Emissions advantages for Australian grain producers revealed

A LEADER researcher in the team that compiled a report into the Australian grains industry's carbon emissions has said the figures which show Australian grain growers have some of the lowest emissions in the world are reason for optimism for the industry.

While she said it was unknown how other key grain producing nations that ranked as emitters under old International World Food LCA Database (WFLDB) accounting system CSIRO senior research scientist Maartje Sevenster said the methodology used in the recent CSIRO report far better demonstrated Australia's true emissions when producing grain.

"We don't know for sure, but I'd very confident it would not be a case of every other nation using this updated methodology and again coming up with a figure lower than the Australian number," Dr Sevenster said.

In terms of its status as a low emissions producer Dr Sevenster said Australia's low carbon soils, bemoaned by farmers who previously tried to participate in soil carbon sequestration schemes, were actually beneficial in many ways in carbon accounting.

"It seems odd but having low soil carbon is almost an advantage."

"Low carbon soils are easier to keep constant or to even increase carbon levels a little.

"You do see in Australia's cropping regions with higher carbon soils, such as the Liverpool Plains (NSW) and parts of Queensland that there is the potential to lose carbon, especially in some of those poorer seasons."

She said Australia's notoriously volatile climate meant Australia had by far the biggest deviation from the mean in terms of emissions.

"This means there can be substantial biases there if you don't conduct the study over a longer period, you could use the average fertiliser requirements over a drought year with low production which in turn would markedly increase the in-theory emissions."

Dr Sevenster said other reasons for the drop from 498kg of greenhouse gas per tonne of wheat under the International World Food standards to just 307kg/t under the CSIRO accounting could be an overly high figure for fertiliser application in the initial work.

"It was likely that the assumed nitrogen use for Australia was high, so we are now digging further into that."

Dr Sevenster said other factors her team had found while compiling the Australia Grains Baseline and Mitigation Assessment report for the Grains Research and Development Corporation (GRDC) was that there could be big variations within Australia's climatic zones.

"Australia is very big, and the cropping systems are different from the other major grain producing nations."

She said researchers also had to accurately get the mix of farmland use.

"People do not always just grow grain, Australia has a high percentage of mixed farms and there are calculations there to figure out what emissions are caused and how."

Dr Sevenster said improving fertiliser application would also contribute to lower emissions per tonne.

"At the time the initial work was done it was done without advances like slow release nitrogen or variable rate application."