 30 years old.
The problem is centred on 70 000 sq km of pastures using subterranean clover and superphosphate fertilisers. While these two form the cornerstone of southern Australian agriculture, their obvious immediate benefits have tended to mask the fact that, very slowly, they make the soil more acid. Problems of soil acidity may appear as any of several plant nutritional disorders caused by excessive or inadequate amounts of various elements. Acid soils release manganese and aluminium in quantities toxic to plants. Breeding of acid-tolerant plants is one solution which is being pursued, but application of large dressings of lime is the only practicable response at this time. Australian farmers, unlike European farmers, have not learned to accept the necessity for this expensive practice.
Superphosphate boosts soil organic matter and hence organic acids; atmospheric nitrogen fixation into ammonia by clovers releases acidifying hydrogen ions. Nitrate pollution of groundwater can be an associated problem.
In many of the older improved pastures of southern Australia scattered reports of failures of lucerne plantings, clover decline and manganese toxicity in rape provide just a hint of what will happen on a large scale unless remedial action is taken.
There are problems in Australia when it comes to managing water resources by damming rivers to allow flow rates to be matched to user needs
* water resources are not near population concentrations
* good dam sites are scarce due to flat topography and porous soils (for instance, lack of suitable dam sites threatens to limit Darwin's population to 300 000);
* even if the average flow is the same, because of the large year-to-year flow variability in Australian rivers, a dam here needs to be about 11 times larger than a dam reliably delivering the same water in the United States
* over the continent, evaporation losses from dams are generally high. As reservoir size increases, the larger the evaporation loss in relation to volume stored and there is a maximum size above which a dam cannot usefully store water.
The only advantage that the Australian environment possesses for water storage is that of a comparatively long life for dams because of the low rate of geological and man-made erosion and thus of siltation.
Not to be discouraged, we now have more than 300 large dams, including 117 on the Murray-Darling system alone. Since 1970, however, proposals for major water resource projects have been scrutinised much more closely than before. Previously dams had been seen as catalysts for regional development and as highly successful political handouts rather than as economically justified development projects. Large storage construction has slowed down, e.g. only three of the eight very large storages in New South Wales have been built since 1967. We are probably approaching the stage where only the political pressures to supply water to large urban populations will suffice to get major new dams built. The Victorian Government has just recently welched on a commitment not to draw Melbourne's water from north of the Great Dividing Range.
River management issues
Due to zealous vegetation clearing and other landscape disturbance in their catchments, most rivers in the more densely settled parts of Australia probably carry a lot more sediment today than in pre-European times. This sediment gets deposited in dams where it shortens their effective storage life or ends up silting coastal lakes and estuaries. This has two effects; it makes subsequent floods bigger and better and it reduces the biological complexity and range of habitats in riverine ecosystems. This has further consequences for fisherpersons and recreationists, among others. The common practice of desnagging rivers (removing fallen timber) to improve flow rates adds to the loss of natural fish habitat. To date no big dam has gone out of commission as a result of silting up. The Burdekin dam in north Queensland is one which is silting up rapidly.
Australia's flatness means that we have never had more than a few wild rivers suitable for such recreations as white-water canoeing. Dams and locks have subdued a number of these and others are under threat.
Eutrophication (the fertilisation of rivers and lakes by runoff from farming areas where fertilisers have been applied) is widespread, except in northern Australia. Such additional nutrients promote algal growth which in extreme cases leads to total transformation of riverine and inshore ecosystems. Coral reef systems are at particular risk because corals normally thrive only in low nutrient conditions (nutrient `deserts'). Eutrophication is hard to control because it is usually caused, unintentionally, by the actions of many people over a wide area of catchment. Changes to flow regimes associated with river regulation, particularly the reduction in moderate floods, release of cold water and rapidly fluctuating water levels have had a significant effect on native aquatic biota. For example, warmwater fish have been replaced in the lower reaches of the Murray-Darling system.
A community of living things, an ecosystem, requires 30--40 chemical elements for survival. Some of these flow into the ecosystem, pass through its plants and animals and out again as part of the carbon dioxide, nitrogen, oxygen and hydrologic cycles. The rest, including phosphorus, potassium, calcium, magnesium, iron, sodium and the so-called trace elements largely come from the weathering of the rocks of the earth's crust.
In a natural undisturbed steady state, the flow of these `crustal' nutrients into and out of the ecosystem is usually small compared with the quantities which circulate within the system. In an undisturbed forest, for example, the quantities of crustal nutrients held in leaves, litter and soil flora and fauna are much greater than the quantities coming in from weathering and leaving via soil erosion, `harvesting' etc. Destruction of an ecosystem's vegetation can lead to accelerated loss of its nutrient `building blocks' and hence to a reduced capacity to regenerate a community similar to that existing before disturbance. Trees, for example, play a role in `pumping up' nutrients leached deep into the sub-soil.
Harvesting (removing) ecosystem products, not necessarily by man, can similarly reduce regeneration potential, the impact of this loss being dependent on the soil's natural fertility, i.e. its available reserves and the rate at which `new' crustal nutrients become available for building plants and animals.
One ecosystem's loss though is another's gain. Accelerated loss from one ecosystem will boost the nutrients available elsewhere. If the receiving ecosystem is `deficient' in the bonus nutrients, it will begin to support more plants and animals and adapt to change the numbers of one species relative to another. Natural fertility sinks for lost nutrients include animal camps, termite mounds, bat camps, run-on groves in arid areas, estuarine sediments and coastal mudflats. Australia's large populations of coastal wading birds depend on nutrient concentrations built up over many years in intertidal mudflats.
Before European settlement, most parts of the continent, including the continental shelf, would have been experiencing relatively small changes in their pools of crustal nutrients available for supporting ecosystems; gains from bedrock weathering would have matched eventual losses to the ocean depths, with nutrient transfer in dust, sediment and runoff being the main pathways for this process.
One type of fertility shift which took place in geologic time has recently been recognised as being of critical importance to the survival of forest-dwelling mammals today. Wayne Braithwaite's work in east-coast forests shows that mammals are much more abundant in forests growing on fertile soils, i.e. soils developed on rocks containing high concentrations of nutrients.
Causes of significant changes since white settlement in the distribution of crustal nutrients, called fertility shifts here, include:
* accelerated wind and water erosion, particularly of nutrient rich topsoils, following destruction of native vegetation;
* more frequent high-intensity bushfires leading to nutrient transport in smoke. Whether there has been a net fertility shift from more to less fire-prone regions is not known. Fires also have other less direct effects on fertility transfer such as increasing the risk of nutrient loss through erosion;
* widespread use of chemical fertilisers on crops and pastures. Australian wheat yields declined dramatically in the late 19th century, illustrating the limited natural fertility and poor cohesiveness of most soils. Eighty years of subsequent fertilisation have failed to lift yields much above 1.5 tonnes per hectare, approximately the same as in the early years of wheat cropping. The movement of fertility from Nauru, Ocean Island and Christmas Island, our main sources of rock phosphate for fertiliser, has of course been massive. Conversely, nutrient transfers overseas in (e.g.) 1976 wheat exports (8 million t) have been calculated to include 34 400 t of elemental potassium, 24 800 t of phosphorus, 12 000 t sulphur, 8800 t of magnesium and 2400 t of calcium. Livestock exports in 1978--79 contained about 40 000 t of phosphorus which, together with phosphorus in grain exports, equalled 40% of phosphorus applied as fertiliser that year;
* greater permanent removal of plant and animal products (native and cultivated) for food and fibre for human use (including wood from pine and eucalypt plantations and native forests);
* As soils acidify under improved pasture, they
lock up some nutrients and release others in
toxic amounts; these are `on-site' fertility shifts, as are the effects of trees and earthworms in bringing subsurface nutrients to the soil surface;
* sheep camps. Sheep camps can provide useful redistributions of nutrients sometimes, by creating areas of up to 10% of a paddock where fertility loving out-of-season pasture species can flourish;
* sewage disposal. Cities like Sydney which discharge sewage at sea remove nutrients from effective circulation to a much greater extent than cities like Melbourne which use sewage to fertilise pastures. In the 1970s, about 4500 kg per day of elemental phosphorus was being discharged in Sydney's sewage, about five per cent of the amount applied annually to New South Wales crops and pastures.
* Mining moves large quantities of minerals around, but this has little effect per se on the availability of nutrients to ecosystems.
Do we understand how natural systems work?
The idea of land systems
In the 1940s, Chris Christian and Alan Stewart developed the land-system concept to help describe the vast unknown natural regions of northern Australia which CSIRO were charged with evaluating for their agricultural potential. It is an extraordinarily powerful idea, resting on the observation that even complex landscapes are built up from a relatively few types of `mosaic tiles' or `building blocks' called land units. These are repeated in characteristic patterns over large areas (perhaps hundreds of sq km) with each pattern being called a land system . Each type of land unit can be described as having a characteristic type of natural vegetation growing in a characteristic soil on a characteristic type of terrain (Fig 2.4).
Land units themselves can often be further `explained' in terms of the processes which favour particular sorts of vegetation on particular soils of a climatic region, or in terms of the processes which favour the formation of particular types of soils in particular parts of the landscape. For example, cracking clay soils impose such expansion-contraction stresses on tree roots in seasonally wet-dry climates that only grasses can survive on these soils.
The land-system idea is well illustrated by the following extract from a handbook issued by CSIRO Rangelands Research Centre at Alice Springs (now the Centre for Arid Zone Research).
To the casual observer it may appear that the semi-desert regions of central Australia are vast areas of flat to undulating landscapes vegetated with Spinifex, Mulga or Mitchell grass. However, the landscapes of central Australia are quite variable and include a tremendous range of environments. In general terms central Australia consists of a number of basin and range structures which are broad and flat. There are five main landscapes with topography, soils and vegetation strongly correlated. The cross section of typical basin and range topography shows the relationship between the units.
The five main landscapes are
1. Hills. The highest parts of the structures are hills and mountains with rocky slopes and narrow valleys. These rugged areas usually have spectacular scenery. But, more important, they are the catchment areas for water.
2. Foothills, piedmont plains and floodplains. These occur as a fringing strip adjacent to the hills and extending into the basins along watercourses. Soils vary from clays to gritty sands and are the most fertile in the region. Vegetation is open woodland or grassland.
3. Lateritic plains. Immediately below the alluvial fans is a broad band of lateritic plains with infertile red clayey soils and generally covered with mulga vegetation.
4. Spinifex sand plains and dunes. Most of the lower parts of the basins are comprised of broad sand plains and dunes with infertile deep sand soils and carrying spinifex vegetation.
5. Salt lakes. The bottoms of the lakes are dry except after heavy rain.
similar land units in the same locality. The handbook quoted above goes on to describe the strong association between the five landscapes and land use in central Australia
Pastoral pursuits (cattle predominantly) are heavily dependent on the foothills, piedmont plains and floodplains. Most of the cattle graze on these landscapes for most of the time and the majority of station homesteads are on or near them. The lateritic plains are inferior, but are important as a reserve during extended dry seasons.
Aboriginal land use is concentrated on the foothills, piedmont plains and floodplains with some use of the Spinifex sandplains and dunes. The absence of water in the latter and the pressure from cattle grazing on the former make for potential land-use conflicts.
The use of the rangelands for recreation tends to be concentrated on the rugged areas with spectacular scenery such as the MacDonnell Ranges and Ayers Rock and the Olgas. On the other hand livestock industries mainly utilise the very extensive flanking plainlands. Thus while there is scope for more integration between these two industries, they tend not to compete for the same areas and are thus complementary. There has been an upsurge in the reservation of National Parks and Flora and Fauna Reserves, some of these lands were former pastoral leases but in other instances specific environments with no former defined use have been put aside.
Land systems recognise the systematic way in which, over large regions, soils, plants and animals change as one moves from the higher to the lower parts of the landscape. Do we understand why particular types of land occupy particular parts of the landscape? It is largely the movement of rainfall runoff from ridges to drainage lines which is responsible. In semi-arid landscapes for example the movement of water from runoff areas acts to concentrate the limited resources of both water and nutrients into run-on areas. In central Australia much of the mulga country consists of a grove-intergrove pattern, with each unit consisting of a closed runoff-run-on system for falls of rain of less than about 25 mm. About 95% of both ground vegetation and trees grow in the run-on groves. Run-on groves in turn become refuges for the survival of small mammals which have difficulty in moving between widely separated refugia (unlike birds).
Before leaving land systems, consider the word land. Christian and Stewart use it in the same rich sense as Aldo Leopold.
By land is meant all the things on, over, or in the earth.
It is extremely useful to have a word which encompasses the plants, animals, rocks, soils, waterbodies etc. in an area, perceived at a human scale, i.e. with the naked eye. This is how land will be used here.
A change in the weather story
While land systems are a powerful tool for understanding the spatial distribution of our ground-based resources, we have, in the past 20 years, also made enormous progress in understanding Australia's weather---our aerial resources so to speak. In particular, we have discovered that severe droughts in Australia are frequently heralded by a huge perturbation of atmosphere and ocean known as El Nino-Southern Oscillation or ENSO.
El Nino (meaning the Christ(mas) Child) is an area of abnormally warm water that occasionally appears off Peru in late December, possibly as a result of submarine volcanic activity. This warming and subsequent cooling down are associated with a reversal every three to eight years in relative atmospheric pressure and wind directions between the western and eastern Pacific---called the Southern Oscillation. It is the switch to higher atmospheric pressures and drier air masses over the Australian region which is significantly correlated with subsequent drought conditions in Australia. The full story is more complicated and still far from understood, but drought prediction is now a very real possibility. This in turn will allow cropping plans to be modified, stock numbers to be run down in a controlled fashion, water supplies to be rationed and a host of other adaptive responses to be organised. Such optimism must be tempered by `chaos' theories which recognise that models of complex dynamic systems like weather often produce vastly different results under very small differences (errors) in inputs.
Long-term climate trends
Even if ENSO is imposing a short-term cycle on Australian weather, there are still the questions of whether we are also experiencing underlying long-term trends in or will experience sudden `permanent' shifts in such things as average rainfall, average temperature etc., either nationally or by region.
There is little evidence of persistent major climate change during the past 100 years of weather records. Despite the general acceptance of the reality of some atmospheric warming in coming decades as a result of increasing carbon dioxide levels in the atmosphere, there is no clear evidence of this translating into climate trends to date.
The problem is partly one of statistical method. Year-to-year rainfall, for example, is so variable that it is difficult to test whether a run of extreme years is the start of a trend or just an unsurprising sample---not forgetting the need to discount short-term cyclic effects before looking for long-term trends. Non-scientists do not appreciate that the decision to accept a particular `signal-to-noise ratio' as indicating that a `real' change has occurred is ultimately personal and not an `objective scientific fact'.
Are Australian ecosystems different?
An ecosystem can be broadly defined as a biotic community (community of living organisms) and its abiotic (non-living) environment. As emphasised in popular texts such as Web of Life, the reigning paradigm of ecological science is to see ecosystems in terms of `food chains' or `nutrient cycling'. Carnivores, at the top of the food chain, eat nutrients in the form of herbivores which eat nutrients in the form of plants. Plant and animal by-products and plants and animals which die uneaten are broken down by micro-organisms (the decomposers) from complex to simple nutrients which are taken up by plants to be cycled up the food chain once more.
Well, yes and no
Ecosystems differ primarily in the groups of species which play these generic roles. South African ecosystems, for example, are universally known for their veldt-grazing `charismatic mega-herbivores' such as the lordly elephant and their canine and feline carnivores. In Walden Pond it is likely to be snails and insects eating algae, slime and duckweed and being eaten by fish and crustaceans. Ignoring differences in species per se, noteworthy features of Australian ecosystems include
Termites as herbivores. Thousands of years ago Australia had large herbivores and carnivores, African-style, but these were probably hunted to extinction, and their place taken by a few smaller herbivores such as the kangaroos---and termites. Termites perform the herbivore function of eating cellulose (some also eat wood lignin), the main structural component of plant material. Several species harvest grasses and their activities directly parallel those of grazing animals. In drier parts of the pastoral zone, the liveweight of termites and their cellulose consumption may at least equal that of grazing stock. One consequence of this form of grazing is that nutrients tend to become `locked up' in termite mounds, remaining unavailable until the death of the colony and erosion of the mound. The exception is where termite colonies expand by hollowing out living trees which then benefit from being `fertilised'. In places, such hollowing out is important for creating nesting sites and refuges for birds and animals, further emphasising the key role of termites in Australian ecosystems.
Adaptation to fire and infertility. Australia appears to have provided a unique environment for the evolution of fire-adapted trees and shrubs suited to temperate climatic conditions and soils of low nutrient availability. More, in regularly removing litter, fire may be substituting for the bacterial and fungal decomposers of wetter ecosystems.
Fire is an exceedingly complex and poorly researched determinant of ecosystem behaviour. Seasonality, intensity and frequency of burns, previous fire history, relative area burned, browsing or grazing pressure and access for recolonisation of fauna from unburnt areas are all important factors influencing the post-fire history of natural systems. Some plant communities (e.g. lowland grasslands and heathlands) can lose diversity or become prone to invasion in the long-term absence of fire, whereas others (e.g. rainforest and alpine vegetation) take long periods to recover from fire.
European interference with `natural' or unregulated fire regimes can take two forms. Deliberately infrequent burning or even the attempted exclusion of fire can lead to intense wildfires and severe damage to flora, fauna and property. Conversely, a too frequent application of `prescribed' burning (i.e. prescribed according to the amount of ground litter accumulated) may cause an eventual loss of nutrients in smoke such as to reduce the more nutrient-dependent species in the community. Too short an interval between fires can also eliminate plant species whose juveniles are slow to reach a fire-resistant form.
The Australian fauna is also adapted to frequent fires. Limited experimentation suggests that wildfire does not seem to eliminate any species of bird or mammal, although abundances and relative abundances may change dramatically after fire. Intense forest fires, for example, can produce a flush of regeneration which can support large increases in animal numbers. More research is needed, however, before fire could be contemplated as a tool for routine management of Australian fauna.
Defenceless plants and animals. Most of our flora has apparently evolved with few strong defences against the weakening effects of defoliation and trampling by mammalian herbivores (e.g. by concealing their growing tips deep inside their foliage). Many have not been able to survive the arrival of cattle, sheep and rabbits; the palatable upright kangaroo grasses of Victoria's western plains are a good example. Australian trees on the other hand have developed strong defences (e.g. leaf tannins) against insect herbivores and this partly explains the success of so many Australian tree species in other countries.
Before the arrival of the Dingo thousands of years ago, Australia had few large predators (Thylacine, native cats, eagles) and many small mammals with few defences against predation were widespread---we think. We do not know just what impact the Dingo has had but we do know that the rate at which small mammal ranges are contracting has increased markedly since the arrival and spread of the European Red Fox. Just why the fox seems able to wipe out mammal colonies that survived the Dingo is not clear, but that threat is critical to the survival of mammals and ground-nesting birds already reduced to a few colonies.
Stop-go production. Over most of the country ecosystem activity is driven in stop-go fashion by irregular rainfall events. The world over, most biological activity is patchy and discontinuous at some scale and it is only the spatial extensiveness of this characteristic model (i.e. that it extends over most of a continent) which is unusual.
The predominance of low and variable rainfall means that arid and semi-arid ecosystems have evolved in such a way that each rainfall event produces a pulse of growth followed by a period during which declining soil moisture increasingly limits plant production. Around Alice Springs, for example, about 70% of single falls of rain only provide enough soil moisture to promote active plant growth for about four weeks. Rarely do follow-up falls allow this active growth to continue. Not unexpectedly, plants have developed characteristics which ensure survival through drought at the expense of those that favour high productivity.
Limits to prediction and understanding
Succession and disturbance
Ecologists have traditionally described how plant and animal communities respond to being disturbed (including being cut down, burnt, storm-damaged, diseased or, in general, being stripped of living material or biomass) as a succession in which the mixture and populations of species present changes predictably till an unchanging steady state called a climax community is reached. This traditional, unidirectional view of succession is nowadays seen as an oversimplification; communities recover from different types of disturbance in different ways.
The sorts of questions which can be posed about ecosystem recovery following a disturbance include
* What is the path of recovery after the disturbance?
* Does the system recover to its initial state, or does it change to some new state? Alternatively, how far can a system be disturbed before regulatory mechanisms break down?
* If the system shows evidence of returning to the initial state, how rapid and complete is the recovery?
