Sensitive variables for applying biochar as a fertiliser substitute and a method to sequester carbon in soils: a wheat crop scenario

This research reviews the displacement of phosphorus fertilisers in wheat cropping regions using biochar (biologically derived charcoal). The research aim was to assist agriculturalists to navigate soil carbon mitigation incentives using iterative planning processes, enabling a balanced approach between soil biochar sequestration, conventional productivity co-benefits, and attitudes to risk. This research quantifies conventional productivity benefits from the adoption of carbon soil sequestration, and the value of carbon sequestered, with scenarios for various prices for biochar, single superphosphate, and carbon. The biochar sequestration modelling results indicate that a reduction of phosphorus fertiliser use in cropping regions was possible when applying large quantities of biochar to the soil. The cost-effectiveness of using biochar in cropping systems was found to be insensitive to phosphorus fertiliser price or carbon market values. In contrast, the commercial viability of using biochar in cropping systems was highly dependent on the price of biochar.