The Sustainable Cropping Rotations in Mediterranean Environments (SCRIME) experiment started 25 years ago to examine the impact of different crop and pasture rotations and tillage systems on agricultural productivity in medium rainfall climates in southern Australia.
Agriculture Victoria senior soil scientist Roger Armstrong said data collected from the last soil monitoring campaign in 2018, prior to recent wetter years, showed soil carbon was declining to varying degrees across all crop rotations.
“The crop rotation that had the least decline in soil carbon was one that included a high frequency of legumes in its rotation,” Professor Armstrong said.
“Crop rotations weren’t able to halt the slow decline of soil carbon, even when zero tillage residue retention systems were adopted.
“Since 2018, however, the Wimmera region has returned to a series of better seasonal conditions so it will be interesting to see how the different rotation and tillage systems we are examining have impacted on soil carbon.
“Soil is a precious resource that underpins the profitability and sustainability of farming and soil carbon is another challenge for farmers to manage alongside changes in climate, cropping systems and the market.”
SCRIME is part of Agriculture Victoria’s long-term trial network and this round of soil carbon monitoring is a co-investment between Agriculture Victoria and the Wimmera Catchment Management Authority (WCMA).
“SCRIME and other Agriculture Victoria’s long-term trial experiments are a unique research asset in Australia that allow researchers and growers to assess how different farming practices affect productivity, water use efficiency and soil across a range of seasons, something not possible in short-term experiments,” Prof Armstrong said.