While ecologists have developed a number of useful concepts (e.g. resistance to disturbance, resilience in recovering from disturbance ) and associated measures for describing the observed behaviour of disturbed ecosystems, they still have a very limited ability to predict quantitatively (numerically), in terms of species numbers, the consequences of particular disturbances for particular ecosystems. Nonetheless, experienced ecologists can often make useful qualitative predictions about the directions of change of particular species populations following commonplace disturbances. For example, while there are redundant species in most ecosystems, many have keystone species which, if removed, induce the loss of other species; the Cassowary is a seed disperser for large-fruited rainforest trees, probably the only disperser for some species.
One particularly difficult aspect of such predictions is whether or not species lost from a particular occurrence of a type of ecosystem will be replaced by recolonisation from other nearby occurrences of similar systems; predicting colonisation by `new' species is similarly difficult in the absence of empirical evidence. Australian ecosystems are especially difficult to study because of the massive and extensive disturbances they have experienced and the rates at which they are still changing in response to those disturbances.
Ecosystems as islands
For most organisms, their world consists
of habitable `islands' scattered in a vast inhospitable `sea'. Sometimes the islands are real like
Australia's many offshore islands, which are refuges for a number of species and subspecies. Sometimes there is just one habitable island
like the mountain ranges of central Australia in a metaphorical sea of deserts;
or indeed island-Australia itself.
Sometimes there are a few habitable outcrops like the alpine islands of
the high country protruding above the snowline.
For some species their habitable islands are in fact `archipelagos' of
wetlands in a dry sea, appearing and disappearing, shrinking and
growing with the seasons. Disturbance, too, (e.g. by fire, by ploughing) will sometimes push an island up out of the sea ; it is disturbed landscapes which are most vulnerable (receptive) to successful invasions (expansions).
The `fortunate' species are the ones occupying islands large enough normally to support viable (self-sustaining) populations but also within dispersal range of other islands from which recolonisation can occur should catastrophe strike. Possibilities for successful inter-island colonisation depend on a species' mobility/dispersal strategies (e.g. winds versus ocean currents; flying or swimming versus floating) and the extent and inhospitability of the intervening sea. Barriers can be as diverse as mountain ranges (e.g. for small birds), temperature zones (e.g. Mountain Pygmy Possum) or prevailing winds (e.g. screw-worm fly).
While Australia has a wide diversity of biogeographical environments, many of them are relatively small and isolated and many species can find their habitable islands only within one or two of these regions. One of the significant hazards of predicted climatic change for such species is that their small isolated islands will disappear without other habitable islands springing up within colonising distance.
To a limited extent we can identify, in terms of climate, vegetation etc. what type of landscape qualifies as habitable, actually or potentially, for a species. This is not quite the same thing as knowing the geographic distribution of that species.
Ecological islands tend to both lose and gain species under disturbance. The equilibrium theory of island biogeography states that the number of species on an island tends towards an equilibrium because of a balance between immigration and extinction rates. This equilibrium is determined in part by the size and position of the island. Small islands should have fewer species than larger islands because they have smaller populations that are more likely to become extinct. Isolated islands should have fewer species than islands close to a source of colonists because their remoteness makes them difficult to colonise. Ultimately, what happens on any one island depends on the mosaic of disturbances and responses on surrounding islands. The theory might be better named the equilibrium theory of archipelago biogeography. The equilibrium is dynamic in the sense that some species are regularly becoming extinct and being replaced by others.
The continuing need for monitoring
We have learnt many of the principles governing the workings of the natural world. There is commonly someone around who can `explain' why things are the way they are, how they got that way, and what might or might not happen to that system in the future. Much of that knowledge can be usefully expressed as rules of thumb, a form in which it can be passed from experts to apprentices. For example:
* If the predator on a generalised (unfussy) herbivore is removed, the herbivore's numbers will expand and extinguish all but the toughest plants, the numbers of which then limit herbivore numbers.
* The post-disturbance rate of recovery of species populations will be greatest for species which exhibit rapid individual growth rates, high dispersal capacities and large reproductive efforts.
* Species-poor environments fall into three general
(i) `new' environments, in which the number of species is in the process of increasing
(ii) `severe' environments, which may lose all species with relatively slight environmental change
(iii) `unpredictable' environments, in which the variability of environmental properties around their mean values is relatively high and unpredictable, both spatially and over time.
* The main result of using natural ecosystems for primary production (harvesting) is to reduce their species diversity (roughly, total number of species).
Commonly, such rules of thumb allow us to give a qualitative account of how the relationships between the `main' species operate (who eats whom, when and where) and the basic survival strategies of individual species. They can help with practical tasks such as identifying `fragile' ecosystems. Cold-country ecosystems are fragile because slow-growing vegetation takes so long to recover from disturbance. Arid ecosystems are fragile because they have very limited nutrient reserves to draw on.
Equally commonly, rules of thumb let you down. Why?
It is because of the so-called counter
intuitive behaviour of many natural systems, a phrase made popular by the
Massachussetts Institute of Technology
modelling group behind the
controversial Limits to Growth study of the 1960s. Natural systems are very complex (i.e. one change sets off cascades of consequences) and situations which intuitively appear the same according to some rule of thumb may be actually quite different in terms of the numerous feedback loops which regulate most such systems (in feedback loops a change in the amount of output from a process leads to a change in the amount of input).
Complexity aside, when all the rules of thumb have been counted, there still remain numerous starkly gaping holes in our scientific knowledge of particular ecosystems. For example, many flowering plants, perhaps several thousands, have not even been described and named; the roles played by invertebrate species (spiders, beetles etc.) and micro-organisms in ecosystem functioning are poorly documented and understood.
Our knowledge of the future is increasing each year in the sense that we are less commonly `surprised' by what happens. We are making comparatively little progress though in predicting what will happen as distinct from being able to list all the things that might happen. Partly this is because so much of what happens in the natural world is driven by events which, at best, we only understand probabilistically, e.g. that there is a 50% chance in western Victoria that the autumn rains will come before April. However, even assuming foresight about such important `random' events, we only occasionally have the knowledge to pick confidently which scenario will eventuate, e.g. just how much topsoil will be lost from this paddock if it rains x mm?
It is this limited ability to predict in quantitative non-probabilistic terms which makes monitoring of resources and environments so important. Monitoring is a substitute for having enough understanding to model trends. If it is important and if you cannot predict it then you have to keep measuring it! By regularly measuring how the important dimensions of a system have changed you can detect how close it is to approaching a threshold state, i.e. an estimated limit or boundary value where the ability of the system to perform the functions required of it is in jeopardy.
This situation is no different from the way we have to manage socioeconomic systems. If unemployment gets too high as measured (monitored), some countervailing action such as reducing interest rates is taken even though the effects of such action cannot be accurately predicted. It is monitoring which then tells us if the countervailing action has worked or needs further adjustment.
3. GAZING OUT TO SEA: THE INTERNATIONAL ENVIRONMENT
Living in a community of nations presents Australia with opportunities, problems and responsibilities. Many of these are resource-based in the sense that if Australia's, or any other country's, natural resources were to change or be used differently, our opportunities etc. would also change.
Are our resources special in a world context?
Special in what way? I am thinking more generally than the economic concepts of comparative or absolute or competitive advantage. Every country has unique resources but there are aspects of our resource complement which especially attract the interest of foreigners of various persuasions---investors, tourists and travellers, immigrants, scientists etc. Clearly, recognising the scope and origins of such interest is a necessary preliminary to deciding whether or not we wish to take advantage of that interest in any way.
Australian landscapes raise powerful emotions in many of us but with one possible exception there is no reason to think any more powerful than any other native land. The exception is that modern Australia has produced a group of extraordinary painters who have `crystallised the mute stirrings of our responses to the land'. Had anybody ever seen a country town before Russell Drysdale painted pictures like `Sofala'? Now it is hard to see one any other way. Every time you take a trip to the back country, you see Drysdales all over the place!
For tourists, it is the colours of Australian landscapes which are of central appeal---red foregrounds and blue backgrounds
Although distant mountains are blue, in fine weather, in many other
parts of the world ... Australia displays some of the richest blue and violet
shades ever seen. Whether it is the
distant MacDonnells in Namitjira's watercolours, or the steep slopes of New
England, or the Blue Mountains, or the distant view south from Kosciusko, the
more lasting impression is one of colour even more than of form. The best viewing sites, seasons and hours of
the day should be noted and made known for each notable landscape. Just as there used to be `colour clocks' and
calendars' in the old-fashioned gardens of England, there should be available similar observations and knowledge to Australians and tourists in Australia.
One semiotic puzzle is the difference between interpretation As Daniel Thomas has noted, most visual interpretations of the landscape see it as benign.s of the Australian landscape by visual and verbal artists. This contrasts with the death, destruction and despair which is so much the focus of our early romantic poetry as collected in books like Austral Garden of Verse (Hold hard, Ned. Lay me down in the shade once more ...).
The majority of course do not respond passionately to their ugly-beautiful land. The truth is, as Aboriginal lawyer Pat O'Shane has said, (white) Australians are frightened of the place. Park planners have told me that an axiom they follow in designing walking tracks is that average Australians will not venture more than 600 m from their cars. I have certainly felt scared on occasions when lost or `temporarily out of position' in the bush; I have felt apprehension on first encountering a new type of bush---like the towering, enclosing monsoonal tallgrass of the Top End or the dark mosquito-ridden depths of mature Brigalow.
Marsupials are definitely special
Australian `beasts' have evolved unique strategies for coping with life's basic problems such as reproducing, eating and getting around. For example, recent work on kangaroos shows just how extraordinary their hopping is; as the kangaroo lands it stores energy in its leg muscles which is then released to aid the next spring. Also, its guts are loosely attached inside and as these flop up and down with each hop they drive air in and out of the lungs semi-automatically!
It is the wonderment factor which brings tourists to see our wildlife, but apart from an occasional `bird spotter' tour, we have done little to capture tourists who want more than `bus window' exposure to this richness. Another reason why our natural resources are so interesting to the tourist trade is that they are still relatively natural; that is a significant part of their appeal.
Partly because the immature young of marsupials can be studied `in the pouch' they provide unmatched opportunities to understand many basic physiological processes. Australian scientists have seized the opportunity and continue to make significant contributions to mammalian physiology with all that this implies for medical science.
Even in the lower orders, Australians are special. We have ant populations of great diversity and antiquity for instance. Perhaps the Australian Tourist Commission could look into the possibilities for `ant spotter' tours?
A share of the World's heritage
The World Heritage Convention of UNESCO came into force in 1975, with the aim of ensuring international co-operation for the protection of outstanding natural and cultural components of the heritage of humanity. Each signatory country, of which Australia is one, is required to do everything possible to ensure the permanent protection of its World Heritage areas. Criteria for assessing whether a nominated area will be listed include uniqueness, evolutionary significance and cultural or natural value. Australia has seven areas on the World Heritage List including, most recently, the Subtropical and Temperate Rainforests of Eastern Australia in northern New South Wales and the rainforests of north Queensland. The others are
* Kakadu national park, a spectacular, biologically rich and (Aboriginal) culturally significant subregion;
* Willandra Lakes Region, an area of significance for charting landscape change and containing Aboriginal cultural remains up to 40 000 years old;
* Great Barrier Reef, the largest collection of coral reefs in the world;
* Lord Howe Island Group, which contains an assemblage of plant and animal species not found elsewhere;
* Western Tasmania National Parks, which contain temperate rainforest, big and old trees and wild rivers.
There are a number of other areas which could almost certainly qualify for inclusion on the World Heritage List but future nominations will probably have to be initiated by State governments. The Commonwealth has found the political flak from pushing a nomination through in the face of State government reluctance to be unbearable. Potential nominations suggested by Penny Figgis and Geoff Mosley of the Australian Conservation Foundation include
* Shark Bay in Western Australia (since backed by the Federal Government);
* Nullarbor Plain;
* Central arid zone;
* The Great Sandy Region of Cooloola and Fraser Island;
* Cape York Peninsula;
* Eastern arid region covering Lake Eyre and the Simpson desert;
*South-west Western Australia;
* Australian Alps;
* Sub-Antarctic islands (since backed by the Federal Government);
* Christmas Island and Rowley shoals;
* Houtman Abrolhos Islands.
The Figgis-Mosley book with descriptions and photographs of these areas is almost too painful to look at when you realise that you will probably never see most of them. Australia is a truly wonder-filled place.
The idea of placing areas on a World Heritage List is a bit like awarding medals in wars---most of the heroes do not get one. The world is full of places which should be preserved for coming generations. Nevertheless, `the medium is the message' and the mere existence of a World Heritage List draws attention to some of the `jewels in Earth's crown'. On the one hand listing probably protects an area from flagrant destruction; on the other, the increase in visitors which listing brings is likely to accelerate natural deterioration. On balance, a sensible strategy would be to get as many Australian places listed as possible, after confirming by proper procedures that controlled tourism, conservation and the provision of `environmental services' were to be that place's primary functions.
Also of world significance are the 12 or 13 Australian national parks which have been nominated as Biosphere Reserves. As planned under the UNESCO-sponsored Man and the Biosphere program, this system of reserves is intended to represent relatively undisturbed samples of ecosystems in the full range of bioclimatic regions to be found on each continent. We have 18 or so bioclimatic regions as mapped at global scale and the six or so unrepresented regions are predominantly in Queensland. Each unrepresented region already contains at least one large national park and it would be undemanding to complete the Australian complement of biosphere reserves.
Rare minerals, abundant minerals
The development of advanced materials is a major frontier of so-called sunrise technology which the Australian government identified as a key research area, somewhat belatedly, in 1985. The list includes ceramics (e.g. for engine blocks, high-temperature superconductors), plastics, new alloys, composites (e.g. for airframes), semiconductors, optical fibres, biomaterials (e.g. for body parts). What is relevant from a resources perspective is that Australia has major reserves of many of the scarce minerals which are inputs for producing these new materials, e.g. 30% of the world's known deposits of zircon, eight per cent of the world's titanium, large reserves (i.e in the top five countries) of tungsten, cadmium, tantalum, bismuth and manganese and 50% of the world's yttrium (emerging as a key to producing high-temperature superconductors). As well as the possibilities for exporting, having reserves of rare minerals would appear to confer an absolute advantage for undertaking their subsequent processing and fabrication.
Australia yields a wide variety of gemstones including 70--80% of the world's sapphires and most of the high-quality opal. The latter can be stunningly beautiful and rightly constitutes a major export via tourist purchases. Through the Ashton venture in the Kimberleys, we are now a significant member of the world diamond cartel.
At the other extreme (although for somewhat related geological reasons) we have mountains of iron ore, reserves of world ranking. These are being exported as fast as Lang Hancock and others can manage.
Cheap agricultural land
The Australian cotton industry is still
powerfully influenced by American-born growers who migrated to northern New
South Wales in the 1960s to take advantage of the cheap land and irrigation
water there. There has always been a
strong British and American influence on the northern beef industry and just
recently there has been concern over the extent of Japanese investment in the
better-watered beef areas of eastern Australia.
There does seem to be a widespread perception around the world that
Australian agricultural land of all types is under-valued, which is a little
strange given the unspectacular rates of return on farm capital regularly
reported by the Bureau of Agricultural and Resource Economics.
Some major overseas-financed farming ventures (including Lakefield Downs, Tipperary and Coastal Plains) have been predicated on importing superior management and adequate capital to achieve economies of scale and have foundered on technological arrogance and harsh seasons. As the original Anglo-Celtic settlers found, you need experience and luck to make a pile farming in Australia.
What is true is that we have a comparative advantage in farmed land---over three ha of tilled land per person in Australia, perhaps 10 times the average for the rest of the world. More, this figure has been growing, at least till recently, whereas in many of the older developed countries it has been declining with population growth and urban expansion.
Diverse living environments
Australia extends through 33 degrees of latitude and has almost the full range of habitats found in the whole of the rest of the world. The range of living environments, work environments, play environments available to Australians and their visitors is as varied and accessible as anywhere, although a little short on snowfields perhaps. My gratuitous contribution to the tourist industry is the idea of `high-diversity' tours: coral reefs, rainforests, deserts, high country, wilderness and wild rivers---all in 10 days.
The image of Australia which seems to appeal overseas is one of outdoor living and beach-oriented recreation. Our tourist promotions naturally de-emphasise stingers, crocodiles, sharks, sea snakes, mosquitoes, bush flies, sand flies and skin cancer. The oppressive northern `wet' season has been given a marketing facelift and become the `green' season. Ha Ha.
Some of the things which have traditionally been regarded as drawbacks to life in Australia are emerging as tourist assets in an overcrowded world---empty space, isolation, deserts, wilderness.
Takeaway flora and fauna
Trees for chipping, trees for growing
Despite our limited forest resources, we seem very willing to make our eucalypt forests available for woodchipping at bargain-basement prices to Japanese interests. The reason for allowing this is usually given as jobs and job protection. More sustainably, Australian eucalypts, sheoaks and acacias are now valued and grown in over 70 countries for firewood, shelter and timber. By further research into matching species to environments (we have over 500 Eucalyptus species) it should be possible to expand this achievement, particularly in the Third World where eucalypts have been very successful in protecting soil and helping to support burgeoning populations in various ways.
Wildflowers and other plants
Australians have been slow to take commercial advantage of their native flora. There are undoubtedly major world markets for Australian native plants, both as cut flowers and in pots. Australia has over 600 species of orchids alone for instance. The annual wildflower displays of the Perth and Kosciusko regions are sufficiently colourful to attract tourists in large numbers. The downside is that of the commercially exploited species (banksias, boronias, kangaroo paws, ferns etc.), 34 have a very restricted distribution and 12 of these are considered endangered or vulnerable. Tea-tree oil, extracted from the leaves of Melaleuca alternifolia, contains a natural antibiotic and is low in skin irritants, making it a powerful agent for helping to heal wounds. Demand is strong and M. alternifolia plantations are being established as an alternative to harvesting natural stands. To maintain a commercial edge, breeding and selection for oil content will be necessary.
Breeding to the point where plant-variety rights have been granted has recently created the possibility that Australia might at last reap commercial benefit from Macadamia nuts, the one tree crop she has given the world. Up till now, Macadamias have earned far more for Hawaii than for Australia.
Songless bright birds
I do not like birds in cages, and that includes chooks. Still there are rich markets overseas for many Australian birds: parrots, cockatoos, galahs, budgerigars; in fact, probably most of our 600 or so native species. Why cannot some of the common, even pest, species such as corellas be `harvested' and sold? It would have to be remembered that current prices are `blackmarket' prices and would drop with unrestricted exports.
The unknown sea
Establishment in 1979 of the 200 nautical mile Australian Fishing Zone under the Law of the Sea Convention brought 8.9 million sq km of ocean under Australian control, the third largest fishing zone in the world (and that does not include any claim we might make with respect to waters off the `Australian ' sector of Antarctica). This is a large fraction of the world's oceans. While we are slowly learning about the resources and natural processes of the continental shelf, we know very little about much of this area. In the meantime its main interest to the world is its fish stocks.
Gaps in the Australian resource base
Offered three wishes to significantly change Australia's resource base, would we be inclined to accept? If Australia had been endowed with better soils and more reliable rainfall, it would almost certainly have been more heavily populated in 1788 and we might now be as overpopulated as (say) Africa. The same feature can be a problem or an opportunity depending on how you look at it and at the social and technological context. One can readily imagine a `problems' scenario rather than a `progress' scenario associated with almost any suggested `improvement ' in our resource base.
What if we were less isolated for example? Being largely surrounded by oceans is nowadays a significant strategic and environmental asset. Even French nuclear testing in the Pacific offers no direct threat to the Australian environment at the present time.
What if we had a history of fighting off invaders? We might nowadays better appreciate what we have (assuming we won) and be prepared to work harder to nurture and protect it. For every gain there is a loss, and for every loss there is a gain. One generation's problems become the next generation's opportunities; the dead heart yields mineral wealth; trace elements open up the Esperance sand plains; the Birdsville track becomes a desirable tourist destination; climatic change wipes out the western wheat belt but creates a `sorghum belt' in north-central Queensland. On balance it would probably be safer to knock back the genie's three wishes.
Playing a part
There are many ways in which Australian resources and resource-using experience become available to foreign countries, companies and people. At the most obvious level we export minerals and agricultural products; we host tourists; we provide foreign aid in several forms including supplying experts in various resource-using technologies, notably dry-land agriculture and engineering.
