Nitrous oxide (N₂O) emitted from wastewater treatment plants has caused widespread concern. Over the past decade, people have made tremendous efforts to discover the microorganisms responsible for N₂O production, elucidate metabolic pathways, establish production models and formulate mitigation strategies. The ultimate goal of all these efforts is to shed new light on how N₂O is produced and how to reduce it, and one of the best ways is to find key opportunities by integrating the information obtained. This review article critically evaluates the knowledge gained in the field within a decade, especially in N₂O production microbiology, biochemistry, models and mitigation strategies, with a focus on denitrification. Previous research has greatly deepened the understanding of the N₂O generation mechanism, but further efforts are still needed due to the lack of standardized methodology for establishing N₂O mitigation strategies in full-scale systems. One of the challenges seems to be to convert the denitrification process from a net N₂O source into an effective sink, which is recommended as a key opportunity to reduce N₂O production in this review.

废水处理厂排放的一氧化二氮（N ₂ O）引起了广泛关注。在过去的十年中，人们付出了巨大的努力来发现负责N ₂ O产生的微生物，阐明代谢途径，建立生产模型并制定缓解策略。所有这些努力的最终目的是阐明N ₂ O的产生方式和减少方式，而最好的方法之一就是通过整合获得的信息来寻找关键的机会。这篇评论文章严格评估了十年内在该领域获得的知识，尤其是在N _2中生产微生物学，生物化学，模型和缓解策略，重点是反硝化作用。先前的研究极大地加深了对N ₂ O生成机理的理解，但是由于缺乏在全尺寸系统中建立N ₂ O缓解策略的标准化方法，仍需要进一步的努力。挑战之一似乎是将反硝化过程从净N ₂ O源转换为有效的汇，在本次审查中建议将其作为减少N ₂ O产生的关键机会。