A study led by The University of Western Australia is investigating whether increasing soil carbon in grain production to offset greenhouse gas emissions may also increase nitrous oxide emissions, which are nearly 300 times more damaging than carbon dioxide.
The project is based in WA's grain belt and funded by the Commonwealth Government's ‘Filling the Research Gap' project, which forms part of its Carbon Farming Futures Program, in partnership with the Grains Research Development Corporation (GRDC), the Department of Agriculture & Food WA (DAFWA), and the Liebe Grower Group.
UWA researchers will examine whether there is a risk that increasing soil carbon will also increase soil nitrous oxide emissions and burden famers with additional nitrogen fertiliser requirements for cropping soils.
"Increasing carbon in soil is promoted as a means of off-setting greenhouse emissions from grain production, however we need to check that this benefit is not negated by increased soil nitrous oxide emissions or additional nitrogen fertiliser requirements," Associate Professor Louise Barton, from UWA's Soil Biology Group and the UWA Institute of Agriculture, said.
"Nitrous oxide is a particularly potent greenhouse gas as it is almost 300 times more damaging than carbon dioxide, so it is crucial that we ensure emissions of this gas from agricultural soils are minimised. Furthermore, nitrogen released from the soil into the atmosphere represents a loss of N fertiliser available to crops."
The three-year study has been established at Buntine - about 250km NNW of Perth - where the Liebe Grower Group has successfully increased soil carbon as part of a previous research project which commenced in 2003. Nitrous oxide emissions will be measured at the Liebe Group's Long Term Soil Biology Trial using an automated chamber system. At the same time, crop responses to nitrogen fertiliser will be measured in experimental plots of contrasting soil carbon, and then be compared further with data from other sites in the Western Australian grain belt.
"The trial site at Buntine provides a unique opportunity to study the effect of increasing soil carbon on other greenhouse gas emissions and we are very pleased to have the opportunity to work with the Liebe Group", Associate Professor Barton said.
Results from the study will be used inform growers and policy on the effects of increasing soil carbon on the carbon-foot print of grain production in Western Australia.
Associate Professor Louise Barton (UWA School of Earth (+61 8) 6488 2543 / (+61 4) 08 197 061
and Environment and The UWA Institute of Agriculture
Ully Fritsch (Communications and Development Officer, The UWA Institute of Agriculture) (+61 8) 6488 3756
Michael Sinclair-Jones (UWA Public Affairs) (+61 8) 6488 3229 / (+61 4) 00 700 783