There are other more subtle examples. As noted, eucalypts are now important trees for timber and fuel in many countries and since practically all of the hundreds of species are endemic (unique) to Australia, we provide seed to the world and have a clear duty to maintain the Eucalyptus gene pool for breeding improved varieties where they are needed.
To what extent do our resource exports hurt others? Our coal produces about two per cent of the world's carbon dioxide emissions (but less than its share of acid rain); our uranium ends up God knows where. Our mineral and agricultural exports are not highly subsidised by world standards but nonetheless probably take markets which would otherwise be supplied, in smaller quantities and at higher prices, by Third World countries. Sugar is the obvious example. By the same token, Australian grain exports keep lots of people alive and one seldom-heard `moral' argument for holding the Australian population constant is that this will allow us to remain a major exporter of food to a hungry world.
Pressures to do this and that
As the world gets hopelessly overcrowded in the next century, will we come under irresistible pressure to allow mass migration into our perceived empty spaces? The Northern Territory is the interface between Australia and south-east Asia. While not advocating frenetic efforts to `develop the North' to demonstrate that there is no room for others, I think it is important that Darwin be encouraged to become a great Australian city, reflecting the best of our culture and our commitment to this part of the continent.
Will we come under pressure to supply uranium for electricity generation? Will we come under pressure to reduce our rate of resource consumption? We are in the 26% of the world which consumes 80% of all resources flowing through the world's economic system.
And then there is commercial pressure. Are we going to be in the clutches of transnational companies keen to impose resource-management regimes which are not in the interests of ordinary Australians? The economist Ted Wheelwright has led the voices pointing out that Australia's mining sector is under a higher degree of foreign control than that of any advanced capitalist country and the significance of this for such economic management matters as exchange rates, balance of payments, capital transfers and tax avoidance.
The world political regime which will have to evolve if large transnationals are to be controlled may well be the force majeure which determines just how our resources will be used to help a troubled world. If we do not want to be forced to manage our resources under international guidance, we must, of our own volition, begin demonstrating that we are going to do our share to help the world through what looks like being a difficult century.
Transferring skills and recipes
Should we divert more of our resource-management expertise from being used in Australia to being used abroad? For example, the impact of sea-level rise next century in Australia will be negligible compared to its impact in the South Pacific and in Bangladesh. Recently Australia has offered to monitor sea-level change in the South Pacific (we cannot even monitor it properly here!). Should we be sending planners and engineers to such places to help prepare? Such action is self-interested as well as altruistic.
When work on our own problems yields results of use elsewhere, how much effort should we put into technology transfer? Current research into how to grow crops and pastures on the difficult red and yellow earths of the monsoonal north has potential application to a large part of sub-Saharan Africa, north-east Brazil and parts of Kenya and India.
A research contribution
The perspective of modern science is that we live on a small planet with limited resources. Nowadays many scientific studies of the environment must necessarily be based on an international, global view. To study the pollution caused by acid rain, the effects on the atmosphere caused by burning fossil fuels, the destruction of ozone in the upper atmosphere, the radioactive and particulate fallout produced by atomic explosions, the conservation of species and other problems, it is essential to consider the planet as a whole and to learn how to analyse global problems quantitatively. As the most politically stable, affluent and developed nation in the southern hemisphere, Australia has an obligation to contribute a southern perspective on global environmental problems. Australia has good scientists who, provided they are funded, can make worthwhile contributions to such international efforts. But science must not become a substitute for action.
Less panoramically, we also have an obligation to put some of our miserly aid funds into developing practical everyday technologies (stoves, wells, farm implements etc.) for less developed countries. While this can go badly wrong (inappropriate technology), producing more output from fixed inputs is the only hope for improved living standards which many countries have until they get their populations stabilised. Similarly, commendable moves are in train to ensure that all Australian aid is `environmentally sound', e.g. by formally assessing the environmental risks of programs.
We have an obligation (call it enlightened self-interest) not to become `free riders' on a wide range of resource overexploitation and global sink problems including
* pollution of the world's oceans (sewage, oil, garbage, toxic wastes ... );
* Greenhouse gas emissions;
* sulphur dioxide emissions;
* space junk;
* overfishing (we did do our bit for whales).
A free rider
is one who thinks that hir activities contribute very little to the problem
and, besides, where's the policeman? In
public fora the free rider pays lip service to the idea of global co-operation
to solve such problems. It is true that
we are a small
country and even though we have high energy use per head we contribute little in percentage terms to these problems. Similarly, our isolation means that they impact relatively lightly on us. All the more reason to self-regulate our behaviour. If the moral argument does not appeal, think of it as a low-cost/high-return boost for our international image!
International treaties and conventions
Treaties which we have signed and which have direct relevance for resource management in Australia, quite apart from helping with resource management elsewhere, include:
* Convention on international trade in endangered species of wild fauna and flora. Signatories stipulate that government permits are required for all trade in listed endangered or vulnerable species. The aim is to reduce international illegal traffic in wildlife.
* Convention for the protection of the world cultural and natural heritage (the World Heritage convention).
* Convention on the law of the sea. The 1982 Law of the Sea Convention is a remarkable effort by about 160 countries to establish an overall framework for managing the world's oceans and their resources. While extending Australia's `claim on resources' zone to 200 nautical miles, the convention obliges us to fish the area or licence others to do so up to a declared capacity set by Australia. The convention, for example, provides the `muscle' to ban the use of drift nets in the zone, nets up to 50 km long which snare all sorts of non-target species.
* Australia--Japan and Australia--China migratory birds treaties. These are basically conventions for the protection of about 90 species of birds which migrate between these countries and Australia, particularly including waders (such as the Japanese Snipe) and seabirds.
* Ramsar convention on wetlands. Thirty-nine wetlands with a total area of 44 549 sq km have been designated by Australia for inclusion on the List of wetlands of international importance especially as waterfowl habitat.
* Biosphere reserves. UNESCO has promoted the establishment of securely managed examples of `representative and outstanding natural and semi-natural areas of global significance', one for each major biogeographical region. As noted, Australia nominated 11 national parks as biosphere reserves.
* International convention for the regulation of whaling. Australia has played a leading role in attempts to reduce whale catches to sustainable levels.
The meeting of international treaty obligations is an area where the Federal Government can legitimately be active in natural resource management. Though signing international treaties as a back door into increasing the scope of Federal participation in natural resource management seems a policy of despair.
A bit of an empire
Australia makes claims of varying validity on an awful lot of the world (Map 3.1):
* one old continent plus its 200 mile fishing zone;
* forty per cent of Antarctica (plus a fishing zone?);
* a number of island Territories including their fishing zones (Macquarie Island, Heard and MacDonald Islands, Cocos Keeling Islands, Christmas Island, Coral Sea Island Territories, Ashmore-Cartier Reef).
Even in winter, the sun only sets for a few hours a day on this empire. What are we going to do with it? We are certainly not going to defend it with guns.
Consider Antarctica. The ice-free parts amount to only a few per cent of the continent, but these areas tend to be extremely important for wildlife. Penguins, petrels and seals use the small amount of ice-free land and the near-shore fast ice for breeding and resting while relying on the ocean for food. Biological processes such as plant growth operate slowly, intermittently and on small scales; they can be easily disrupted and they recover slowly. Antarctic ecosystems have to be classed as extremely vulnerable to disturbance.
These ice-free areas are where tourist operators want to set up shop and where mining would be somewhat more feasible. But we need to know much more about Antarctic animals and their environments before being able to predict the effects of mining or tourism on their survival. Let the point be repeated in case it did not register. We need to know much more about these animals and their environments before being able to predict the effects of mining or tourism on their survival.
To date there is little evidence of fabulous mineral wealth. At this stage, a dollar spent prospecting in Australia looks like earning much more than a dollar spent in Antarctica (the Bruce Davidson argument all over again). Unfortunately, several countries are raising the possibility of state-subsidised mineral exploration.
Australia has now decided not to sign the Convention on the regulation of Antarctic mineral resource activity. Phillip Law, founder of the Australian bases at Mawson, Casey and Davis, and a thoughtful man, says development of Antarctica is inevitable, indeed necessary, but will not significantly affect environmental values if tightly controlled; we should therefore help design those controls. Paul Keating says such a convention would be like a starter's gun for miners and I am inclined to agree. We will have to be prepared to throw every trick in the International Law book at anyone who tries prospecting the Australian claim.
The biggest current threat to Antarctic ecosystems is not mining but krill harvesting. While it is true that these small crustaceans exist in enormous numbers in Antarctic waters, harvesting by Japanese and Russian trawlers is quite possibly reaching a stage where species which depend on krill---seals, whales, penguins etc.---will be reduced in numbers. As a warning, overfishing has probably been primarily responsible for documented declines in Arctic bird and mammal populations in recent years.
In principle, we should be prepared to accept United Nations control of Antarctica, preferably as a managed-use park in the style of the Great Barrier Reef Marine Park. A Sydney firm of cold-climate architects, Helmut Rohde and Partners, has been designing an environmentally sensitive tourist centre for Antarctica for some time which includes portable self-contained energy-efficient buildings and a year-round ice runway for large planes. If such ventures could be guaranteed not to grow and not to affect bird and animal numbers, they should at least be regarded as an option. On equity grounds though, any such limited tourist access, if ever approved, should not be rationed by price.
Drawing boundaries in the seas between Australia and her various neighbours is a complicated business and only just finished in the potentially oil-rich Timor Sea between Australia and Indonesia. The agreement there for a `grey area' where oil ventures will be undertaken jointly by the two countries is a sensible compromise (albeit an unequivocal acceptance by Australia of Indonesian sovereignty over East Timor).
Learning from others
One of the advantages of a federal system of government is that the member states can learn from each other's experiences. Similarly, Australia can and must learn from the resource-management experiences of other countries.
Historically, the United States has pioneered several institutional arrangements and social technologies which we have quickly adopted. The Royal National Park near Sydney was the second national park in the world, declared several years after Yellowstone; the New South Wales Soil Conservation Service started soon after that of the USA.
In 1970 the US congress passed a National Environmental Policy Act. This proved to be landmark legislation which
laid the ground rules for environmental protection both in the United States
and other countries. The Whitlam
Government, under the guiding hand of its Minister for Environment and
Conservation, Moss Cass, enthusiastically
adopted its own version of the US legislation in the Environmental Protection (Impact of Proposals) Act 1974. In my opinion this Act has, in itself, been a near total failure. It has however spawned several State Acts which have been considerably more successful. The point is that by being aware of resource-management innovations in other countries, not necessarily with similar political structures, we have the chance to identify, and vicariously test, innovations---social technologies---for tackling our own problems.
But do we need formally to foster such a monitoring capability? Australians travel a lot and, in academic circles at least, keep well abreast of the professional literature. Probably some awareness of most overseas developments is usually present somewhere in the system, but the machinery for alerting and briefing the State and Federal decisionmakers who could decide to adapt and adopt such developments is lacking.
The obvious conduit for such diffusion is the established system of ministerial councils where State ministers with comparable responsibilities meet periodically to discuss matters of common interest and, sometimes, co-ordinate actions or legislation. For resource management, the most relevant ministerial councils are probably Council of Nature Conservation Ministers, Australian Environment Council, Australian Agricultural Council, Australian Soil Conservation Council, Australian Forestry Council. These councils are backed up by a powerful system of standing committees and various working parties.
The need is for a social technology where academics, resource-management professionals and the public are regularly invited to make suggestions for improving resource-management arrangements. This could be done, for instance, through a Ministerial Councils Advisory Committee given the single task of scrutinising current approaches to resource management and formulating options for alternative approaches. This Committee would report to all relevant Ministerial Councils, reflecting the perception that resource management cannot be tackled only on a sectoral basis. For example, the Advisory Committee, if it were functioning now, might be reporting on the success and relevance of America's experiment with conservation reserves wherein farmers are paid to retire unproductive land under threat of degradation.
This is not the place to develop the Advisory Committee idea. The more important point being made is that, in its existing ministerial councils, Australia has its best chance of co-ordinating and collectively improving resource-management institutions. They are something to build on; we do not have to start from scratch.
At the other end of the resource-management spectrum, it is important that recent graduates and young resource-managers get every chance to travel, both inside and outside Australia, to see how things are done elsewhere. It is so much more efficient to learn from other people's mistakes than your own.
New Zealand is a good model of and for a progressive Australian State. They established something like our Commission for the Future years ago; they have grappled with drafting national land-use policy. New Zealand loggers and conservationists have recently shown Australia how diverse interest groups can reach agreement on an issue as delicate as the allocation of native forests.
Their institutions and values are close to ours but different enough to produce novel proposals for programs, policies, institutions etc. Certainly their unitary government system makes national programs easier to implement, but we shall be wise to monitor resource-management developments there. For example, they are at present undertaking a major reform of resource-management law, with the intention of redesigning their total system of management of natural and physical resources.
New Zealand does in fact have membership or observer status on several Australian ministerial councils, including the Council of Nature Conservation Ministers and the Environment Council. Unfortunately, the reason seems to be more one of the New Zealanders taking the opportunity to learn from our mistakes and initiatives than the reverse.
The relevance of Canada to Australian natural resource management is that it is another big empty federation with a resource-based economy. Both countries are having to learn, and can learn from each other, for example how to negotiate resource-use agreements with transnational corporations. Temperature differences cannot disguise the similarities between their North-west Territories and northern Australia, including the presence of underprivileged indigenous peoples.
Like the New Zealanders, the Canadians are well ahead of Australia in their attempts to think through the principles, the policies and the institutional arrangements needed to manage their natural resources better. For example, environmental impact assessment procedures have been particularly well developed in Canada. Also, it was Canadian researchers at the University of British Columbia who developed the collection of concepts, techniques and procedures known as Adaptive Environmental Assessment and Management, and intended to facilitate the design of creative resource-management and policy alternatives.
A recent analysis of major issues in Canadian land use points up the similarities with the Australian situation. Identified major issues were
* ecosystem maintenance;
* loss and degradation of prime agricultural lands;
* forest-land maintenance;
* loss of wildlife habitat;
* access to energy and mineral resources;
* coastal zone issues;
* northern development and conservation;
* issues of ownership and control;
* anticipating future land requirements;
* influencing the decisionmaking process;
* management of increasing demands and conflicts.
The importance of Sweden is that it is a country which appears to be able to develop significant policies democratically and then set about implementing them without bogging down in a welter of rearguard actions by echelons of special-interest groups. They are decisive without being dictatorial.
Quite apart from their progressive social welfare policies, which are admirable but outside the focus of this book, they have been able to implement progressive environmental policies such as a staged reduction in the use of hazardous agricultural chemicals and the decommissioning of nuclear power stations.
Sweden is another small resource-based economy, or, more precisely, one which has moved from resources to resource processing to supporting industries. They may have lessons for us because of that, but I think the single most important thing we can learn from them is the value of giving people as extensive an education as they can absorb.
4. PATTERNS IN THE DUST: CURRENT LAND USE
The reason why it is important to have a good understanding of how Australia is used at present is that we have to get to where we are going from where we are. In 50 years, very large parts of the place are going to look, at least superficially, similar to how they look today. Towns and cities may be bigger and built in different styles; there may be some flash new infrastructure like very fast trains around; certainly more people; some new mines; more parks; changes in farming patterns, hastened perhaps by climatic change and land degradation; more plantations and fewer clearfelled forests; and so on. The point is that, God willing, what we see will be in a clear evolutionary line running back to 1990.
To help paint a succinct picture of how Australia is used, it is convenient to think of the country as divided into seven overlapping settlement regions:
* The Ecumene
* The Farmlands
* The Sparselands
* The Coastal Zone
* The High Country
* The Forests
* The Mineral Enclaves
Each of these has a distinctive endowment of natural resources, opportunities and environmental constraints which has acted with social and economic imperatives to induce characteristic patterns of settlement and land-resource use. The patterns however are not rigid. The level and type of human activity has and will change over time in each region and, to some extent, region boundaries (which are pretty fuzzy anyway) will move as population grows and as industries come and go.
is a mellifluous appellation for that part of the country where most
Australians live (Map 4.1).
Alternatively, it is that part of the country where the population
density exceeds a value arbitrarily defined as `very low'. Table 4.1 shows the number of people living
within half a day's drive
(150 km) of 18 points selected in such a way as to include as many Australians as possible. Some 92.8% of the 1981 Australian population lived in one (or more) of these circles. There are four million people living within half a day's drive of Penrith (western Sydney) for example.
Rank and Name Population Cumulative
1. Sydney 4 004 764 27.5
2 Melbourne 3 411 567 50.9
3 Brisbane 1 605 140 61.9
4 Adelaide 1 117 064 69.6
5 Perth 1 021 054 76.6
6 Canberra 481 689 79.9
7 Tasmania 398 804 82.6
8 North Coast (NSW) 255 406 84.4
9 West. Dist (Vic) 205 733 85.8
10 Sunshine Coast 162 791 86.9
11 Townsville 154 356 87.9
12 Rockhampton 123 821 88.8
13 Central West (NSW) 118 727 89.6
14 Riverina 111 976 90.4
15 Mackay 96 042 91.0
16 Gippsland 94 754 91.7
17 Cairns 89 668 92.3
18 South Coast (NSW) 75 194 92.8
The total area, excluding overlaps, of these 18 regions is 1.04 million sq km, about 14% of Australia. This represents a population density in the Ecumene of 13 people per sq km and a population density elsewhere of 0.15 people per sq km. For comparison, Bangladesh has a population density of 760 people per sq km, the USA has 25 people per sq km.
Capital city dominance
Capital city dominance has been the outstanding feature of Australian urbanisation since the middle of the 19th century. The proportion of the country's population living in the State capitals increased almost without interruption to reach 63% in 1971 where it has since more or less stayed.
Why do the majority of people live in the capital
cities? Initially, it was a reflection of the difficulty of pushing intensive
occupation into a harsh hinterland from a few widely separated coastal
footholds. Then, so Geoffrey Blainey has
argued, the emerging pattern was reinforced by wool and gold becoming
Australia's main 19th-century exports.
Wool-growing districts were too thinly populated to give rise to
commercial towns and migrants were encouraged to settle in the main
gold mining created concentrations of population in inland areas, the port cities gained added momentum from the trade and wealth generated by gold. The continuation of the trend into the 20th century has been fostered by industrialisation and the growth of tertiary employment, both preferentially based in metropolitan areas.
It is an extraordinary settlement pattern by world standards, yet is not so unusual if one thinks of the Ecumene as being `Australia', with the Perth region an `island' separated from the East by an ocean, albeit one of red dirt.
Pros and cons of an extraordinary settlement pattern
The pros and cons of massive population concentration are difficult to sort out definitively. As individuals, we want to live in places which are interesting and convenient. If we were more dispersed we would experience fewer of both the economies and diseconomies which go with larger settlements: reduced travel costs, more crime, easier access to higher-order services, more pollution etc. If we were more dispersed, attempts to develop agricultural and mining enterprises outside the Ecumene would be less likely to founder because of the lack of infrastructure, particularly ports, roads and railways. On the other hand the very lack of people and activity outside the Ecumene is rapidly coming to be viewed as an asset, particularly by the landscape-based tourist industry. People numbers and energy consumption are the triggers which initiate stress on natural resource systems and, by world standards, ours remain in a reasonably natural state outside the Ecumene.
The above sort of debate is somewhat pointless unless it is to be used to guide the location of the extra population to which we are committed over coming years. Such guidance as there is at present occurs at local rather than at State or Federal Government level. We have no national settlement strategy (see Chapter 8). Shires, municipalities and metropolises attempt to steer whoever arrives into new housing developments, commonly sited by commercial developers with little consideration of the social costs and benefits of their decisions. With a myopic eye to rating revenues, few local authorities are interested in minimising local population increase. The Federal Opposition recently talked of encouraging migrants to settle in the Northern Territory, but not with a great deal of conviction.
Australians are fairly footloose; the average Queenslander moves every five years and the average Northern Territorian even more frequently. In State terms, according to recent censuses, a slowly increasing proportion of the population is living in Queensland and Western Australia although populations of other States are still increasing in absolute terms.
