Strategies for managing corn crop residue in the context of greenhouse gas emissions

Food production is one of the most important sources of greenhouse gas (GHG) emissions, both in primary production and in processing and the logistics chain. The most problematic and risky is the optimization of environmental effects in the stage of primary production. This is due to the significant influence of factors related to climate and soil that are difficult to predict. The scientific literature offers much information on the impact of crop residue management, but the context for assessing the impact of crop residue management in corn production on the carbon footprint is still unclear. The effectiveness of using organic additives like biochar, compost, corn, or straw to maintain soil productivity is well acknowledged. Information about the effects of particular crop residue management strategies on soil carbon sequestration, soil quality, and crop yield in corn cultivation is currently scarce. The research aimed to assess the potential for optimizing corn production through modifications in crop residue management, with a focus on the efficiency indicator being the level of greenhouse gas emissions per functional unit of the product. A 3-year growing experiment was conducted to investigate the impact of different corn crop residue management strategies. The modifications of the corn cultivation technology in terms of the crop residue management strategy had a significant impact on the yield of plants and the amount of GHG emissions. The conversion of corn straw to biochar and its introduction into the soil reduced the GHG emissions from corn cultivation per functional unit, despite the energy expenditure related to straw transport and biochar production. From a 3-year time perspective, a beneficial effect of biochar addition on the size of the commercial yield of plants was observed. In variants with biochar and a reduced level of nitrogen fertilization, no reduction in yields was observed. This confirmed the hypothesis that biochar could be a useful material for the production of slow-acting fertilizers.