Most growers view soil organic matter as a key component of soil productivity, but the capacity to increase organic carbon (measurable component) in soil is constrained by soil type, climate and – to a lesser extent – management. Detectable changes usually occur slowly, over decades though losses associated with erosion or soil disturbance can be rapid.
Research suggests the most profitable way to manage soil carbon was to improve plant growth by removing soil constraints to production (i.e. soil acidity) and retaining crop residues. Adding organic amendments could increase soil carbon but was only achieved at high cost.
Key research outcomes on soil organic matter were communicated to more than 2,500 growers, advisers and industry representatives in WA (2012 to 2015). Workshops, field days and trials looked at innovative strategies to increase soil carbon, while changes in carbon stocks seven years on were undertaken with 39 participating growers.
This project (DAW00225) was undertaken while an employee of the Department of Agriculture and Food Western Australia (DAFWA). Research was funded by the Grains Research and Development Corporation (GRDC) in partnership with the lead research organisation DAFWA.