For the next few decades at least, despite
relatively greater recent increases in non-metropolitan populations, factors
promoting urbanisation and centralisation are likely to outweigh factors
promoting decentralisation (i.e. migration out of the larger cities), even
though the marginal social costs of further centralisation are probably
ever-higher. And this growth will be
largely within the Ecumene. Why? The Ecumene contains the bulk of Australia's
industrial (ports, railways, power stations), urban (schools, hospitals
etc.) and social (services, skills etc.) infrastructure. For most enterprises, development costs and operating costs are likely to be lower there. The only reasons for going outside the existing Ecumene are to exploit immobile resources (minerals, forests etc.) or to enjoy a different spectrum of amenity values (recreation, retirement etc.).
Within the Ecumene, it is the coastal settlements between Cairns and northern New South Wales which are going to grow most obviously and painfully. Perth is under something of a Greenhouse cloud, particularly in terms of water supplies, and has a more problematic future.
Impacts of urban growth
Concentrations of people impose a range of demands on the more or less fixed resources of the surrounding countryside. For example
* Demands for roading and building materials, which are expensive to transport, focus around urbanising areas.
* Developers have a penchant for ecologically sensitive areas such as dunes and for `creating' land by filling in swamps.
* Pollution problems emerge, basically because the limited assimilative capacities of regional airsheds and watersheds get `overloaded'.
* The growth of cities frequently increases the cost of supplying fresh produce (milk, fruit, vegetables etc.) to those areas. Housing and farming both have a preference for level, well-drained soils and developers can pay more for land than farmers. Farmers are forced out into areas where transport and other costs are higher. While Australians have a liking for living on urban `quarter-acre' blocks, this does impose external costs on near-city farming, not to mention the higher costs of infrastructure provision compared with medium density urbanisation.
Inside cities there is a further set of resource-management problems concerned with such issues as transport systems, recreation areas, facility location. These are important and interesting but too detailed for this book. At the other end of the scale, the strategic issues of managing total population growth and the possibilities for extending or redesigning the Ecumene are considered elsewhere, primarily in Chapter 8.
One indirect impact of urban growth warranting more extended comment is on the rate of infrastructure replacement, both within and outside metropolises.
At the 1989 conference of the Institution of Engineers, Lex Blakey warned of an impending plunge in living standards and business efficiency due to the decay of public structures such as roads, sewers and telephone systems. He estimated that annual spending on maintenance would have to increase fourfold over the next quarter century to halt the decay. Infrastructure replacement is indeed becoming an important issue in Australian urban development. Nationally, 80% of present roadworks budgets will be needed for maintenance of the road system by the end of the 1990s. Given the slow growth in budgets for infrastructure, the implication of major increases in maintenance needs is that there will have to be major reductions in funds for expanding and upgrading purposes. The South Australian Parliamentary Public Accounts Committee estimates that by 2010 replacement expenditure will swallow up all of today's capital spending budget for that State.
Slowing the rate of population increase would be an effective way of making infrastructure budgets go further. The point is, urban growth is a very real threat to the quality of existing infrastructure. By not replacing infrastructure at the appropriate time, the present generation is imposing a burden on the next generation, a generation which is already destined to be burdened by having to support more retirees per worker than the present generation.
Synopsis of Australian agriculture
Australian agriculture is more highly specialised than that of most other countries. The small size of the population in the 19th century meant that large quantities of a commodity could only be produced if it were produced for export. Large export markets could only be found for a limited range of products which would not deteriorate during transport to European markets. The lack of cheap labour further restricted the range of commodities to those which could be produced using little labour. Even today 80% of Australia's agricultural output consists of wool, wheat, beef, sheep-meats, sugar, butter and milk; these seven commodities are produced on highly specialised farms which seldom produce more than three or four commodities.
The actual commodities produced in any particular part of the continent are chiefly determined by the availability of moisture and, in the period of the year when precipitation occurs, temperatures. Map 4.2 shows Australia divided into 10 major agricultural zones; it is a slight variation on a fairly traditional delineation which has been used by Australian Bureau of Agricultural and Resource Economics for many years. It shows:
* The high-rainfall zones of Western Australia, Victoria-South Australia, Tasmania, New South Wales and Queensland. * The wheat-sheep zones of Western Australia, Victoria-South Australia and New South Wales-Queensland. The bulk of our major farm exports, wheat and wool, are produced in these zones. Wheat is mainly produced where the growing season is five to seven months; varieties capable of giving high yields in areas of high rainfall have not been developed and the topography and winter waterlogging of much of the high-rainfall zone (650+ mm) makes cultivation difficult. Beef and lamb are important too, products of improved pastures, i.e. fertilised and sown to productive species of grasses and clovers. In eastern Australia, these zones also contain the major irrigation schemes of the Murray-Darling Basin which produce most of our cotton (a rapidly growing export), rice and soft fruits.
* The enormous pastoral zone where wool (in the south and east) and beef are the dominant products. The usable portion of the south of the continent with a growing season of less than five months supports sparse cattle and sheep grazing (southern pastoral zone). North of the Tropic of Capricorn the whole of the continent is used for sheep and (mainly) cattle grazing, except for isolated areas on the Queensland coast (Queensland high-rainfall zone) which are used for dairying, or for producing sugar or tropical fruits.
North-central Queensland is traditionally part of the pastoral zone but is emerging as an area of potential agricultural expansion and intensification and is shown separately on Map 4.2.
In addition to the agricultural zones where the type of production is determined by the natural environment, 12 000 sq km of land are irrigated by water conserved in large reservoirs constructed by the various State governments.
The importance of agriculture in any discussion of land use in Australia is confirmed by the figures in Table 4.2.
Arid and semi-arid grazing 43.7
Unused land 26.0
Non-arid grazing 17.4
Extensive cropping 5.8
Nature conservation reserves 3.5
Transport corridors 1.2
Intensive cropping 0.3
Urban land 0.1
In the last 30 years the volume of Australian agricultural production and exports has doubled but the area of land farmed has increased by only 16%. That is quite impressive. The total number of all types of farms in Australia declined by 15% to reach 174 000 over the period 1957-8 to 1981-2 (this figure, by 1987--88, had dropped to 127 000). Over the same period, average farm size increased by 24% to reach 2800 ha and the rural workforce decreased by 19% to 389 000 (and is still much the same). Fewer people are working bigger farms more intensively. The area sown to pasture has doubled; sheep numbers have fluctuated but are at present about the same at 149 million as in 1957--8. Beef cattle numbers have also fluctuated and are at present about 24 million.
The major change in broadacre agriculture between the late 1950s and the late 1980s has been the near doubling, from a base of 100 000 sq km (half wheat, half other crops), in area cropped to 180 000 sq km. Why? Cropping has been more profitable relative to livestock production and there have been significant technological advances in crop agronomy, wheat breeding and machinery capacity. Expansion has generally been into regions of lower, more variable rainfall (less than 350 mm per annum), implying lower, more variable returns. Also, there has been a marked intensification of cropping in more favoured areas of temperate and subtropical Australia. In the subtropics there have been large increases in area of summer crops such as sorghum, sunflower and soybeans.
One consequence of crop expansion into marginal country and of problems associated with intensification of cropping (meaning percentage of years that a crop is grown on a paddock) in more favoured areas has been declining productivity. Productivity is the ratio of outputs obtained to inputs used. Despite substantial increases in inputs used in the wheat industry (machinery, herbicides, pesticides, new varieties etc.) the average annual increase in yields over the 1970s was a mere 1.8%. Productivity in the sheep industry, on the other hand, has increased substantially over the same period, largely due to an increase in sheep run per worker.
During the 1970s and early 1980s, a period of continuing decline in farmers' terms of trade (prices received for outputs relative to prices paid for inputs), the rates of return to capital and management (excluding capital appreciation) on wheat, sheep and beef farms have averaged 5.0%, 3.8% and 2.1% respectively. Not exactly startling.
Table 4.3 summarises the value of agricultural production for each agricultural zone, by 13 product categories, for the period 1983--87. The southern (28.7%), northern (12.2%) and western (10.1%) wheat-sheep zones and the southern high-rainfall zone (17.7%) dominate Australian agriculture by this measure. The surprisingly low contribution of the New South Wales high-rainfall zone is probably due to the under-recognised burden of extremely acid soils in many places.
House paddock: the Murray-Darling
If the Ecumene is Australia's front garden, the Murray-Darling Basin (M-DB) is the national farm's house paddock. The catchment of Australia's most extensive river system occupies about a seventh of the continent (see Map 4.2) and produces about a third of Australia's total output from natural resource based industries. It supports 10% of the human population, a quarter of the nation's cattle and dairy farms, about half of its sheep and cropland, and almost three-quarters of its irrigated land. It includes large parts of the northern and southern wheat-sheep zones and part of the southern high-rainfall zone, the three most productive farming areas in the country.
C ropping intensity has been increasing steadily in
recent years in all except the wettest and the driest parts of the Basin, viz.
the dry rangelands of the Western Division of New South Wales and south-west Queensland
and the cold wet Southern Tablelands/Southern Highlands. Expansion rates
in recent years for areas sown to wheat in the Basin have been highest in north-western New South Wales and the western Darling Downs. In northern New South Wales and Queensland, where both summer and winter crops are possible, four crops (two summer, two winter) in five years are regularly achieved. Also, in limited areas of Victoria (e.g. parts of the Wimmera), there are a significant number of farmers who have sold all their livestock, often removed fences and established high-intensity cropping systems.
Two of the four regions in Australia where more than 10% of the total land area is regularly under crop are in the Murray-Darling Basin (Table 4.4). All four are suffering land degradation problems of one sort or another.
1. WA wheat belt 26
2. Upper Darling Basin 14
(NW Slopes and Darling Downs)
3. SA western and northern counties 10
4. Murray Basin 10
(Murray Basin Slopes, Murray Plains)
The Upper Darling Basin;
The northern third of the Basin has
undergone dramatic changes in land use, in terms of both diversification and
intensification, since the second world war.
These include steady increases in the production of winter grains,
massive increases in summer grains and, more recently, cotton and
oilseeds. Total livestock units have
increased by perhaps 50%. Increased use
of fertilisers and irrigation water have been the driving forces in this
transformation. The options of running sheep or cattle and growing summer or winter crops make this the most flexible extensive farming area in the country.
The average wheat yield on the Darling Downs in the north-east of the Basin is nearly five times the national average. The Downs is commonly presented as a highly productive and efficient farming district, yet an average of four to eight mm of rich black earth is lost there each year as a result of soil erosion. At this rate, the fertile topsoil will be exhausted in 30 to 50 years. Over 10 000 ha have already been retired from cropping due to irretrievable erosion damage. Many of the upland farms in the Downs are small and probably only marginally economic. Consequently, farmers find it difficult to afford adequate conservation measures and to avoid cultivating the steeper (erodible) upper slopes. Ignorance and apathy play a part too.
Apart from erosion, which is well recognised, the Upper Darling Basin may be on the verge of experiencing more of the land degradation problems already being experienced further south. The intensification of the last 40 years has opened the way to salinisation, loss of soil structure and soil acidification. The input--output balances of water in the landscape have been massively changed and new equilibria have not been established. Current interest in the use of effective new arboricides to clear the poplar box woodlands, here and further north, will certainly increase short-term stock-carrying capacity but may also eventually induce extensive dryland salinisation. The link between tree clearing and dryland salinisation is comparable with that between smoking and lung cancer. It cannot actually be proved but giving up seems like a good idea. Table 4.5 summarises clearing activity since European settlement.
1988 1988 1788 1788
Area Area Area Area
(sq km) (%) (sq km) (%)
& Graminoids 340 393 32.7 46 416 4.5
Shrub lands 134 582 12.9 184 322 17.8
Low trees 230 592 22.1 262 204 25.3
Woodlands 283 262 27.2 389 697 37.6
Forests 51 973 5.0 154 535 14.9
Pine forest 1 210 0.1 - -
The economics of irrigation schemes in the Basin have been strongly challenged by a number of authors. Bruce Davidson in Australia wet or dry (1969) draws attention to the massive infrastructure cost (channels, dams etc.) associated with setting up irrigation schemes and argues that using the same capital to extend and intensify dryland farming in southern Australia would have been far more beneficial to the national economy. Furthermore, at the time Davidson made this argument, the subsequent massive problems of soil salinisation and silting up of dams in irrigation areas had not emerged. Davidson's `opportunity cost' argument is analogous to the one he used so effectively in The northern myth (1966) to argue against intensive agricultural development (including irrigation schemes) in northern Australia. It seems unlikely that any more large irrigation dams will be constructed in the Murray-Darling Basin; the task facing us now is to keep the existing schemes viable.
Should this include keeping water charges to farmers down? A number of economists have argued that governments have historically underpriced irrigation water and it is only when water is priced according to its economic cost that irrigators will be encouraged to reduce water use and hence the salinity problems caused by overwatering. The correct price to charge for a resource which is almost fully used is the long-run cost of supplying another unit of it (long-run costs include capital costs as well as running costs). Even then, as John Williams points out:
It is practically impossible to irrigate and not have some water pass beyond the root zone ... The implication for this is that irrigation can in no way be sustainable without subsurface drainage as part of the irrigation infrastructure ... In time salinisation will take place if adequate drainage and disposal is not provided. The problem of salinity in irrigation will move from the problems of the Goulburn valley to Emerald and onto the Burdekin.
There has been a trend in the last decade to introduce transferable water entitlements into the Murray-Darling Basin, so far only for water pumped directly by private diverters. To quote Don Blackmore, Chief Executive of the Murray-Darling Basin Commission:
It is inevitable that transferable water entitlements will become a reality within the next decade. They are needed to formalize the market in water which already occurs via land sales. The development of transferable water entitlement policies can only enhance efficiency of water use and be of value from both an economic and environmental perspective. Transferable water entitlements will also provide significant salinity benefits in that water will invariably flow from the western more saline side of the Riverine Plain to the eastern side.
It does need to be noted however that there are peculiar difficulties in creating water markets. Water resources are both public and private goods. A public good such as a river view or a healthy swamp is not marketable. It follows that if all water in a river is privately owned, there will be under-investment in such public goods. Before correcting for this, the difficult task of comparing the values of instream and offstream uses would have to be tackled. A further difficulty with water markets is that water transfers will not automatically protect third-party (downstream) interests and a social technology for ensuring this would be needed.
Privatisation of irrigation-supply infrastructure has been advocated both by governments wishing to be relieved of maintenance burdens and by farmer organisations smelling the chance to pick up assets at bargain prices. A survey by John Pigram and Helen Mulligan suggests that individual irrigators are not nearly so keen.
Competition for land and water
It has been fashionable for some time to regard the `natural unit' for managing land resources as the river basin or, for smaller areas, the stream catchment. The argument is that because water flows downhill, what happens in the upper part of a catchment (e.g. water pollution, salinisation, damming) affects what happens in the lower catchment. Therefore decisions on activities in all parts of the catchment should be made simultaneously and with regard to their interdependence. This seems reasonable to all parties except those high in the basin. They are the only ones who cannot suffer from upstream decisions.
The Murray-Darling Basin Commission, representing New South Wales, Victoria, South Australia and the Australian government (Queensland has observer status) is an heroic attempt to implement this philosophy. South Australia is heavily dependent on the quantity and quality of Murray water coming from Queensland, New South Wales and Victoria. The Commission's impossible task is to reliably provide all `stakeholders', instream and offstream, with the quantity and quality (in terms of salinity, nutrients and turbidity) of water they want by storing and releasing it according to a definite strategy. In addition, they have to worry about a rapidly ageing water-supply infrastructure.
For example, the Basin's irrigation industry, overlapping the Ecumene as it does, is likely to come under considerable pressure as the Basin is asked to play a larger role in providing urban water, including water to cities which are not even in the Basin, e.g. Melbourne. Adelaide, a city of over one million people, uses about 170 GL of water a year, with an average of 35% being derived from the Murray. In dry years this rises to 90%. Conservationists want regular flooding of the Macquarie Marshes and, to ensure river redgum regeneration, the Barmah Forest. Fishermen want access to full reservoirs. Water-thirsty pulp mills are needed to process pine logs from plantations in the south-east of the Basin. Big cities such as Albury and Canberra use the river system as a sewer. So it goes on.
All this from a river system which carries little water by world standards. And it is not just surface water which has to be managed. For example, around the rapidly growing urban centre of Tamworth in the Namoi Basin both intensive irrigated agriculture and the city's domestic water supply compete for the same limited groundwater supplies.
of the Murray-Darling. The Murray-Darling Basin's rivers are highly
regulated with storage volumes equal to 1.36 times annual flow. As a consequence the average flow at the
Murray mouth has been reduced by about half.
From the headwaters to the terminal lakes, the salinity of the Murray becomes progressively more influenced by the natural inflow of highly saline groundwater. These natural inflows have been increased and will be increased still further in coming decades as a result of both irrigation and dryland farming practice. Despite the Commission's Salinity and Drainage Strategy, changes already in place are likely to cause increased salt levels in the river over long periods of time.
What can be done? Reafforestation is normally promoted for its effect on dryland salinisation, but it should also have some effect on river salt levels. Another approach to reducing recharge of the salty regional aquifers which eventually end up in the river is to evaporate salty water off in selected `sacrifice' areas. What this allows is a tradeoff between really buggering a small area and somewhat degrading larger areas! Better irrigation practices and changes in water allocations have a part to play. There is also the strategy of praying that flow in the Darling, at least, will increase manyfold under the Greenhouse effect.
Overall, there is no clear strategy, no quick technological fix, for managing river salt levels. The problem can only be tackled by a mix of actions, none of which can have dramatic effects.
The Basin's land resources are similarly subject to an increasing range of demands including the need to conserve remnant vegetation communities, establish a meaningful system of conservation reserves, and provide land for newer uses such as extensive recreation areas, hobby farms and timber plantations. The Commission is putting considerable emphasis on the formation of community groups which will identify key aspects of environmental degradation in their localities and develop and implement plans to address these. Alistair Gilmour sees these committees as `the most important innovation in environmental management in Australia in recent years'.
Beefing up the Commission. Be assured, the Murray-Darling Basin is in trouble. Its land, water and biotic resources have been already or are threatened with destruction, degradation, pollution and exhaustion. We must have the courage to say that draconian measures are needed to save Australia's agricultural cornucopia. At least let us admit that strong action is an option. In the future, there must be multi-objective co-ordinated management of water, land and biotic resources, with the primary goal of managing these for the benefit of the whole community, not for special interests. This requires that the rights and duties of individuals, industries, towns and States with respect to water resources be clearly defined at the highest level. The recently strengthened Murray-Darling Basin Commission is our best hope. The New South Wales Soil Conservation Service has initiated a program of Total Catchment Management but it gives every impression of being a toothless tiger armed only with a jawbone.
The Murray-Darling Basin Commission is trying to establish its legitimacy at the moment, particularly in Queensland where little local need for such a body is seen. It is to be hoped that the Commission is soon in a position to consider and perhaps implement, by one means or another, a Natural Resources Management Strategy incorporating policies such as the following:
* a moratorium on further clearing of native vegetation in the Basin;
* selective re-establishment of trees in areas where this would have maximum effect on the spread of dryland salinisation;
* purchase of cropping rights in marginal areas;
* imposition of erosion-retarding cropping practices;
* transferable water rights;
* a network of evaporation basins;
* water to be sold at full cost including amortisation of headworks;
* no new cities and carefully controlled expansion of exsting regional centres;
*detailed environmental impact assessment of all proposed new industrial projects;
* projects involving irreversible devaluation of natural capital to be offset by projects to conserve other natural resources under significant threat;
* a major land allocation exercise covering conservation, recreation, tourism, timber plantations, industrial infrastructure etc.
These are purely examples. Setting up and implementing an effective natural resources management plan will be a major exercise. Getting the necessary political support and setting policy instruments in place will be at least as important as deciding how these are to be used.
Bottom paddock: the South-west
Agriculture is the most extensive land
use in the south-west corner of Australia.
Inland, the light
soils were developed rapidly after the second world war, using large machinery to clear the bush for cultivation. The agricultural system is based on winter-growing annual crops and pastures. The crops are mainly wheat or other cereals, and the pastures carry sheep, and occasionally cattle. Farms are large, often more than 1000 ha, and production per unit area is low by international standards. This low production is associated with low-rainfall, short growing seasons, and low fertility of the soils. Phosphorus fertilisers, and, on sandy soils, some trace elements must be applied to maintain yields.
