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CSIRO unearths clues about the land

If the pun weren't so corny, you'd call the work ground-breaking. Suffice to say, a gargantuan effort headed by the CSIRO to map the state of Australia's soil is unique.

The project divides the continent into two billion "pixels", each representing 90 square metres, and reveals what lies beneath our feet to a depth of two metres.

Known as the Soil and Landscape Grid of Australia, the maps are being launched at a national soil science conference in Melbourne on Wednesday.

Among its many offerings, the maps show nitrogen levels (an indicator of soil fertility), the capacity of soil to retain water, pH levels (evidence of soil acidification) and other indicators of soil quality. The work also reveals topographic details such as the slope of the landscape, solar radiation levels and how far you'd have to dig to hit bedrock.

While none of this is dinner party banter, the information is essential for farmers managing crops, or guiding miners in their exploration for minerals or even situating infrastructure projects, which can use data about soil types when deciding where to build a road.

The work is the culmination of three and a half years' work, $3.5 million and co-operation from 13 organisations, said the project's leader, Mike Grundy, who is a research director in the CSIRO's Agriculture Flagship.


The grid weaves together a bewildering array of data, from topographical information captured during a space shuttle mission in the 1990s, to satellite photography and airborne pictures captured by private companies.

It also integrates data from mineral explorations, climate records, remote sensor data, soil samples and more.

Even with all that material, though, the team still needed to use advanced statistical methods to fill in the blanks of Australia's landscape.

Much the work involved simply finding ways to weave all this disparate information together. The challenge to do so was set in 2006 when soil scientists from around the globe met in the US and agreed there was a need for all countries to work towards this.

"Australia is the first to have done it," Grundy said. "And the first to have done it for a whole continent. It's a global first, but it's part of a global effort."

The work in developing a common language for the various data types will now help other countries replicate the project, he said.

The raw data is freely available, although for the general public the data is available via Google Earth and downloading a navigational file from the project's website, www.clw.csiro.au/aclep/soilandlandscapegrid/.

Grundy said the maps provide a benchmark, a where-are-we-now snapshot. Next steps, he said, were to start interrogating the results and see what light they shed on some of the country's pressing issues, such as biodiversity, climate change, soil salinity and erosion.