How Australia's vast rangelands work, what makes them fall apart and how to bring them back again are the subject of a major new book, the result of 30 years of research by CSIRO scientists.

The book provides a fresh way to understand and look after the arid and semi-arid expanses which cover 5.5 million square kilometres, or three-quarters, of the continent.

Landscape Ecology, Function and Management, by authors John Ludwig, David Tongway, David Freudenberger, Jim Noble and Ken Hodgkinson will be launched in Canberra today by Senator Julian McGauran, Senator for Victoria.

Rangelands support grazing, mining, defence activity, tourism, traditional uses and introduced pests as well as unique native plants and animals. Resources are sparse, environmental pressures immense and large areas have been degraded in the past century.

The book creates a new way to view the enormous complexity of the rangelands, helping landholders to "read the land" and predict the results of their management decisions.

The Outback is about patchiness and variation ­ not about uniformity, says co-author Mr David Tongway. Patches form the hot-spots of diversity in its life.

"It is these small, rich patches which support the myriad of organisms which keep the soil alive and breathing.

"Patches are the 'wicks' in the system. They help capture moisture and wind-and water-borne nutrients, and transport them into the soil where plants can use them," he says.

"Patches are the small-scale elements of larger scale patterns, many of which can be seen by satellites."

Mr Tongway warns that if the Outback becomes too uniform, and loses this essential variety and complexity, it begins to fall apart. Overgrazing and other land-uses can have this effect.

"The take-home message is that we have to look after our patches ­ by reducing grazing and other pressures at the right times, by burning at the right times, by rebuilding patches of brush where needed."

Mr Tongway says the book is intended to help land managers develop sustainable practices through a fresh insight into how rangelands work. It is aimed at professional land managers, graziers, Aboriginal land holders, the military and the mining and tourist industries.

"This is the first time we have taken an integrated approach to managing the landscape," he says. "We have brought together many scientific disciplines to give us a new way to look at the landscape and understand how it works."

The authors discuss problems that confront land managers such as desertification, minesite rehabilitation, conservation of habitats and biodiversity.

"Our book shows how to figure out how rangelands work to the extent that the nature of the problem and how to fix it are both revealed. We also say that a landscape can be partially broken. Some people think degradation means that the land is destroyed beyond repair, but there is a gradation of damage. It may not be as bad as it looks," Mr Tongway said.

"Basically we are giving information that will help people recognise the warning signs and step in before things go wrong," Mr Tongway said.

The lessons of the Outback also hold benefits for rangeland areas in other parts of the world. Mr Tongway has already been involved in parallel research in Iceland, South Africa and the United States.

The launch will take place today, Wednesday, September 3, 1997 at 11.00 am at the Old Seminar Room, CSIRO Wildlife and Ecology, Gungahlin, Barton Highway ACT.

More information:
Mr David Tongway 02 6242 1641
Dr David Freudenberger 02 6242 1607

Photo opportunities:
There will be photographic opportunities of a rangelands montage, with red soil (not actually degraded), and typical animals.