The Impact of the Soil Environment and Surface Mulching on N2O Emissions from Farmland

A reduction in emissions of nitrous oxide (N2O), one of the three major greenhouse gases, is important for achieving environmental sustainability and carbon neutrality goals. Agricultural fields are the primary source of N2O emissions, and their management measures influence greenhouse gas emission reductions and the greening of agriculture. Among these practices, cover cropping plays a key role in promoting sustainable agricultural production as a major cropping technique for efficient water use and increasing crop yields in water-scarce regions worldwide. The present paper systematically reviews the influence of various soil environmental factors, such as soil temperature, moisture, pH, carbon, and nitrogen contents, as well as nitrogen cycle-related enzymes, microorganisms and mulching practices, including general mulching and straw mulching, on N2O emissions from agricultural fields. This review suggests that future research should explore the long-term effects of different mulching materials and their application rates and durations on soil N2O emissions. Furthermore, a networked mathematical model for causal analysis should be employed in future research to elucidate the relationships among soil environmental factors, nitrogen cycle microorganisms, and soil N2O production and consumption. These future studies will help to deepen our understanding of nitrogen cycling processes in agroecosystems with the aim of developing environmentally friendly agricultural technologies and promoting green and sustainable agricultural development.