Agriculturally, the region may yet contract as fast as it expanded; dryland salinisation is taking 250 sq km a year out of production and the region is earmarked for increasing aridity under current Greenhouse scenarios. Salt from rising water tables in agricultural areas has been leached into the rivers which flow from the Darling Plateau to the coastal plain. The Murray River (the Western Australian one) is now brackish. The large Swan and Blackwood Rivers, which were once fresh, are now too saline to be dammed for agricultural use or human consumption. This is environmental degradation on a tragic scale.
Agriculture and other land uses
Clearly, the present agricultural systems in parts of the Darling Plateau are incompatible with the production of potable water for Perth. Moreover, conflict between whole-milk production needs and urban needs for water are intensifying as Perth's population grows. Similarly, the vegetable industry on the dunes north and south of Perth is also facing urban competition over its use of shallow groundwater for irrigation.
Not all the land-use problems in the South-west involve agriculture. The Jarrah forests of the Darling Plateau have multiple functions including water-resource protection, timber supply, conservation and recreation. The western Darling Plateau is being extensively mined for bauxite which is exacerbating the spread of the root-rotting Cinnamon Fungus (Phytophthora cinnamomi). This fungus causes Jarrah dieback, now affecting 10% of the region's forests.
With respect to flora and fauna conservation, only 7% of the wheat belt still has native vegetation and much of this is heavily degraded and losing both plant and animal species. Extraction of large quantities of groundwater on the coastal plain will dry up the chain of biologically and recreationally important shallow lakes which run north and south of Perth.
In the south-west corner of the country there are clear signs that diverse demands for the use of natural resources are overtaking the capacity of the region to meet those demands.
... and the rest of the farm
Take out the Murray-Darling Basin and the south-west of Western Australia and the rest of the farm largely comprises the rangelands, the eastern coastal fringe (the high-rainfall zones) and the summer rainfall areas of central and north-central Queensland.
Agriculturally speaking, the high-rainfall zones, where soil waterlogging is more likely to inhibit plant growth than soil dryness, range from the sugar lands of Cairns to the superfine Merino country of southern Tasmania.
The intensively farmed parts of the Queensland
high-rainfall zone comprise the wet tropics of Cairns-Ingham, the Atherton
tableland, the Burdekin, Mackay-Proserpine and Bundaberg-Maryborough. Apart from the recently deregulated sugar
industry, the backbone of the north Queensland economy, they supply fruit and
vegetables to much of eastern Australia, particularly in winter. The range of crops which are beginning to be
grown in a small way (e.g. coffee and tea) or experimentally is large and
prospects for the Queensland high-rainfall zone are excellent. Soil erosion (because of steep slopes and
intense rainfall) is a potential problem in large areas and an actual problem in
many banana and pineapple plantations, even those
on well-structured kraznozem soils with a great capacity to accept water.
Elsewhere in the high-rainfall zone, farming systems are well-established and without the overwhelming problems of so much of Australian agricultural industry. By the same token, prospects for large output increases are not obvious. Winter wheat for grazing and grain on the arable parts (say a third on average) of properties in the high-rainfall zone is an interesting possibility. After all, Tasmania was once the granary of Australia! Livestock production based on productive improved pastures is particularly important. The key to the relatively high standards of land management in the high-rainfall zones is that the land is valuable enough per unit area to warrant expenditure on improvements and, in the face of degradation, preventive and ameliorative measures.
Central and north-central Queensland
North of the Murray-Darling Basin, and largely in the northern wheat-sheep zone, are the established cropping areas (grains/oilseeds, cotton) of the central highlands and the Dawson-Callide valleys of the Fitzroy Basin, and it is around the margins of these areas (as well as the edges of the Upper Darling Basin) that dramatic increases in crop area have been occurring. For example, between 1980 and 1984 the area of crop in Belyando shire (Clermont area) increased from 41 000 ha to more than 106 000 ha. While considerable potential for further westward and northward expansion certainly exists, the rate is likely to be dampened by the problems of developing stable farming systems in these climatically variable areas, the lack of suitable crop varieties and inadequate marketing facilities.
Also throwing emphasis back to livestock farming is the continuing improvement in the range of pasture species available and the advent of efficient new tree-killing chemicals. There is a danger here. Clearing woodland on low-fertility soils raises its short-term carrying capacity but all too frequently leads to loss of fertility and the invasion of unpalatable species.
Most of Australia, 82%, has a population density of less than 1000 people per 8000 sq km and qualifies as sparsely populated, as what John Holmes calls the sparselands (Map 4.1). There are no precise boundaries but the sparselands are essentially those parts of Australia outside the area identified above as the Ecumene and they therefore include a few isolated urban and mining centres such as Alice Springs, Broken Hill and Mt Isa.
Most of the sparselands can be further described as rangelands meaning that they are largely used for grazing sheep and cattle on native vegetation. In this sea of pastoralism, occasional islands of mining, urban and tourist activity appear. Climatically, the sparselands include the central arid zone, its surrounding semi-arid zone and the wet-dry tropics (five months wet, seven months dry) of northern Australia.
Discussion here of how the sparselands are used and the functions they perform will be divided into a general perspective on the pastoral industry followed by more focussed sections on (a) the Arid zone and (b) the North.
Mainly sheep and cattle: the rangelands
Australia's pastoral zone or rangelands, to use the American term more common nowadays, occupy about two-thirds of the continent and are used for sheep and cattle grazing on native vegetation (63%), vacant Crown land (21%), Aboriginal lands (12%), conservation (3%) and defence and other uses (1%). Sheep are mostly run in the more southerly parts of the rangelands where they are supposedly protected from predatory dingoes by a 9 960 km long wire fence stretching from central Queensland to the Great Australian Bight.
The pastoral industries are organised into very large management units; the average size of sheep properties is 210 sq km and cattle properties are much larger, averaging 2500 sq km. Practically all of the country's 4000 plus pastoral properties are held on long-term leasehold tenure, either by absentee investment companies or family-owned and -operated enterprises. The three largest pastoral companies in Australia are Stanbroke Pastoral Company Pty Ltd owned by the AMP Society, Australian Agricultural Company with Colonial Mutual as majority shareholder, and Janet Holmes a Court's Sherwin (Heytesbury) Pastoral Company Ltd. Their comparative statistics in 1988 were as follows:
Stanbroke Australian Sherwin
Area ('000 sq km) 94.2 58.8 82.9
Cattle ('000 head) 317.7 259.1 290.5
Sales ($m) 34.0 31.5 28.7
Expenditure ($m) 16.6 21.9 44.0
Pre-tax profits ($m) 16.0 11.6 -14.0
Net assets ($m) 83 142 83
Most properties are fenced into a few large paddocks with one or several watering points. Water is provided by drilled wells equipped with windmills or by surface catchment dams. Particularly in the cattle industry, but also in the sheep industry, stock movement is controlled as much by the distance between watering points as by fences. Shepherding is not practised. Pests and diseases are minimal so that handling of animals is reduced to lamb marking and shearing (sheep) and branding and selection for sale (cattle).
Matching stock numbers to available feed is the major ongoing decision facing pastoralists. Do you start destocking after three dry months? four? five? Not only is feed-producing rainfall variable, but it is not generally recognised that feed production varies more than proportionately with rainfall. For example, when the rainfall received in a particular year is half the median, forage growth may be reduced to one-quarter.
The basic nature of Australian pastoralism is such that there are fewer operations to upgrade than there are for agricultural production in higher rainfall areas. Fodder conservation is generally regarded as uneconomic, although the idea of setting aside `plantations' of mulga or saltbush as `living' drought reserves warrants further analysis. A technology permitting moveable watering points as a way of spreading grazing pressure would be welcomed. Proven successful rangelands management technologies identified by Barney Foran and others include
* tick resistance and heat tolerance in cattle;
* use of aircraft and motorcycles for mustering;
* improved radio communications;
* polythene pipe and pre-cast storage tanks;
* trap yards and automatic stock-weighing facilities;
* low-cost electric fencing systems;
* `pour-on' parasite control;
* remote electronic monitoring of stock waters;
* prescription burning for pasture management;
* mineral supplements;
* computer-aided livestock marketing;
* multi-decked roadtrain transport;
* genetic gains in animal productivity.
The practical challenges are to increase labour productivity and maintain---not increase---carrying capacity. Increases in labour productivity have indeed been significant but the concomitant, given worsening cost:price ratios, has been to increase the amount of land needed for a viable owner-operator enterprise. Fortunately, restrictions in several States on maximum areas which can be leased by one person are being relaxed, albeit administratively rather than legislatively. South Australia has no limit on the amount of land which can be leased by one person.
Allocation and property rights
The issues which dominate discussion of management of the rangelands are almost exclusively concerned with some aspect of property rights, i.e. who is or should be entitled to do what, when and where, in the rangelands.
For example, an excellent 1981 report on the administration, management and tenure of South Australia's pastoral lands has major sections on:
* tenure systems;
* public access to pastoral holdings;
* conservation reserves;
* ownership of improvements;
* lease transactions;
* lease rentals;
* mining rights and access;
* Aboriginal rights.
New South Wales and Queensland rangelands are almost totally devoted to grazing compared with about half being used in this way in other States. The States with the high percentages of vacant Crown lands are Western Australia (38%) and South Australia (26%). The States with significant proportions of their rangelands assigned to Aboriginal use are the Northern Territory (27%), South Australia (15%) and Western Australia (10%). The only States with more than two per cent of their rangelands in conservation reserves are South Australia and Western Australia.
While Aborigines hold the largest proportion of Australia's rangelands after pastoralists, most of their land has poor prospects for viable grazing enterprises. When colleagues and I first reached this conclusion, I thought it made an interesting contribution to the land rights debate, but no one wanted to know. Aboriginals do not necessarily want to use their lands for pastoralism of course but it is true that lands which are among the more productive for pastoralism will usually be more productive of native plant and animal foods.
In that study, about 24% of the rangelands has been categorised as having high viability prospects (meaning it is capable of surviving climatically and financially hard times) and 41% as having medium viability prospects if used for pastoralism (Map 4.3). About 89 000 sq km of this total remains ungrazed, two-thirds of which is vacant Crown land in Western Australia and South Australia (Map 4.4). This area, along with the 250 000 sq km still available for development as cropland or for improved pasture (largely in Queensland), constitutes Australia's last agricultural `frontier'. Whether the frontier should ever be pushed back is another question.
The ungrazed areas of the rangelands effectively
constitute an informal conservation `reserve' system for the various vegetation
communities represented there. Rangeland
types with the lowest percentage of their area currently ungrazed are the
Mitchell grasslands (1.0%), the semi-arid woodlands (1.4%) and the mixed-tussock grasslands (5.2%). Approximately 50 000 sq km would have to be withdrawn from grazing, Australia-wide to meet the arbitrary but recognised target of conserving five per cent of each of the 10 main rangeland types in each State where they occur.
Has pastoralism a future?
capacity. The advent of pastoralism initiated a
downward trend in the amount of standing vegetation across the rangelands. The degree of loss can be roughly inferred
from trends in stock numbers with time.
In all districts where this has been studied, stock numbers rise rapidly
to a high peak following settlement. An
even more rapid decline to about a quarter of peak numbers then occurs,
generally in a drought period.
Subsequently numbers stabilise at about a third to a half of their peak
value, but this stable value is maintained only by the development of additional
watering points which have the effect of increasing the area available to
stock. In the Western Division of New
South Wales, the great drought of 1901--02 brought sheep numbers down from 13.5
million. Since then, sheep numbers have varied between two and five million, never reaching the old totals.
Has the inherent capacity of the rangelands to carry domestic livestock decreased in the last hundred years? Answering this question is complicated by the effects of runs of good and bad seasons and changes in uncontrolled grazing pressure, viz. increased numbers of rabbits and kangaroos. A run of good seasons can mask a slow decline in long-term carrying capacity.
For example, would it be possible to increase stock numbers in the rangelands once again if they were left ungrazed for a period? We do not know and perhaps it is not the key question. The answer is likely to differ from place to place. Rabbit grazing has stopped tree and shrub regeneration in some areas; it also exposes the soil to the occasional erosive rainstorms. Increased wildfire frequency does likewise. Physical trampling by increased numbers of domestic, feral and (some) native animals has also destroyed soil structure, increasing erodibility. Over very large areas there has been an erosion of the fertile few centimetres of topsoil, and this is likely to be a major barrier to revegetation. In the semi-arid woodlands of eastern Australia, loss of the original pastures has been followed by a steady increase of shrubs useless for stock. Fire is the best way to get rid of shrubs, but once shrub numbers pass a critical density, insufficient grass remains to carry a fire hot enough to destroy them. K.O. Campbell, as usual, puts the issues succinctly:
What we want to know is whether a new ecological balance can be established which will enable an economically viable cattle industry to persist indefinitely. If the answer is no, then perhaps we should withdraw these lands from pastoral occupation and concentrate on more suitable areas of the continent. Perhaps the answer will be conditional---a viable industry is possible provided institutional changes are initiated such as enlargement of holdings and the redistribution of land. Still another very real possibility that must be faced is that the lands of Central Australia can only be economically used for pastoral purposes as a slow mining proposition.
Large lightly stocked properties are probably the only way in which short-term economic survival and long-term carrying capacity can both be ensured in the rangelands. Without these prerequisites, eventual degradation due to overgrazing is likely, given the cautious rate at which most graziers destock going into a drought. While land administrators have the power to regulate grazing intensity on any area of land, Australia has yet to find a truly successful way of preventing overstocking. Recommendations for a 43% reduction in sheep numbers in the Gascoyne (WA) catchment in 1972 raised a political storm. A social technology which has implementation difficulties, but which could be worth thinking through would be to purchase grazing rights on pastoral properties, effectively setting ceiling stocking rates and thus encouraging amalgamation. A cheaper alternative, but one with political difficulties, is to impose stocking rate ceilings as lease covenants. Because of the social benefits of retaining the rangelands pastoral industry, there is a strong case to be made for social technologies such as tax averaging, which allow some smoothing of pastoral incomes from year to year.
Questions of social policy. Policy debate on appropriate future directions for Australia's pastoral zone will increasingly focus on social equity and quality of life issues. There are three major questions: Who shall provide basic services and under what conditions? To what extent should locational disadvantage be overcome by public intervention? To what extent should government endeavour to rationalise service provision by encouraging a restructuring of land use and settlement in remote areas?
Twentieth-century technologies (air transport, radio, satellites etc.) have enormously improved the quality of life in the rangelands, but it is still extremely expensive to provide basic communications, transport, health and educational services to the few people scattered through the bulk of the rangelands, meaning those areas inland from the Ecumene fringe and away from the handful of major urban centres (Darwin, Alice Springs, Broken Hill, Mt Isa, Kalgoorlie). Government continues to play the main role in providing these, commonly at subsidised or cross-subsidised prices. On efficiency grounds, there would appear to be a case to be made for withdrawing this support in, at least, areas with particularly poor viability prospects.
This could, however, eliminate pastoralism from
sizeable areas (e.g. Cape York, the Kimberleys, Gulf country) and, given the
difficulty of re-establishing settlement, any such action would need to be
evaluated very carefully. There are consider
able social benefits in having a cover of people, no matter how sparse, across the rangelands. They demonstrate to the world that most of Australia has low potential for human occupation. Being highly self-reliant, such people might (or already do) act as nuclei for a range of operations including search and rescue, defence operations, surveillance and reconnaissance, weather recording etc. They could act as rangers or wardens for the protection of natural resources in various ways, e.g. controlling feral animals. They would of course have to be paid, and pastoralism might have to play a secondary, or even negligible, role in their activities. As the basis for a new social technology, the idea is not greatly different, in principle, from European ideas of paying farmers to farm in traditional ways rather than profit-maximising ways in order to protect landscape and wildlife values.
The arid zone is arbitrarily defined as those parts receiving less than 250 mm or 10 inches of rain a year in the south, 350--380 mm in the north.
The arid (and semi-arid) regions of Australia usually have only 10--70 rain days per annum occurring in 3--24 clusters of rainy days. Generally no more than 5--8 such clusters, and sometimes only one, are large enough to affect the life cycles of the region's plants and animals. Further, rainfall is spatially variable, occurring often in patches of only a few sq km. The flora and fauna of the arid zone have been well reviewed by Owen Williams and John Calaby. Reptiles and ants are particularly well represented.
Five deserts and some mountains
It is place names which conjure up the arid zone. Gibson, Great Victoria, Great Sandy, Simpson and Sturt: the arid zone's five major deserts occupy 20% of the country. Three mountain ranges, the Flinders, the Kimberleys and the Hamersleys, flank the country's arid margins, and in the centre there is another group:MacDonnells,Olgas,Musgrave and Petermann. It is these harsh mountain ranges which provide the physical basis for the booming tourist industry.
Central Australia is too well vegetated to conform to the common concept of a desert, but the visual dominance of stony slopes and rock faces creates an impression of remarkable barrenness. The scarcity of meteorological stations makes it difficult to determine whether the ranges have moderating effects on the harsh climate, but stations above the 500 m contour enjoy about 50 mm more rain a year and lower temperatures than the adjacent sand plains.
Rainfall gradients and complex geology combine to form a great diversity of mountain habitats. These habitats, in particular the sheltered gorges and waterholes, harbour species of plants and animals which are relics of former high-rainfall periods or are outliers of species that normally live in higher-rainfall areas. Examples of large relic plants are the palm, Livistona mariae and the cycad, Macrozamia macdonnellii.
Competition for resources
Pasture ecologist Owen Williams once remarked that the whole of the central Australian cattle industry has about the same turnoff (deliveries to market) as a couple of good properties south of Dubbo. Ray Perry once observed that it cost CSIRO more to survey the Alice Springs region's resources than the land was worth. I have not gone back to check either figures, but the drift is right. Although the industry is hardly worth worrying about in production terms, it plays and will continue to play a key role in land-use--land-management debates, along with the other activities competing for a foothold in central Australia---tourism, Aboriginal lands, conservation, mining and recreation (including wilderness experiences).
The pastoral industry controls the bulk of the land in the central ranges. Most is too rugged to be managed economically; over large areas feral animals, notably horses, are completely uncontrolled and vegetation is unmanaged. The tourist industry wants access to this resource, but has no say in its management and is forced to focus on a few small reserves, all subject to rapidly growing tourist pressures.
There are numerous features in the MacDonnells and other ranges which could be included in tourist circuits. The Northern Territory Conservation Commission is planning a major park in the MacDonnells and this will be the trigger for a surge in visitor numbers. Great care will be needed to do this in a way that protects conservation values.
Recently, the prospect of reopening and
commercialising the Woomera rocket range in northern South Australia has been
raised. The Pitjantjatjara people are
not very impressed with the idea. The
defence establishment has long-term needs for sites
for facilities such as `over the horizon' radar stations. Rocket ranges and radar sites need big empty buffer zones and could in fact be very useful additions to the informal conservation reserve system.
Near Alice Springs there are substantial groundwater resources below largeish patches of soils suitable for horticulture. Transport costs are the main barrier to supplying out-of-season fruit and vegetables to coastal cities. Large groundwater reserves also raise the longer-term possibility of `sunbelt' urbanisation in the style of the American south-west. In summer, the central Australian arid zone experiences some of Australia's highest heat-stress values, but winter is very pleasant.
The point to be made is that there is a clear need to plan central Australian land use and not leave development and conservation of the region to a series of ad hoc `first come, first served' decisions. It is my belief that if this were seriously attempted, it would still be possible to accommodate most interests reasonably well. The sort of thing which goes wrong with piecemeal decisionmaking is that if two areas are equally suitable for use A, no attempt is made to develop the one which is likely to be less valuable for some prospective use B.
The North is sometimes thought of as everything north of the Tropic of Capricorn or north of 26°south, but it is more illuminating to think of it as three subregions---the Cape (Cape York and the Gulf Country), the Top End (of the Northern Territory including Arnhem Land and the Barkly Tableland) and the Kimberleys, the mountains of northern Western Australia. Life in all three is dominated by the profoundly seasonal wet-dry climate. In the future, life in all three will be increasingly shaped by proximity to Asia.
Since the beginning of non-Aboriginal settlement, northern Australian development has been firmly based on the commercial exploitation of natural resources---minerals, water, soils, vegetation and fauna. As is still the case, lack of industrial, urban and social infrastructure has been a serious impediment to development. Aboriginal lands and low-intensity pastoralism are the main extensive land uses, with pockets of mining, urbanisation, tourism and national park.
