Farm Table says:
The take home messages from this GRDC funded research are below. Please access the full paper via the link below for methodology, references, acknowledgements and discussion.
Take home messages from the paper include:
- Preserving or enhancing soil organic matter stocks is critical to sustainable agriculture, due to its key role in soil health, plant productivity and building resilience. Stubble return with strategic nutrient inputs (‘integrated stubble-nutrient management’) has been proposed as a measure to build soil organic matter in cropped soils.
- The supply of extra nutrients along with wheat stubble enhances stocks of stable soil carbon if wheat stubble input is high (12t/ha), which is unlikely under rainfed conditions in normal seasons. At more common rates (less than or equal to 4t/ha), there may be no benefit on improving stable soil organic matter through the integrated stubble-nutrient management.
- Where stubble input is high, the addition of extra nutrients considerably enhances microbial biomass, potentially leading to build-up of stable organic matter, especially in clay soils.