The global potential for mitigating nitrous oxide emissions from croplands

Agricultural activities contribute almost half of the total anthropogenic nitrous oxide (N2O) emissions, but proper assessment of mitigation measures is hampered by large uncertainties during the quantification of cropland N2O emissions and mitigation potentials. This review summarizes the up-to-date datasets and approaches to provide spatially explicit and crop-specific assessment of the global mitigation potentials. Here, we show that global cropland N2O emissions have quadrupled to 1.2 Tg N2O-N year−1 over 1961–2020. The mitigation potential is 0.7 Tg N2O-N without compromising the crop production, with 86% from optimizing nitrogen fertilization, three-quarters (78%) from maize (22%), vegetables, and fruits (16%), other crops (15%), wheat (13%), and rice (12%), and over 80% from South Asia, China, the European Union, other American countries, the United States, and Southeast Asia. More accurate estimation of cropland N2O mitigation potentials requires extending the N2O observation network, improving modeling capacity, quantifying the feasibility of mitigation measures, and seeking additional mitigation measures.