Transcript: Getting the dirt on elevated CO2
Associate Professor Roger Armstrong:
Welcome to SoilFACE. SoilFACE is part of the AGFACE program here in Horsham. AGFACE is an outdoor laboratory where we're looking at the effects of elevated CO2 that’s expected to occur in 2050 and what we're aiming to do in the AGFACE program is to make predictions of how the grain crops grown for, not just The Wimmera, but throughout Australia, will perform under future elevated CO2 environments.
In SoilFACE, as the name implies, the focus is on how different soil types interact with the elevated CO2. In the SoilFACE bunker here, for example, we have 50 different large, intact cores. Those cores have been collected from the major grain growing regions of Victoria; from the sands, from The Mallee, The Wimmera crack and clays, from the heavy clay soils of the high rainfall zone of Victoria. And what we do in SoilFACE is we grow a rotation of field peas and what and look at how the CO2 affects the interaction between the crop growth and the soil properties.
In SoilFACE a major focus is on nutrition, particularly nitrogen, and also carbon. As the work from overseas implies, that elevated CO2 has major effect on nitrogen cycling. That in turn translates through to the effects on crop growth and grain quality.
Early results in SoilFACE have shown that elevated CO2 stimulates crop growth and nitrogen uptake, and also the amount of nitrogen fixed by the legumes. So in effect, the legumes will supply a greater quantity of nitrogen to the following cereal crops.
In the future we’re having detailed examination of how the elevated CO2 will affect nitrogen mineralisation rates, as well as the amount of nitrogen and carbon that’s distributed below ground in the soil, because that in turn will affect nitrogen supply capacity of the soil to the crops, as well as the amount of carbon sequestered in the soil.
The AGFACE is a joint project with the University of Melbourne and is partially funded by the Grains Research Development Corporation.