A Survey of Agronomic Management Studies Aimed at Mitigating Nitrous Oxide Emissions from Agricultural Soils

A major concern in our modern world is the emission of the greenhouse gases carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) into the atmosphere and their effects on climate change. Due to their significant impacts on carbon and nitrogen dynamics, agricultural activities have both direct and indirect effects on soil greenhouse emissions. Nitrous oxide is a potent greenhouse gas with a global warming potential of 298 times that of carbon dioxide. Most N2O emissions are agriculturally-induced, occurring due to nitrification and denitrification processes in soils and strongly affected by various environmental and soil management factors. The present review paper attempts to evaluate the capability of different agronomic management practices in mitigating nitrous oxide (N2O) emissions from agricultural soils. Proper management of crop residues, application of new methods of conservation tillage and irrigation techniques, and inclusion of legume crops in crop rotation programs are reportedly among the measures effective in reducing nitrous oxide emissions. Moreover, the use of nitrification and urease inhibitors as well as sustained-release fertilizers to improve nitrogen use efficiency might lead to reduced nitrous oxide formation and emission. From a different perspective, the use of novel technologies to identify the sources of nitrous oxide is of great importance in the selection and application of proper farm operations aimed at preventing further greenhouse emissions. It is expected that the agronomic management strategies proposed herein might have significant contributions to reducing nitrous oxide emission from soils, abating or preventing global climate change and the associated global warming, and achieving sustainable agricultural production.