"These sites are pockmarked across the southern tablelands," says Ive, shaking his head in despair at desertification of Australia's farmlands as underground salt rises to the surface.

Only the Sahara has more desert than Australia, whose red centre has long been thought uninhabitable by modern man.

But while Australia's central deserts are now seen as benign and are starting to yield fruit, salination is turning once productive farmland into lifeless dirt tracts and threatening the country's A$30 billion (US$22 billion) agriculture export industry, one of the biggest in the world.

Around 2 million hectares (5 million acres) of land is now officially salt-affected, half of that in southwest Western Australia.

The amount of saline land could rise to 6 million hectares (15 million acres) in 50 years, but that would be the upper limit, says Kevin Goss, chief executive officer for the Cooperative Research Centre for Plant-based Management of Dryland Salinity.

Farmers are terrified of the salt, which cuts land values by one-third and reduces output.

Prime Minister John Howard has rated salinity as one of the biggest environmental challenges facing the country and has backed a A$1.4 billion national action plan.

The most celebrated win so far is the reversal of salinity in Australia's biggest river, the Murray, through a combination of engineering works and management of water flows. A national tree-planting campaign is being accompanied by the use of salt-tolerant plants to combat growth of desertification.

FIGHTING BACK

The salt-ravaged land adjacent to Ive's Dicks Creek farm is a mere 35 km (22 miles) from the national capital, Canberra.

Ive bought his 250-hectare (620-acre) property in 1980 to run sheep and cattle. His land was then badly degraded, with active saline seeps on 23 percent of the property.

When it rained, water raced down from rocky bare ridges into the more fertile gully below, further eroding soil and raising the subterranean water table, bringing salt to the surface.

But Ive fought the creeping death that salt brought to his land. He put in contoured and graded banks of land on the hillsides and into the valley to control water rushing down from the ridges. He improved the soil on the gully pastures then put stock up on the rocky ridges when drought threatened.

"The sheep can turn the hills into a moonscape, but they are not prone to erosion because they are so rocky," says Ive, as he proudly looked down on a green valley as a winter wind buffeted a row of planted trees behind him.

When it rained, Ive took sheep off the hills to allow native trees to germinate without competition. Now he has 200,000 hilltop trees. Elsewhere he planted 25,000 furniture-grade trees.

Today, green pastures slope up a ridge thickly wooded with trees on Ive's side of a boundary fence.

On the other side, the hilltop is bare, a scratchy pasture is dotted with skeletons of dead trees and salt patches have eaten to the edge of the fence. Desertification is at the doorstep.

Ive points to a nearby metal drum. It contains a piezometer, a piece of plastic tubing sunk into the earth to measure the depth of the water table beneath.

Over the last 25 years, the water table on Ive's farm has dropped from earth-surface level in places to seven metres depth.

Now only two percent of his property is affected by saline seeps. Water salinity has fallen from up to 20,000 electrical conductivity units to about 60 -- better than Canberra drinking water which has 120.

But not all farmers have been able to perform Ive's "balancing act" between farm production and farm protection.

Most of Australia's 400,000 farmers and family members are still coming to grips with the fight against salinity, which is most widespread in agricultural areas between the vast outback deserts and the coast.

OUTBACK DESERTS GROWING

The outback deserts are also growing, due to climate change. Officially, lowland arid regions cover 3.6 million square km (1.4 million sq miles) of Australia's heart.

"Central Australia will get drier. And the periods of drought are likely to get more ferocious," says Professor Mike Archer, a longtime desert enthusiast and dean of science at the University of New South Wales.

Feral predators, tourists, grazing animals and big fires are all adding to pressures on Australia's deserts, after already making 20 or more mammal species extinct. But it is not all bad.

"Our deserts are in pretty good nick (shape)," says Mark Stafford-Smith, research scientist with the Commonwealth Scientific and Industrial Research Organisation (CSIRO).

"We've got these remarkable areas which are 70 percent of the continent and have some extraordinary biodiversity."

A growing love affair with Australia's deserts is pushing the CSIRO and others to develop a potentially lucrative bush tucker (native food) industry, new medicines from desert plants, salt-tolerant wheat and genetically engineered tomatoes, as well as sustainable harvesting of kangaroos and native plants.