John Holmes describes the northern cattle industry thus:
These are Australia's most inferior pasture lands, with their extremely low nutritional value in the dry season enforcing a grazing regime characterised by uniquely low stocking densities, usually below two beasts per square kilometre. Cattle are of poor quality suffering annual nutritional stress, poor weight gain, high mortality and calving rates commonly below 40%.
Areas which can only be classified as inferior breeding country include north Kimberley, Top End, Northern Territory Gulf Country and Cape York proper. Nevertheless, the continuing replacement of British breeds of cattle with Brahman- and Africander-based breeds has the potential to lift productivity dramatically in the northern beef industry.
Clearly though, the role of lead sector in the development of the North has passed from agriculture to mining, with tourism not far behind. Using a relaxed definition of northern Australia which includes the Pilbara and the Bowen Basin, the region now yields a substantial proportion of Australia's mineral exports and contains a high proportion of all currently planned mineral developments. Similarly, two of the major foci of the tourist industry, Kakadu and the Great Barrier Reef, are in the North, as are future foci such as Cape York and
Like minerals, much tourism is an `export' and this sparsely populated triplet of regions already plays a critical role in maintaining Australia's economic health. There is every reason to expect that this role will become increasingly and proportionately more important.
That is not all. The North is vitally important for three other reasons: defence, quarantine and conservation.
The yearly alternation between wet and dry seasons helps in promoting habitat diversity and thus species diversity. Dick Schodde has produced figures which confirm that Cape York has the richest higher-vertebrate fauna in Australia and that the Kimberleys and Arnhem land in the Top End are not far behind (Table 4.6). The Cape York flora (2533 recorded species) is similarly richer than the Kimberleys flora (1673 species).
Region Amphibia Reptiles Birds Mammals
Cape York Peninsula 49 176 380 97
Arnhem land 29 133 287 59
Kimberley 33 156 269 56
Central east coast
and ranges 58 153 374 76
and ranges 43 79 342 66
South-west Australia 24 109 255 48
Australia 179 600 710 246
The main resource-based activity on Cape York is cattle grazing on large properties around Weipa and the Mitchell River to the south. Despite the fact that graziers in the northern parts face difficult mustering conditions and an uneconomical 600 km trip to Cairns to market stock, pastoralism remains the main activity over much of the Cape. Down the western side of the Cape, and south of the Iron Range National Park on the east, there are extensive Aboriginal lands with sizeable communities at Weipa,Aurukun, Lockart River and Bamaga. These communities are among the few still in a semi-tribal state and, as such, vulnerable to cultural dislocation.
Natural-resource-based activities in addition to `cattle hunting' include
* Mining. Comalco's bauxite mine at Weipa sits on one of the largest bauxite deposits in the world, with the mineral lying so close to the surface that extraction is cheap and the venture profitable. The only other current mining activity in the Cape York region is an offshore gold mine on Horn Island.
* Fishing. The main target fish in the numerous estuaries of Cape York region is barramundi, caught by about 100 licensed gill-net fishermen. Barramundi fishing is also an important tourist drawcard and is increasingly being promoted as such. The western Cape waters also support a large fraction of the northern prawn fishery; mackerel and mudcrabs are being increasingly sought.
* National parks. The region is recognised as a wilderness area of worldwide importance and contains eight national parks totalling 13 500 sq km north of Cooktown. Conservation groups such as the Australian Conservation Foundation and the Wildlife Preservation Society of Queensland continue to solicit support for declaration of further national parks (and wilderness areas) in the region. Declaration of the whole Peninsula region as a World Heritage Area has also been proposed.
* Tourism. Access to parks is primarily by four-wheel-drive vehicles in the dry season. There are about 15 tour operators and visitor numbers are proving a problem for limited numbers of park staff. The almost total lack of infrastructure only serves to increase the Cape's appeal as a `frontier region'. Most tourists drive from Cooktown to Bamaga on the tip of the Cape, but some fly directly in to Bamaga where there are several large tourist lodges.
Tourism, spaceports and planning. Tourism is a relatively undeveloped industry at the present time, but is expanding and has the potential for rapid growth in the future. It also has the potential to be very destructive, of both Aboriginal communities and the natural environment. Several proposals for coastal tourist resorts have been rumoured, but there is still no management plan for the orderly and conservative development of the region. The Australian Conservation Foundation drafted a land-use plan for the Cape as long ago as 1979; the Wildlife Preservation Society is doing the same thing a decade later. The Labor Government elected in Queensland in 1989 has however stated its intention of undertaking a land-use study of Cape York in collaboration with the Federal Government.
Cattle leases are being sold throughout the Cape at prices unrelated to their grazing potential. A number of these are in the process of being freeholded, with the prospect of very large capital gains because of their potential for tourist resorts. The way in which decisions to permit freeholding were being taken led to the Cape being dubbed the `last great honeypot for National Party supporters'. This is not quite fair. Since 1958 Queensland has allowed developed grazing land to be alienated to freehold over a period of 40 years. It does however show clearly how freehold tenure can cause land-management problems.
Tourism is not the only loose cannon around. Agricultural development for instance would
be likely to threaten the Great Barrier Reef by changing river runoff (coral is
sensitive to salinity and sediment concentrations) and delivering fertilisers
and pesticides into the sea. All forms
increase the risk of outbreaks of exotic disease (see Chapter 7).
The need for such a land-use-planning exercise is greatly increased by the prospect of a commercial spaceport being built on the Cape. The Cape, north of Weipa, is well located to launch satellites cheaply (some 20% greater payload than from Cape Kennedy) and reliably into equatorial orbit. Construction of the proposed spaceport would also require the construction of a small town and an all-weather road from the south and almost certainly would generate a tourist boom. The site favoured at present, Temple Bay, is particularly valuable for conservation and vulnerable to development. In terms of what is there now, a spaceport represents a massive social (e.g. Aboriginal communities) and physical (e.g. roads, acid exhaust gases from rockets) impact on the Cape. Now is the time, the only time, to think carefully and synoptically about the economic and environmental future of the Cape.
An exciting, but politically improbable way of managing Cape York Peninsula would be to bring it under the control of a new Great Barrier Reef and Cape York Park Authority. The Cape and the Reef are closely linked, ecologically and economically. The existing Marine Park Authority has demonstrated that it is possible to manage a great natural resource with respect for both utilisation and conservation interests.
The population of northern Australia is concentrated in the Northern Territory, particularly Darwin (70 000 people and falling) and Alice Springs (22 000 people). Because of a build-up in defence personnel, another 10 000 people will arrive in Darwin by 1995. The rate of population growth in the Territory was about four per cent per annum till recently, but has fallen sharply.
The primary production future of the Top End remains mixed:
* Broadacre dryland cropping (maize and sorghum) is still far from profitable and, in any case, would be limited to about 800 sq km in the Daly Basin.
* Commercial forestry faces a number of problems including cyclones, termites and woody weeds.
* On the other hand, the (small) buffalo industry has considerable scope for expansion in several markets: tourism, game meat, live-animal exports and pet meat. There is both potential and need for major genetic improvement in buffalo stock.
* The local fishing industry, based on barramundi in the estuaries and prawns in the Gulf, is growing rapidly at present. Under a bilateral agreement 135 Taiwanese pelagic fishing vessels operate in offshore northern waters.
* The environment (soils and climate) is very suitable for cashew nuts; world demand is extremely high and there is considerable genetic potential for increasing yields. Plantations are being developed at Adelaide River and on Melville Island. Lesser opportunities exist for other tree crops. Vegetables and flowers for Asian markets grow well and are being produced in slowly increasing quantities.
The outstanding physiographic feature of the Top End is the treeless, sedge-dominated coastal floodplains. A major rice-growing experiment in the 1960s at Humpty Doo near Darwin failed to demonstrate that these floodplains, comparable with those supporting enormous populations in southern China, could be intensively farmed with technologies then available. Half a million Magpie Geese helped Territory Rice Ltd reach this conclusion. The prickly weed Mimosa pigra is emerging as a major problem on these plains. With 300 sq km of dense to isolated plants at Adelaide River, the area has, in effect, been abandoned and the tourist development there is threatened. The problem is not yet as bad elsewhere.
Tourism. Tourism in the Northern Territory is predominantly park-based. The Northern Territory Tourist Commission is
actively adding new tourist destinations to the major attractions of the
national parks at Kakadu, Uluru and Katherine Gorge. The strategy seems to be to create a widely
dispersed set of `attractions'. Recent
additions to the tourist circuit include Gove, Cobourg Peninsula and national
parks at King's Canyon, Finke Gorge and Keep River. There are even plans afoot for the tiny
settlement of Borroloola on the Gulf. It
important to relieve pressure on Kakadu and Uluru, but this is far from the planners' minds. Rather, their complaint is that the Australian National Parks and Wildlife Service has managed Uluru and Kakadu too conservatively in terms of coping with booming visitor numbers.
Planners in the Conservation Commission have a better appreciation than those in the Tourist Commission of the need to `(i) conserve representative samples of major ecosystems; (ii) cater for current or projected recreation demands without compromising the visitor experience and threatening existing conservation values'. To this end, the Conservation Commission has established a register of sites of recreation and conservation significance to guide their land acquisition and management programs.
Minerals. The mining industry has dominated other sectors of the Northern Territory economy (tourism, livestock, fishing) since the mid-1960s. The place is extremely rich in minerals . For example:
* Prospects for further major discoveries of oil (and gas) in the Timor sea, 300 km offshore, are excellent.
* About 13% of the world's uranium occurs at the Ranger, Nabarlek, Jabiluka and Koongarra sites in Arnhem land and other potential sources in the South Alligator Valley. Along with royalty rates and land rights, uranium mining has been a highly controversial issue in the history of mining development in the Territory.
* The world's largest lead-zinc deposit (190 000 million tonnes) is located at McArthur River.
* One of the world's largest high-grade manganese mines is located on Groote Eylandt.
* The Gove Peninsula supports a major bauxite operation.
Despite an area of 422 000 sq km, the Kimberleys support only about 15 000 permanent residents, mainly in the towns of Broome, Derby, Fitzroy Crossing, Halls Creek, Kununurra and Wyndham. This population would be higher if a 1940s proposal to establish a 70 000-strong Jewish settlement in the East Kimberleys had received Federal rather than just State approval. The then-Minister for Immigration, H.V. Evatt, refused to consider the proposal on the grounds that Australia encouraged only individual migration, not mass migration.
The natural division of the region is into the East Kimberley based on the Ord River in the Carr Boyd Range, the West Kimberley based on the Fitzroy River plus the semi-desert plains to the south, and the North Kimberley bounded inaccessibly by the King Leopold Range to the south and the Durack and other ranges to the east. The Kimberley Plateau, which rises to 800 m and covers 130 000 sq km, is the dominant feature of the region. Despite the extreme tidal range, large deepwater ports could be developed on Bonaparte Gulf if warranted.
Agriculture. The Kimberleys are either too dry, too steep or too stony for dryland cropping, but do contain good dam sites and sizeable areas of irrigable soils on the mighty Ord and Fitzroy Rivers. As is well known, the Ord River irrigation scheme has not proved commercially successful to date. About 700 sq km are suitable for irrigation from Lake Argyle, but the actual area irrigated has never risen above 60 sq km. Transport costs and insect pests have ensured this. Further south, along the lower Gascoyne River, good soils, a satisfactory water supply and the Perth market 1000 km away have combined to permit the growing of vegetables and subtropical fruits. It is not difficult to foresee Kimberleys irrigation farmers meeting the fresh-food requirements of the Pilbara and Darwin in a short time. Large-scale rice growing at Camballin on the Fitzroy River failed in the 1950s.
The cattle industry depends on small areas of productive river-frontage country, much of which has been badly eroded. While most of the Kimberleys are held under pastoral lease, the area contributes little to Australian pastoral production. A substantial proportion of holdings are probably not potentially viable and should either be consolidated or, in the interests of soil conservation, removed from pastoral production.
Conversely, local optimists see a rosy future for the Kimberley beef industry, based either on shipping young stock south to be finished or finishing them on Leucaena pastures grown on the Ord irrigation scheme.
Minerals. The Kimberleys contain many regions with high mineral potential and
there is at present extensive exploration activity for a wide range of
minerals. The lack of infrastructure means that
only very rich deposits are likely to be developed in the short term.
There are huge bauxite reserves on the species-rich Mitchell plateau, but little short-term prospect of these being developed given the plethora of alternatives. Oil has been found around Barrow Island, but is insignificant compared with the natural-gas fields of the North-west Shelf.
The discovery of a large diamond province south of Lake Argyle has resulted in the region's first major mine. With a production of 35 million carats a year, this is the world's largest diamond mine---by volume, not value. It has also triggered very extensive diamond exploration over a wide range of rock types.
Tourism. The Kimberleys have the potential to become a major tourist area based on coastal resorts and inland features such as the brittle sandstone towers of the Bungle Bungle Range. Today, the industry is in its infancy. Developments have been initiated or planned for Walcott Inlet, Bungle Bungle Range and the Berkeley wilderness north-west of Wyndham. All have been criticised by conservation interests as being insensitively sited. Decisions on siting of the future road network are central to defining opportunities and constraints on the evolution of the tourism, wilderness, conservation pattern.
Wilderness and conservation. About 3.5% of the Kimberley region, some 14 800 sq km, is reserved as national parks or nature reserves. Existing reserves include both small special features such as Geikie Gorge and large reserves such as Prince Regent River and Drysdale River. In the 1970s, a government committee recommended the creation of 12 on-shore reserves and 18 island reserves. The adequacy of the reserve system is being reviewed again by the Western Australian Government. Surveys of plant and animal distributions are badly needed. The potential for world-class wilderness areas is considerable. In addition to the recently declared Purnululu (Bungle Bungle) National Park, areas which have been identified as having reserve potential include
* Mitchell Plateau;
* Walcott Inlet;
* Edgar Ranges;
* Roebuck Bay and Eighty Mile Beach (one of the most important roosting sites in the world for migratory birds);
* King Leopold Range;
* Oscar, Napier and Geikie Ranges;
* Rowley shoals.
The future of Kimberley rainforests is a major issue. There are over 500 patches of rainforest in the Kimberleys, the largest being about 100 ha. Because they are remnants of an earlier age, they have high conservation value. Unfortunately, many are proving vulnerable to an increasing number of manmade wildfires in the region.
The Kimberleys are somewhat behind the Top End and Cape York in the development stakes. There is not quite the same urgency about controlling haphazard development, but the breathing space can only be several years. It is not particularly bold to predict that the Kimberleys will be the next major environmental battleground after Cape York. The medium-term key to managing the region, including its defence role, will be the coverage and quality of the road network.
Defence and coastal surveillance
Defence against what? Australia is, in fact, a remarkably difficult target to attack. It is remote from the major centres of global power and surrounded by seas of oceanic proportions on three sides. The factors that made the early colonists feel isolated and vulnerable are now extremely valuable defence assets. Several relevant countries possess large armies, but practically none has the vast numbers of ships and aircraft that would be needed to transport a substantial military force across the sea-air gap that surrounds Australia.
Nonetheless, Australia's defence planners concluded
in the early 1970s that we had to provide for our own defence at a far higher
level than before. As a consequence,
northern Australia is becoming a far more important location for defence
operations, for exercises and also for basing defence units. The speed and scope of both civil and
military infrastructure development across northern Australia has been dramatic
in recent years, especially in the Northern Territory. The pace is also quickening in northern
Queensland. Developments include Royal
Australian Air Force airfields at Katherine and Weipa, surveillance units in
the Pilbara, Kimberleys and north Queensland and, eventually, an Army brigade
at Darwin. While of suspect commercial
value, the defence value of an Alice Springs--Darwin rail link is substantial
and were it to eventuate there would be very strong civil-military grounds
for a further standard-gauge connection across to Queensland. For example, such a line would facilitate the opening of an envisaged $250 million manufacturing development at Phosphate Hill near Mt Isa. The fact that a facility might be useful is not of course an argument that it should be built; that depends on the opportunity cost of foregone projects.
Australia is more susceptible than most countries to the watery threat of mine warfare;; by volume 99.9%, and by value 82% (over $33 bn a year) of Australia's export trade goes exportsby sea. In 1940 a single German mine layer dropped 230 mines off the eastern seaboard, caused millions of dollars of damage and disrupted Australian shipping for months. At least 16 vessels, over 18 000 tonnes of shipping, were sunk.
Australia's vulnerability to mines has, if anything, increased since then. The bulk of domestic and interstate trade is shipped from just a handful of ports including Port Hedland, Barrow Island, Port Kembla, Sydney, Newcastle and Mackay. Mines are an ideal weapon for terrorists or countries wishing to make a point anonymously or in a way that will not automatically result in escalation. Mines have become much harder to detect, increasing the disproportionate response required to sweep or hunt them. Australia needs and is slowly acquiring offshore mine-clearing capability.
Other potentially vulnerable important infrastructure in northern Australia includes the North-West Shelf gas fields and, if they get built, the Dampier--Moomba gas pipeline and the Darwin--Alice Springs railway. Meanwhile, it is the quality of the northern road network which is the focus for much defence thinking.
In far north Queensland the progressive improvement of the Peninsula Development Road from Lakeland to Weipa high up on the west coast of Cape York Peninsula has great significance for the defence of the region as well as for regional development. However, until such time as this road is improved to all-weather standards and is extended to Bamaga on the tip of Cape York, the Peninsula will persist as a strategic vulnerability of very significant proportions. The extent of the isolation of Cape York Peninsula, that is north of the Jardine River, and the emptiness of the Cape itself south of the Jardine is extraordinary. This, combined with the unimpeded `porosity' of the Torres Strait Islands ... constitutes a serious and exceptional vulnerability in security terms generally---to illegal immigration; to fisheries, customs and quarantine violations; and to all manner of perceptions of low-level defence contingencies.
The more general point behind this quotation is that there is considerable interdependence between military and resource-management/development planning in northern Australia. Serious attention needs to be given to Jol Langtry's suggestion for a national organisation to co-ordinate defencenational security planning with regional and national development.
Defence is one dimension of northern coastal surveillance. The others are customs, immigration and quarantine, with the last being most relevant to a discussion of resource management. The current system of aerial littoral surveillance for quarantine purposes (`Coastwatch') has recently been judged ineffective in the Lindsay report. This committee recommended that a new program of agricultural agriculturequarantine measures (Northern Australia Quarantine Strategy) be developed based on enhanced monitoring, sampling and surveys for various plant and animal pests and diseases and their vectors in northern Australia and in neighbouring countries. There is a draft plan prepared for fighting an outbreak of exotic animal disease on Cape York, but it needs to be developed further and integrated with a modern information system and a research program for understanding the spread of diseasesexotic disease as well as any improved programsdisease surveillance program (see Chapter 7).
The Coastal Zone
Anthropocentrically speaking, the coastal zone provides sites for a wider range of uses and functions than any other part of the continent. These include residential and commercial use, recreational use, commercial fishing, ports (about 120 in all) and sea transport, waste disposal, tourism, conservation of natural environments and industrial uses such as cooling, salt production, pulp production, mining and agriculture.
Coastal zone management
Management of the much sought-after
coastal zone has traditionally been the responsibility of local government
(e.g. subdivision approvals) although various State government agencies have
usually assumed oversight roles for conservation, beach
protection etc. State government agencies have also undertaken most of the major coastal engineering works, often, until relatively recently, with little participation by local residents and users of the affected resources. Offshore, the Seas and Submerged Land Act 1973 (Cwlth) brought all land below the low-tide mark under Commonwealth control although the States, under subsequent agreement and coastal waters legislation, continue to control fisheries and other resources out to three nautical miles. Whether this will remain the case following a decision in November 1990 to extend Australia's territorial sea from three to 12 nautical miles offshore has not been decided.
The resources available for coastal-zone management in most coastal local government areas are pitifully small. Protection of shorelines, upkeep of recreation areas and repair of storm damage require costly programs for beach replenishment and dune maintenance. Local authorities tend to resist coastal protection schemes which potentially restrict rating bases and are particularly concerned about the extent to which local taxes provide benefits to non-resident visitors. In Queensland, a few local councils have refused development applications only to have their decisions overturned by the State Government.
The questions of central concern to coastal-management agencies are about allocation (which groups get access to which resources) and about operations---selecting ways of implementing and controlling allocated land uses. Important tools of present-day coastal management include land-use planning, policy statements, environmental impact assessment and the preparation of site management plans. Unfortunately, perception of the need for coastal-zone management has arisen only in the last 20 years or so and many historical mistakes remain---not to mention ongoing problems which remain unaddressed.
