ABSTRACT

Agricultural land occupies nearly half of the earth’s surface, and farming activities account for nearly 60% of total anthropogenic N₂O emissions. The manufactured nitrogen (N) fertilizers applied to soils are major sources of N₂O emissions from agricultural systems. Among the synthetic N fertilizers, urea has the highest nitrogen content of all solid nitrogenous fertilizers and accounts for 66% of global synthetic N fertilizer use. Hence, efficient urea-N management is imperative for global N₂O abatement. This review provides an update on advances in N₂O-generating pathways, microbial mechanisms, abiotic and biotic regulating factors, and mitigation strategies. Nitrification inhibitors have been extensively studied as strategies to mitigate soil N₂O emissions by decreasing nitrification and denitrification processes. Controlled/slow-release fertilizer formulations have been used widely to enhance fertilizer N use efficiency by regulating the release rates of N from fertilizer. Additionally, biochar, microbial inoculation with arbuscular mycorrhizal fungi (AMF), biological nitrification inhibitors (BNIs) and biological denitrification inhibitors (BDIs) may enable the development of novel and environment‐friendly strategies for practicable N₂O mitigation in future.

摘要

农业用地占地球表面的近一半，农业活动占人为 N ₂ O 排放总量的近 60%。_{施用于土壤的人造氮 (N) 肥料是农业系统中 N 2} O 排放的主要来源。在合成氮肥中，尿素是所有固体氮肥中含氮量最高的，占全球合成氮肥用量的66%。因此，有效的尿素-N 管理对于全球 N ₂ O 减排至关重要。_{本综述提供了 N 2}进展的最新情况产生氧气的途径、微生物机制、非生物和生物调节因素以及缓解策略。硝化抑制剂已被广泛研究为通过减少硝化和反硝化过程来减轻土壤 N _{2 O 排放的策略。}控释/缓释肥料配方已被广泛用于通过调节肥料中氮的释放速率来提高肥料氮的利用效率。此外，生物炭、丛枝菌根真菌 (AMF) 微生物接种、生物硝化抑制剂 (BNIs) 和生物反硝化抑制剂 (BDIs) 可能有助于开发新的和环境友好的策略，以实现未来可行的 N ₂ O 减排。