Global soil map in five years

University of Sydney scientists are behind a technology that will map most of the ice-free land surface of the globe over the next five years in order to create something akin to a "Google Earth" for soil quality.

Professor Alex McBratney, Director of the University of Sydney's Australian Centre for Precision Agriculture, said the maps will provide information about the soil at about every 100 metres across the world. Current maps are at the scale of one to five million.

The idea is to bring soil knowledge into the digital age and to help the international battle to secure food resources, Professor McBratney says. "These maps will give us a good estimate of the production capacity for all kinds of crops all over the world, in some billions of places across the world."

Professor McBratney is working on the project, GlobalSoilMap, with a consortium of scientists in major agricultural organisations across the world. They are calling for greater recognition of the role soil plays in determining the planet's health.

The technology also has an important role to play in improving current climate change models, McBratney says. "The soil information that we produce will help global climate models by providing more detailed information about soil, which produces a lot of CO2 and sequesters a lot of carbon. The current information about soils in those areas is pretty poor."

The maps are using state-of-the-art and emerging technologies, including remotely sensed data from satellites and sophisticated geo-statistical models. These novel approaches are referred to as Digital Soil Mapping (DSM). Using GPS receivers, field scanners, and remote sensing combined with other data, DSM processes information using computational methods such as geo-statistical interpolation, inference algorithms and GIS.

McBratney says his team has developed a number of approaches depending on the amount of prior soil and environmental information available. In Australia the information will help policy makers, catchment management authorities, and ultimately farmers in agricultural planning and management.