Pollution and waste disposal are widespread, although generally localised, issues in coastal-zone management. Examples include
* runoff of agricultural chemicals (e.g. of insecticides to the Great Barrier Reef)
* eutrophication following fertilisation from runoff nutrients. Algae grow so prolifically on the surface that they deprive the water below of oxygen and light, thereby killing most marine organisms (e.g. Gippsland Lakes, Peel Harvey estuary in WA)
* pulp mill effluents (e.g. at Lake Bonney, South Australia)
* sediment loads (e.g. silt from the Mt Lyell mine (Tas) has destroyed the ecosystems of Macquarie Harbour)
* offshore sewage disposal (e.g. Sydney, La Trobe Valley).
* heavy metal pollution (e.g. the Derwent estuary, Gove Peninsula)
* toxic algae (e.g. in Port Phillip Bay, Gippsland Lakes, Port Adelaide, Peel Harvey estuary (WA). These probably arrived originally in some of the 60 million tonnes of ballast seawater unloaded each year in Australian waters and destined no doubt to introduce further pests. The toxic effects run right up the food chain to humans.
* loss of fish nurseries. Seagrass beds, which are important fish-nursery areas, are being lost through various forms of pollution around Australia, e.g. eutrophication and heavy metals in Western Australia, sewage in South Australia, sedimentation in Victoria.
* overdevelopment of biologically important estuaries. Estuaries with high conservation value which are under threat from development include Burdekin River (Qld), Corner Inlet, Port Phillip and Westernport Bays, Gippsland Lakes (Vic), Port Adelaide River (SA), Tamar River (Tas), Tweed, Richmond, Hunter and Hawkesbury Rivers, Lake Macquarie, Port Jackson, Botany and Jervis Bays (NSW).
* oil spills. In 1968, the Merlin A7 oil well blew out in Bass Strait. In 1970 the tanker Oceanic Grandeur struck an uncharted rock in Torres Strait and Australia witnessed its first major oil spill.
* release of large quantities of stored water which are too hot (e.g. power plants), too cold (e.g. irrigation water from Dartmouth dam) or too low in oxygen (e.g. the Pieman River in Tasmania).
One of the fundamental
rules of good planning is that if you have a scarce resource or one which is
already performing useful functions, you do not waste it by using it for some
purpose which could be located elsewhere. Applying this in the coastal zone, land uses which
do not really require access to the water's edge should be set back from the
coast; high-rise buildings on the unstable foredunes of the Gold Coast are a
good example. A low-key example of the
same phenomenon is haphazard holiday shack development along large parts of the
South Australian coastline including Yorke Peninsula. Large stretches of the South Australian coastline have been made inaccessible to the public.
Other examples of bad misuse of the coastal zone include the destruction and draining of wetlands (often valuable fish nurseries) for urban developments, including canal estates in northern New South Wales and Queensland. Every State has its examples of poor coastal-zone management although it is Queensland which is the current laggard in acting on the need for improvement.
Mineral sands mining for heavy minerals such as rutile, zircon and ilmenite has been a major coastal-zone industry and likely to be so again (notwithstanding several inland discoveries, notably Horsham in Victoria). It is confined essentially to three sections of the coast:
* central New South Wales to Gladstone
* inland from Capel and Bunbury, south of Perth
* the east coast of King Island in Bass Strait.
The industry generates little pollution, but it cannot be pretended that the landscapes which are reconstructed nowadays following sand mining are anything like as ecologically rich as pre-mining landscapes. Some mineral-rich sandscapes such as those of Fraser Island probably have too high a conservation value ever to be mined. Equally, one can sympathise with sand-miners who see valuable deposits lost forever under residential developments and freeways. Mining in advance of such developments would be sensible.
Irrespective of the degree of CO2-induced climatic change pending, the Australian coastal zone will undoubtedly continue to undergo major anthropogenic and, to a lesser extent, non-anthropogenic changes. As the primary example of `natural' change, the widespread beach erosion experienced in recent decades will probably continue; there will still be localised areas of coastline build-up of course, including areas where sediment from accelerating upper-catchment erosion following deforestation is already being delivered. Many prime recreation beaches (e.g. Adelaide, Gold Coast) are already regularly replenished with trucked-in sand.
The need for co-ordinated management of the coastal zone is illustrated by the fact that erosion of Gold Coast beaches increased rapidly following the construction of retaining walls on the Tweed River which diverted the former longshore northern drift of sand. Unless effective controls can be developed, natural erosion will continue to be exacerbated by off-road recreational vehicles destroying dunes and beach ridges in many areas, e.g. the Coorong.
Sea fisheries are of three types: demersal, inshore and pelagic. Demersal fish are those living on the sea bottom of the continental slope, the ones normally caught by trawling, e.g. gemfish, blue grenadier, orange roughy. On the east coast almost all the known demersal resources are being utilised. Those of the south coast are not heavily utilised (much of the bottom is not trawlable) and those of the west coast up to Shark Bay unknown. It is the area of the North-west Shelf and beyond to the Gulf of Carpentaria that presents the most interesting possibilities. Several countries including Japan and the Soviet Union fish the area, but are taking probably less than half the estimated maximum sustainable yield of 90 000--150 000 tonnes per annum.
Inshore fish, crustaceans, and shellfish live along the coastline and in estuaries. The best-understood species are scallops, rock lobsters, prawns, oysters and abalone. Scallops and abalone have been overfished in recent years, but the rock lobster fishery, particularly in Western Australia, is widely regarded as well managed. Western Australian legislation aimed at maintaining the industry at a viable level includes regulations on minimum catchable size, lobster pots that allow smalls to escape and limits on total fishing effort. Annual lobster production in the West has now stabilised.
Pelagic fish are those permanently swimming in the
waters between sea-surface and seabed.
Our commercially harvested pelagic fish include bluefin tuna, skipjack
tuna and jack mackerel off south-eastern Australia and Australian salmon off
southern coastline beaches. Of these,
only bluefin tuna and Australian salmon are reasonably well
understood; exploratory fishing to inventory pelagic species is expensive. Considerable concern is being expressed that bluefin tuna stocks have already been badly overfished and severe restrictions on foreign fishing efforts are being enforced. Unfortunately, social technologies which could control fishing efforts by Australian boats have been proposed, but have not been developed and introduced.
Prawns Lobster Abalone Scallops Oysters Fish
22.0 14.5 6.4 16.4 8.3 57.1
21.7 15.0 5.5 5.0 8.2 110.0
(190) (193) (90) (12) (47) (185)
Many marine species that are distributed throughout parts of south-east Asia and the Pacific also occur in Australia. Some of these have been overexploited outside Australian waters and Australia offers the best chance for their long term conservation. Examples are mangrove species, marine turtles, dugong, saltwater crocodiles and trochus shell. Australia has hundreds of mostly small marine reserves, most of which are attempts to protect commercial fishing activities. Queensland and Western Australia are most advanced in actively developing a system of marine and estuarine protected areas. New South Wales is the most backward because of bureaucratic in-fighting for control of such reserves.
Inescapably, the dominating force for
change in coastal Australia into the next century must be that of increasing
population. Most of the 11--15 million
extra Australians we can expect by then will be found in and around the
existing major metropolitan and provincial centres, i.e. like 85% of the
population, they will be living in or close to the coastal zone. Table 4.8 and Map 4.5 illustrate (a) local and (b) regional population pressures on different parts of the Australian coastline. Map 4.5 shows numbers of people living within half a day's drive of different parts of the coast in 1981 and Table 4.8 gives changes since 1971 in the number of people living within three km of the coast.
1971 1986 71:86 %Chnge
D Arnhem Land
-C.York 9 602 13 047 3 445 35.9
C9 Cooktown 401 308 -93 -23.2
-Cairns 59 841 95 406 35 565 59.4
C3 Bowen-Mackay 33 177 48 095 14 918 45.0
-Maryb'ough 44 546 73 538 28 992 65.1
G&S Coasts 234 631 400 914 166 283 70.9
North Coast 63 929 140 779 76 850 120.2
A2 Newsydneygong 1402 311 1515 294 112 983 8.1
South Coast 15 206 42 352 27 146 178.5
-Far Sth NSW 7 561 14 939 7 378 97.6
B6 Tasmania 249 296 296 793 47 497 19.1
B9 West Gippsland 5 686 9 543 3 857 67.8
-Geelong 568 046 632 488 64 442 11.3
Victoria 35 437 42 920 7 483 21.1
C8 South East SA 2 902 3 736 834 28.7
Environs 39 834 37 317 -2 517 -6.3
A4 Adelaide 171 040 207 834 36 794 21.5
C7 Eyre Peninsula 2 521 3 734 1 213 48.1
Australian Bt. 3 300 4 175 875 26.5
-Esperance 20 618 26 941 6 323 30.7
B3 Perth Environs 24 104 39 555 15 451 64.1
A5 Perth 325 163 373 617 48 454 14.9
C2 Geraldton 17 586 23 619 6 033 34.3
D Shark Bay
-Exmouth G. 4 974 6 764 1 790 36.0
C4 Port Hedland 12 948 13 623 675 5.2
D Broome-Wyndham 8 629 14 376 5 747 66.6
C1 Darwin 32 149 42 116 9 967 31.0
Australia 3395 438 4123 823 728 385 21.5
of Australia 9360 400 11478 333 2117 933 22.6
Australia 12755838 15602156 2846318 22.3
Given the Australian penchant for coastal recreation and increasing real incomes, it is a most reasonable scenario to foresee the coastal zone from Cairns to Adelaide continuing to be our main setting for resource and environmental conflict, competition and controversy. Rising demands for accessible sites near population centres for both productive and consumptive uses will have to be met from a fixed land supply. Unfortunately, coastal resources are what are known to economists as positional goods i.e. available only in fixed quantity; as population increases, average coastal resources per person decrease. In practice, positional goods in our society are largely rationed by price. For example, it is psychologically very important to be free to hike right around the rim of the country, but up-market coastal-resort developments are already threatening the accessibility of a number of areas for the hoi polloi.
The pervasive coastal issue for many years then is likely to be the impact of interest-group demands and their associated externalities on a resource which is scarce and essentially fragile in its scenery, landforms, waterbodies and vegetation. Coastal-degradation issues most frequently foreseen in the 1979 CSIRO survey were concerned with questions of despoliation from open-cut, strip and sand mines, coastal erosion and instability, and pollution.
Succinctly then, for most people, the likeliest coastal scenario is one of declining access to a degrading resource. However, at the risk of being over-optimistic, the emergence of techniques for the management of development, such as participatory land-use planning stand to increase the legitimacy (public acceptance) of an increasing number of resource-allocation and management decisions. Four Australian States (Victoria, Queensland, South Australia and New South Wales) have enacted legislation specifically for coastal-zone management in response to coastal erosion, to coastal land-use conflicts and to improve co-ordination between the numerous State agencies interested in the coastal zone. Federally, it is Labor party policy to establish a National Coastal Management Working Group to develop, under the auspices of the Minister, a National Coastal Management Policy.
Impact of climatic change
Current predictions of climatic change in coastal Australia over coming decades include sea-level rises of 20 to 140 cm and increased storminess, including cyclones penetrating further south than at present. In fact, the most recent scenario from CSIRO Division of Atmospheric Research (August 1989) reduces the predicted sea-level rise to a mere 20--30 cm.
Of all parts of Australia, the coastal zone is likely to be particularly affected by climatic change because, in addition to these direct effects, the coast would experience a range of effects derived from changes to vegetation, runoff and land use in non-coastal catchment areas (Box 4.1).
As ocean volumes swell with increasing temperatures, sea levels will rise. The physical consequences of sea-level rise per se can be broadly classified into three categories: shoreline retreat, temporary flooding, and saltwater intrusion. Effects on natural (unmanaged) systems are difficult to predict, but at this stage it can be guessed that rates of change, particularly on rocky and tidal-flat coasts, will be low enough to permit smooth rather than abrupt transitions to new states, e.g.
* intertidal mangrove and shorebird habitats building up in synchrony with sea-level change
* upstream penetration by salt-tolerant species
* gradual inundation of existing (unmanaged) wetlands on low-energy coasts (i.e. where the continental shelf is wide), matched perhaps by the creation of new wetlands further inland.
In addition to shoreline
retreat due to higher sea levels per se, erosion of beached coastlines (the
foci of coastal recreation) can occur at catastrophic rates under the impact of
a single storm, given suitable preconditions.
A small increase in the frequency of extreme storm events (as predicted)
is thus, potentially, a
contingency which could massively exacerbate coastal erosion.
Highlighting the importance of getting a smooth adjustment of the ecosystems on tidal flat coasts is the fact that about two-thirds of Australia's east-coast commercial fish catch is composed of species that depend on mangrove estuarine areas. Probably little can be done to modify the way most physical and biological systems will evolve together and even if it could, agreement on what to do would be difficult to reach.
One legacy of Australia's 19th-century dependence on sea transport is that many coastal settlements are situated at the navigational limits of rivers and are particularly vulnerable to flooding. Increased rainfall, increased storminess and drainage systems backed up longer because of reduced heads (fall to the sea) will increase the frequency, but not really the nature of flooding in east-coast settlements.
Saltwater intrusion via both breached barrier formations (e.g. the lower Murray in South Australia) and higher sea levels per se (e.g. Kooweerup Swamp on Westernport Bay, Victoria) will affect water supplies to coastal agriculture in a limited number of locations. In the Burdekin delta in north Queensland saltwater intrusion into groundwater is already a problem and this may intensify. Perth and Newcastle are the only large coastal centres dependent on groundwater, but they are unlikely to be affected in this way.
Ultimately, changes in lifestyle for most
Australians as a result of coastal-zone changes are likely
to be more those of degree than of kind. It is commonly the poor who suffer most under the impact of change, whatever form it takes. In this context, coast dwellers in Australia are, if anything, better off than their non-coastal counterparts. The smaller coastal towns, dependent on State largesse and with undeveloped rate bases, are least likely to be able to take defensive action against increased erosion and flooding. Coastal-resort towns, existing largely for their beach recreation and/or seaside holiday opportunities, will be under special threat.
In a recent conference paper on the implications of the Greenhouse effect for coastal Australia, colleagues and I came to the following conclusions:
1. With the exception of increased flooding in coastal settlements, the impact of marine-mediated climatic change by 2030 on settled areas of coastal Australia will be small. Impacts on coastal agriculture are most likely to be via highly localised saltwater intrusion into (a) rivers and (b) groundwaters used for stock watering and irrigation. Impacts on coastal recreation are most likely to be via the accelerated erosion of numbers of east- and west-coast sandy beaches.
2. Many of the adverse economic impacts of sea-level rise might be avoided if timely anticipatory actions were to be taken. As of now, design of new infrastructure should be based on the assumption of future higher sea levels, e.g airports, housing, marinas, septic tanks, sewerage systems, roads, bridges, power plants. There is an associated need for improved briefing of engineers, home builders etc. A need to cope with increased coastal flooding, taken together with the already dilapidated state of many urban drainage systems, can be viewed positively as creating an opportunity to redesign environmentally sound drainage infrastructure, e.g. use of grassed waterways for cleansing water.
3. Contemporary trends in all States towards improved coastal planning and management need to be encouraged, including that of increased recognition for the role to be played by local communities. One need is to follow land-management practices which are already recommended, but little implemented. Another is to develop and apply methods for large-scale impact assessment in priority areas of high population pressure, vulnerable infrastructure and increased hazard from erosion, cyclones/storms, inundation and flooding (Map 4.6). Such methods must particularly recognise a full range of impacts and their different effects on different groups of people.
4. Given the uncertainties inherent in the climatic-change issue, scientists, quite rightly, will wish to emphasise the need for more research, but at the same time they must resist the temptation to orchestrate fully this `tenuous melody'. Several scientists have already warned the scientific community against tunnel vision, groupthink and an unwillingness to recognise potentially positive effects of climatic change. Already there is a community scepticism about the rapid changes foreseen in scientists' far-off Greenhouse scenarios.
5. As an umbrella conclusion, the prospect of climatic change is best regarded as an inducement to begin taking a wide range of adaptive actions which, irrespective, we should already be taking.
The High Country
Islands in the clouds
Australia has very little high-altitude land. Apart from the Eastern Divide, the only country above 600 m is small parts of the Hamersley Range in the arid north-west and the MacDonnell Range in the centre (Map 2.2). At the base of Cape York, the Divide is only a series of low hills, but coming south it increases in height to over 2000 m at Mt Kosciusko before turning west and heading for the Grampians. To quote Cliff Ollier, the Great Dividing Range is a cartographic myth, crossing remarkably flat country for much of its length. The Great Escarpment to its east however is a major landform, thousands of kilometres long and often over 1000 m high. It forms the edge of the uplifted plateau from which the main alpine regions have been carved out as residual `islands'.
In the tropics, there are two high-country islands: the Atherton tableland behind Cairns and the Mount Windsor-Mount Carbine-Main Coast Range tablelands further north again, behind Daintree. They are also islands in the biogeographical sense of supporting rainforest ecosystems and species markedly different from those in surrounding areas. The Mount Windsor tableland contains magnificent and spectacular mountain scenery in a largely unlogged, undisturbed condition.
]The cold high country, meaning firstly the mainland alpine and subalpine areas lying above about 1300 m and receiving regular snowfalls, occurs in patches (islands) extending from Australian Capital Territory (360 sq km), through the Snowy Mountains (2600 sq km) into the Victorian Alps (2300 sq km). A recent proposal for a 16 400 sq km Australian Alps World Heritage area includes all of this. The central Tasmanian plateau contains most of our other cold high country (4900 sq km). In toto the cold high country occupies less than one per cent of Australia. Ours is the only continent without even one active glacier.
In the alpine zone, above 1830 m, snowgum woodlands of the subalpine zone (down to 1370 m) give way to treeless herbfields. High-yielding alpine ash forests occur up to 1500 m. Botanists such as John Turner, Alec Costin, Stella Carr and Dane Wimbush have carried out the long-term observations which allow us to understand the dynamics of high-country vegetation change reasonably well. The key to the fragility of high-country ecosystems is that plants grow slowly at low temperatures and hence take a long time to recover from any disturbance. Thus, at subalpine altitudes, routine burning to produce a `green pick' and grazing it, even at low stocking rates, turns grassland into eroding shrubland which, if protected, will eventually revert to grassland---provided enough soil remains. From a management point of view the message is that vegetation changes markedly when disturbed, but if left alone probably recovers after a very long time.
Roles and functions
Grazing and water catching
For 120 years or so the main role of the cold high country, in land-use terms, was in providing summer grazing for sheep and cattle. In the mid-1940s it was recognised that grazing had changed the alpine and subalpine vegetation so as to expose the soil to erosion. Kosciusko State Park was declared in 1944 in New South Wales and in 1946 graziers and soil conservation authorities agreed to limit grazing on the Bogong High Plains in Victoria.
At that time it was clearly recognised that the alpine areas fed the headwaters of a number of our most important rivers with snowmelt, including the Snowy River with its visionary possibilities for being turned inland for hydroelectricity generation and irrigation. The water-catchment function was to be regarded as pre-eminent. Water yields could be increased by, for example, using snow fences and plantations high in the catchments to trap more snow. Today this would conflict with trends to conserve the high country in as natural a condition as possible.
Despite the evidence that the relatively low numbers of summer-grazing cattle in the Victorian Alps are causing and have caused serious damage to plant, soil and water resources, the Victorian Government has been politically unable to accept the advice of the Department of Environment and Conservation and exclude cattle from its newly declared Alpine national park.
Skiing, fishing, hiking, horse trekking
While graziers are slowly losing their access to the high country, largely to protect water supplies, new debates are arising about how these areas are to be used. Today, the main commercial use of land above 2000 m is snow sports. Even this is a marginal undertaking since the length of the snow season (around 16 weeks) is short by world standards, meaning that the capital tied up in resort infrastructure has little time to earn its investors a return each year. Accentuating this, records for recent decades show that the length of the snow season has been getting shorter and that snow cover has been getting shallower. Greenhouse warming can only reinforce this trend and reduce the areal extent of the snowfields. In summer, the high country increasingly supports extensive recreation pursuits such as trout fishing, bushwalking and horse trekking. Conferences too.
These apparently innocuous activities can have serious effects on high-country ecosystems, at least when large numbers of people are involved. Clearing treed areas to enlarge ski slopes reduces catchment effectiveness in a number of ways (e.g trees collect water from mists) and raises the possibility of major erosion if done carelessly. The newest threat is all-terrain vehicles which turn tracks into ever-widening quagmires.
