The retention of crop residues is now one of the cornerstones of current farming systems. Residues help protect the soil from wind and water erosion, keep the soil cool so as to preserve precious water, and also help cycling of nutrients. Heavy and tangled stubbles can create problems at seeding, provide habitats for pests and diseases and present problems with pre-emergence herbicides. As a result, there may be a need to burn crop residues., and burning may be an option.
However, when residues are burned, up to 80% of the N and S contained in the stubble is lost, and around 40% of the P and K. So, there is a loss of nutrients and the soil is left bare, and so presents an erosion risk until seeding.
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