A map of Australian annual median rainfall reveals how arid and semi-arid environments occupy the largest land surface in Australia.
Sustainability in Australia's arid lands
A sustainable future for Australia's unique arid and semi-arid ecosystems will depend on applying science to understand the complex interactions between livelihoods and landscape management in a harsh and uncompromising environment.
6 June 2008 | Updated 14 October 2011
Australia's arid lands
The arid and semi-arid lands are the remote and sparsely-populated areas of inland Australia, defined by the presence of desert vegetation and land forms as well as by low rainfall. They are bound by median annual rainfalls of about 250 mm in the south but up to 800 mm in the north and about 500 mm in the east.
Together with sub-tropical regions and the mountain high plains, they form the rangelands, where rainfall is too low or unpredictable or where terrain is too inhospitable for sustainable cropping or timber harvesting. The rangelands amount to 70 per cent of Australia's land surface. By far the largest part is arid or semi-arid.
It is an uncompromising environment at times but never monotonous. The climate of arid Australia is characterised by highly erratic rainfall, extremes of long dry periods and occasional flooding. As well, soils are very infertile over vast areas compared to other deserts of comparable aridity.
The rangelands amount to 70 per cent of Australia's land surface, and by far the largest part is arid or semi-arid.
The range of flora and fauna occupying the various ecosystems also contrasts with that from other arid regions of the world. Major differences include:
- the lack of many succulent plants
- the small number of large mammals
- the high numbers and diversity of lizards and social insects such as ants and termites.
These factors combined contribute to the arid zone's particular character.
Sustainable land use
Despite the challenges of climate and terrain, there is a diversity of land uses. The balance amongst them is changing with global market forces and community values.
The pastoral industry is the major land user, producing mostly cattle in the north and sheep in the south, but profitability is difficult to maintain in some areas.
Other land uses currently include:
- Indigenous cultural and subsistence activities
- harvesting of wild animals and plant products
- small-area intensive industries such as horticulture.
Some of these are growing rapidly.
Newer, developing industries include:
- hot rock geothermal energy
- carbon sequestration
- low intensity lifestyle activities.
Most Australians regard the 'outback' as part of the nation's heritage. Although Australians reside mostly in urban and coastal areas, many retain a romantic image of the outback pioneers. Realities are different today. Australia and indeed the world is concerned about land care and the preservation of land use options for future generations. Whoever uses this land must come to terms with its variability and sensitivities or risk compromising its rich potential.
The obligation to maintain the arid lands is shared by many groups of people. In collaboration with these groups CSIRO's role in the arid zone is to provide governments, private agencies, individuals and the broader community with:
the knowledge of how the arid lands function
the principles for their management
the methods that can be applied to achieve sustainable land use.