Building ski resorts above the snowline creates a
host of environmental problems and there is now a routine acceptance of the
need to bring skiers in from lower areas each day. Nonetheless, the Victorian Government is
currently considering consultants' proposals to double the bed capacity in the
upmarket Falls Creek resort. In general,
there appears to be little recognition in the Alpine Resorts Commission
(the body managing most Victorian ski resorts) of their statutory responsibility to provide snow sport facilities to the whole community, not just the rich.
The bogs and fens which maintain stream flow in dry periods and in winter when flow is especially needed for electricity generation are particularly susceptible to trampling, whether by cattle, horses or bushwalkers. An alpine bog invariably dries out permanently once a drainage line forms in it.
The high country offers a classic example of competition for and conflict over a limited natural resource. Even bushwalking and horse trekking can come into conflict, e.g. when bushwalkers on a popular trail start to resent bedding down on steaming horse dung. Overall though, the high country still seems manageable provided that its various uses can be kept to moderate levels. This is in fact the basis of much successful natural resource management; start actively managing the resource before it is buggered up and do not let any interest group's greed get out of hand.
In 1979--83, after years of public debate, the Victorian Land Conservation Council allocated 14 800 sq km of their high country to increase the area of parks plus other reserves plus the area of State forest to 49% of the total area at the expense of previously uncommitted land. The plan made provision for alpine resorts and for areas with grazing, water production and hydroelectricity generation as their prime functions. All in all it was an excellent example of thoughtful, deliberate and responsive land-use planning, albeit based on somewhat inadequate information. More is the pity that similar exercises are not being carried out in other high-demand areas such as the Top End, Cape York and, indeed, the high-altitude Tasmanian Central Plateau.
The outstanding resource of the Tasmanian Central Plateau is its water yield, and this has been almost fully harnessed for the generation of hydroelectricity. The major land-use activities include forestry, grazing, recreation and tourist uses. Fishing is excellent in the numerous lakes. Management of the region is complicated by the fact that 35% of the land is privately owned, with the rest being managed by various State agencies with fuzzy jurisdictions. Soil erosion due to burning off, grazing and, more recently, off-road vehicles, is severe above 900 m. Recent inclusion of much of the Plateau in a World Heritage Area may lead to its being more purposefully managed.
As noted earlier, only about 14--20% of Australia (depending on definitions) is wooded or forested, mainly in the better-watered parts of eastern, south-western and northern Australia. This is a lower proportion than many countries (e.g. Japan, New Zealand, Canada, Sweden), but still puts us well above the world average in terms of forest area per head of population.
Forests for timber
Australia's forests produce about 17 million cubic metres of wood a year divided into various products as follows:
Sawn timber and veneer 48%
Paper and paper products 17%
Wood-based panels 7%
The forest-products industry is an important component of the manufacturing sector. It has a diversified structure ranging from small logging and sawmilling operations to large vertically integrated paper-products manufacturers that are increasingly international in ownership and outlook.
While 1.06 million sq km of Australia is covered by forest or woodland, only 41% of this is regarded as capable of yielding timber for industry and nearly three-quarters of that is publicly owned---a third of the publicly owned forest being in State forests dedicated to timber production as the primary form of land use and 10% in conservation reserves. Since the second world war, the implicit `strategy' of the timber industry has been one of `running down' the stock of sawlogs in native forests to meet strong demands while simultaneously building up softwood stocks in the form of pine plantations.
Under present plans, probably more than half of all State forests will never be logged, but will be retained for catchment protection and other non-commercial purposes. In fact timber management is likely to be confined at most to about 10% of the potentially exploitable native forest.
For wood production, four broad categories of native forest are recognised:
* eucalypt forest (68% by area)
* rainforest (5% by area)
* cypress pine forest (11% by area)
* tropical eucalypt and paperbark forest (16% by area)
In their present condition, most Australian eucalypt forests have a very low capacity to yield sustainable high volumes of industrial wood, due to (a) the overmaturity of individual trees, with consequent low net growth of stemwood, and to (b) the low level of use relative to total wood yield. Because the removal of large and defective trees could not usually be justified economically, early forest-management practices were often too conservative to stimulate the growth of the forest as a whole (i.e. the amount of timber in an old forest stays constant from year to year). The yield of timber can be greatly increased however by appropriate silvicultural treatMent, silviculture being the science and art of growing and regenerating forests. These treatMents include clear-felling, short rotation times, stand thinning, fertilising and, in some cases, the use of pesticides. They can have dramatic effects on the appearance, composition and functions of forests.
Likewise the yield can be increased by raising the level of use through integrated sawlog and pulpwood operations. For example, sawmilling converts less than half gross log volume into sawn timber. By pulping logging residues in an integrated operation, total use is much greater. Such integrated harvesting requires careful supervision to minimise environmental impacts. The main argument against woodchipping is that there is insufficient knowledge about its long-term effects to ensure that irreversible degradation of the forest resource does not occur. There is a strong case for pausing with woodchip projects while the effects of existing operations are monitored.
Australia had about 36 000 sq km of rainforest of all types in 1788. The present area is under 20 000 sq km, nearly half having been diverted for agricultural, forestry, urban development and other purposes. Still remaining are
* 7000 sq km of tropical rainforests on the wet coast between Cooktown and Ingham
* 6000 sq km of subtropical rainforest between Ingham and northern New South Wales
* the temperate rainforests of southern New South Wales, Victoria and Tasmania.
Timber output from rainforests is now less than five per cent of the Australian total. It is used for specialities such as veneers, plywoods etc. and for general construction. Research into the production of specialty woods from plantations of both tropical (e.g. Queensland red cedar) and temperate (e.g. Tasmanian blackwood) rainforest species is in progress.
Other forest uses and functions
In presenting arguments for the dedication of Crown lands as State forests, forest services have traditionally stressed the role of forests in watershed protection, domestic and industrial water supply, and wood production, considering all three to be compatible. A significant share of forest land in the vicinity of Perth, Melbourne, Sydney and Brisbane is devoted to metropolitan water-supply catchment. The conservation of flora and fauna in undisturbed forest habitats has been catered for by setting aside flora and fauna reserves. Similarly, forest recreation parks and scenic reserves have been established.
Nevertheless, there has been strong criticism of the emphasis on wood production in Australian forest management. Such criticism stems in part from changing social values
* Urban water consumption is expected to increase three- or four-fold over the next century and forested catchments have an important role to play in regulating stream flow and maintaining water quality.
* Forest landscapes are an important resource of the tourist industry.
* Forests are major wildlife habitat areas which must be conserved if forest-dwelling species are to be preserved.
In the east-coast forests, the most fertile areas support the richest fauna, are the best for timber production and, when cleared, often make the best farmland. In the Eden woodchip forests, the fauna is concentrated in stands on the better-quality granite soils, the first to be felled.
Logging has an immediate effect on individual
animals: they lose their homes and feeding grounds and die. Then there is, at least, a temporary effect
on the range and abundance of species, particularly tree-dwellers. Locally, some species will perma
nently disappear, perhaps go extinct. The known distribution of the now extinct Tasmanian Tiger coincides with what were once among the most fertile forested areas in that State.
On the mainland, the populations of a number of species, including the Koala, are already severely affected. Much of the best-quality forest is in private ownership and can be expected to disappear rapidly if current plans for over a dozen new pulp mills around the country, some in areas containing Koalas, go ahead (Map 4.7).
There is great scope for conflict over the allocationfesxe
of forest resources. It seems inevitable that policies for forested public lands will increasingly be overtly oriented towards multiple use, meaning the use of the land for more than one purpose. This brings a need for well-informed and sensitive planning of forest-land use. The starting point for land-use planning is knowing what is there. Unfortunately, Australian forests have never been well inventoried for their wood, water, recreation, wilderness, landscape and plant and animal resources. Without big improvements in inventory work, prospects for conflict resolution are much reduced. A national forest inventory is at present being organised by the Federal Government and this should provide useful context for planning at the strategic level.
There is also great scope for conflict over themanagement practices used by foresters. Three kinds of management operations deserve particular attention because of their potential to affect environmental values:
* intensive timber harvesting
* the planned use of fire;
* the establishment of plantations of exotic pines.
Harvesting techniques involve the removal of either single trees, groups of trees or whole stands (clearfelling). Since the early 1970s when it became widespread, the system causing most public concern is clearfelling. Precautions to protect animal species which depend on old trees or high-nutrient vegetation can be built into harvesting strategies. Erosion and stream siltation are other hazards which can be avoided with careful management.
Annual burning of regrowth is practised on a small area of forest in Australia and State agencies support some research into the cumulative effects of repeated prescribed fires on soils and site productivity, and on flora and fauna conservation. At the same time they pursue a goal of minimising damage to the timber resource by wildfire.
The conversion of eucalypt forest to pine plantations is perhaps the main criticism of softwood afforestation programs. A socially acceptable forest policy probably must contain a large softwood plantation component as this is the only way at present to ensure a large part of our wood supplies in the foreseeable future. Pine plantations represent only about three per cent of forested land, but currently provide about 34% of harvested volume. They grow wood at about 18 cubic metres per hectare per annum which is about 50% higher than well-managed native forests and about 20 times higher than `average' native forests. Hardwood plantations are still very much under trial, but if well managed could enjoy up to double the annual increments of softwood plantations.
Market forecasting is very difficult though and plantings may already be excessive for achieving saleable volumes. However, wherever practicable, and other things being equal, plantations should be established on land already cleared for agriculture. A recently emerging concern, at least in sandy soils, is that second-crop pines may be showing declining growth rates. The same may even be true for regrowth native forests.
The Mineral Zone
Production and exports
Australia is an important world source of minerals and energy (Box 4.2). She has massive resources of black and brown coal in New South Wales (Hunter Valley, south coast) and central Queensland (Bowen Basin). Identified black-coal resources amount to over 54 000 million tonnes. Brown-coal resources are estimated at 46 500 million tonnes, mostly in Victoria (La Trobe Valley) and mostly economically recoverable. However, massive reserves do not necessarily reflect a capacity to influence world mineral markets; that is more a function of production relative to other countries. Box 4.9 shows Australian percentages of Western world production of major minerals.
Rutile concentrate 45.3 1
Zircon concentrate 44.4 1
Bauxite 39.5 1
Alumina 31.8 1
Ilmenite concentrate 22.2 1
Lead 18.4 1
Manganese ore 16.8 4
Nickel 16.2 2
Zinc 12.5 2
Uranium oxide 11.5 4
Iron ore 11.1 2
Silver 9.5 5
Diamonds 9.0 -
Black coal 8.8 -
Tungsten concentrate 8.6 -
Aluminium 8.0 3
Tin 4.6 7
Copper 3.8 7
Gold 3.4 5
Salt 2.2 -
Crude oil 1.2 -
The last ten years
In the late 1970s, the rate of growth of the mineral industry, which had been maintained for more than 15 years, began to slow. New mines had been developed around the world to meet a forecast demand for minerals which turned out to be overly optimistic. The Australian industry's costs had increased, but in general mineral prices had not. The industry, being largely dependent on exports, had to compete with mines elsewhere, some less affected by cost increases and some assisted in various ways by their governments.
Many new coal mines were established in Australia after the second oil shock in 1979, but world demand stagnated, leaving the industry in Australia and elsewhere with surplus capacity. Metal prices failed to increase with the world upturn in the early 1980s, and few new mines were opened; Australian production increased largely because of production increases at existing mines to achieve economies of scale.
Petroleum exploration expenditure increased rapidly
after 1979. Several new commercial
fields were discovered, notably in south-west Queensland and, because of the
greatly increased price of crude
oil, decisions were made to develop some previously uneconomic fields. However, the collapse of prices in the first quarter of 1986 completely changed the fortunes of the petroleum industry. Production fell, mainly because of the cessation of exports; exploration was reduced sharply, and development of a number of fields was deferred.
The destination of mineral exports has changed markedly in recent decades:
of mineral exports 1965-85
(per cent of value)
Europe 41 14
Asia 41 63
America 16 12
Two-thirds of exports to Asia are to Japan and there is now a strong mutual dependence between the two countries. Australian mines have been particularly vulnerable to the state of the Japanese economy in general, and the steel industry in particular.
Major mining centres
The great onshore mining centres of
Australia today include Pilbara (iron ore), Bowen Basin, Hunter Valley, La
Trobe Valley (coal), Eastern goldfields of Western Australia, Weipa, Darling
Range and Gove (bauxite). Individual
mines at Mt Isa, Groote Eylandt, Roxby Downs/Olympic Dam, Argyle and Broken
Hill are well known and important (Map 4.8).
In 1982, Mount Isa Mines accounted for the following shares of national
production: copper 65%, lead 39%, zinc 26%. Mt Isa's proven recoverable lead-silver-zinc reserves are extensive and capable of sustaining current rates of production well into the next century. Offshore there are the two major oil and gas fields of Bass Strait and the North-West Shelf.
Depending on politics and prices, possible future major mining regions include Alligator Rivers region (uranium, gold, palladium), Kimberleys (still little explored) and the Timor Sea (oil and gas).
The Pilbara is a well-established region in which sizeable `company' towns---Mt Newman, Paraburdoo, Tom Price, Goldsworthy etc.---outnumber and overshadow both the old towns and the new `non-company' towns of Karratha, Wickham and South Hedland. The principal mining activities are iron ore, salt and natural gas from the North-West Shelf. The Pilbara has the resources to become a major industrial as well as mining region.
All mining in Australia is undertaken by the private sector, basically a small number of very large companies predominantly under foreign ownership and control and a much larger number of smaller Australian-owned companies. Thirty-one companies receive 94% of all mining income. Profitability of the big traditional mining companies in Australia depends very much on base metal prices and the value of the Australian dollar. However, a new generation of companies is emerging, focusing on a different range of commodities with better operating margins: gold, mineral sands, uranium, platinum and diamonds. To quote Ian Story, `these companies are characterised by low debt, relatively high current profitability, good earnings growth potential, moderate price/cash flow ratios, a significant exposure to gold, minimal exposure to base metals and innovative industrial relations strategies.'
For example, production of gold, the catalyst for Australia's first population boom, has increased in line with world prices and liberal tax concessions in recent years and Australia has the capacity to again become a very large supplier. Much of the current output boom is an attempt to get the stuff out of the ground before tax concessions on gold production are withdrawn.
More processing of minerals occurs in Australia than is generally realised. As with any commercial venture, value-adding processing is undertaken when entrepreneurs judge that the added value is more than the cost of adding it:
* Besides being the world's largest exporter of alumina, we are a substantial exporter of aluminium metal and a sizeable fabricator and exporter of aluminium products to south-east Asia.
* coal does not lend itself to value-added processing;
* commercial prospects for an iron and steel industry have never been good;
* BHP is contemplating a manganese dioxide plant;
* high-quality Inverell sapphires and Argyle diamonds are starting to be cut in Australia, a value-doubling process;
* Pancontinental Mining Ltd is developing the
world's largest deposit of magnesite at Kunwarara in Queensland, including its
magnesia. While raw magnesite fetches about $US 75 per tonne, magnesia fetches about $US 400 per tonne.
* In copper, nickel, lead, zinc we export refined metals, but do not go further except for the home market. The reasons lie in economics and market strategy. We produce refined and substantially processed nickel mainly for marketing reasons; if we had not established our own processing capacity in Australia, we would have been at the mercy of our competitors in a small market. To protect our own industry, quoting mining magnate Arvi Parbo, we have gone into processing these ores beyond what we should economically.
Because modern mining is capital-intensive with relatively low running costs and small wage bills, its multiplier effects in terms of inducing production and consumption in other sectors of the economy are relatively low.
Mining and other land uses
In the 1950s, the mining industry began to be affected by increasing public concern for `the quality of the environment'. Faced with a rising awareness that preservation of natural features such as scenery and plant and animal habitats had a value to society, governments increased the controls on discharge of potentially polluting emissions such as water containing sediments or chemicals and noxious gases. Whereas the industry once, by and large, had priority in land use, it now had to justify its activities in competition with other potential uses of the land. Governments also began to take account of the likely effect of a proposed mine or processing plant on the surroundings before deciding whether it should go ahead, and required that, where feasible, mined-out areas be rehabilitated by reshaping and revegetating the surface so that the site could be used for other purposes.
Most mines and mining settlements are raisins in the agricultural or pastoral cake. Per unit area, mining can be worth immensely more than agriculture. In Victoria, mines of the last century rarely occupied more than a hectare and some produced over $150 million worth of gold at today's prices. Today, careless gold mining, damaging to land and water alike, is infuriating environmentalists, particularly around Bendigo,Ballarat and Stawell.
While it is true that even open cut mining takes little land compared with agriculture and forestry, it can impose environmental and resource impacts over large areas for long periods. This is particularly true of large dust-producing, noisy, water-demanding coal-energy operations located in the more densely settled areas of the Ecumene. Hunter Valley, Latrobe Valley and the prospective Rundle operation are good examples. Still, I am inclined to agree with Cliff Ollier that
If we look at the impact of mining in detail we find some genuine environmental problems and some genuine answers from the mining industry. We also find that the standards expected of the mining industry differ from those expected of other activities, that the mining industry is suffering from `selective indignation' ...
Part of the explanation could be that the industry is largely foreign-owned and has thrown up an unfortunate number of confrontationist spokespeople who have served their industry poorly. At various times, the mining industry has come into conflict with practically everybody---Aboriginals, conservationists, farmers, urban residents. Recently, the Pacific Asia Travel Association warned that mining in Kakadu could threaten the international tourist trade on the grounds that visitors come to see unspoilt wilderness, not mining.
Apart from direct destruction of relatively small areas of land (perhaps in ecologically significant areas though), environmental issues surrounding mining focus on waste disposal, rehabilitation, water management and nuisance problems (dust and noise). Rehabilitation demands on miners are far more stringent than on farmers who overgraze, foresters who clearfell, irrigators who induce salinisation.
Land utilisation in Australia
Two men looked out of prison bars,
One saw mud, the other stars.
How well are Australians using their island
continent? Within the perceptions of times past, we have made reasonably good
use of the opportunities presented by Nature.
We have sensibly
concentrated our population in pleasant medium-sized cities in the subtropical to cool-temperate regions. After a late start, we have done well in exploiting our minerals. We have made the most of limited timber resources, running down native hardwood supplies, but building up high-yielding softwood plantations. We have achieved major status as suppliers to the world of wool, meat and wheat, developing numerous innovative technologies along the way. At least in the south, we have comprehensively harnessed the little surface water we have. We have protected such major natural features as the Barrier Reef and the rainforests; our national park system is extremely well developed by world standards. We have used our resources to build a prosperous and pleasant society.
True, we have not learned how to use productively and sustainably the wet-dry tropics, the drier, droughtier rangelands or the continental shelf. We may be about to come a cropper with our temperate and subtropical systems (erosion, salinisation, acidification), with our fishing industry (overfishing) and with the rangelands (falling carrying capacity). But, surely, if we heed the warnings and grasp the opportunities, such difficulties will be overcome.
I have no quarrel with this optimistic view of the way we are using the place. It is important nationally, just as it is personally, to have a positive view of oneself and one's achievements. All I ask is that we remember the Easter Islanders.
Land use is a one-way street
Virgin land can have a range of use possibilities which can be typed in terms of the degree to which they imply alteration of the original natural systems, viz.:
* Extreme to total alteration: Habitats for most indigenous species are greatly altered or destroyed; very few species are able to persist or reinvade; species composition is drastically simplified or composed of introduced species. Examples include high-density urbanisation, intensive horticulture, infilled wetlands, large dams and mining operations.
* Highly altered/modified: Here, a range of indigenous species persists, but sensitive species die, become vulnerable or reproduce erratically; many exotic species are frequently present; the range of plant forms present is likely to be reduced; age distributions of populations of some species are likely to be restricted. Examples include crop-pasture agricultural systems, low-density residential areas and clearfelled native forests.
* Low degree of alteration: Here, the main effect of using natural systems lightly is that a proportion of species will be lost; introduced species may be present, but a majority of species is likely to be indigenous; the age distribution of populations of some species is likely to be modified; relative species abundance may be altered, but the system is effectively stable. Examples include undegraded rangelands, selectively logged forests and managed waterways.
* Essentially unaltered: System behaviour here is within the original range of