Soils are sources of the potent greenhouse gas nitrous oxide (N₂O) globally, but emissions from permafrost-affected soils have been considered negligible owing to nitrogen (N) limitation. Recent measurements of N₂O emissions have challenged this view, showing that vegetated soils in permafrost regions are often small but evident sources of N₂O during the growing season (~30 μg N₂O–N m⁻² day⁻¹). Moreover, barren or sparsely vegetated soils, common in harsh climates, can serve as substantial sources of N₂O (~455 μg N₂O–N m⁻² day⁻¹), demonstrating the importance of permafrost-affected soils in Earth’s N₂O budget. In this Review, we discuss N₂O fluxes from subarctic, Arctic, Antarctic and alpine permafrost regions, including areas that likely serve as sources (such as peatlands) and as sinks (wetlands, dry upland soils), and estimate global permafrost-affected soil N₂O emissions from previously published fluxes. We outline the below-ground N cycle in permafrost regions and examine the environmental conditions influencing N₂O dynamics. Climate-change-related impacts on permafrost ecosystems and how these impacts could alter N₂O fluxes are reviewed, and an outlook on the major questions and research needs to better constrain the global impact of permafrost N₂O emissions is provided.

土壤是全球范围内强大的温室气体一氧化二氮（N ₂ O）的来源，但是由于氮（N）的限制，永久冻土影响的土壤中的排放量可以忽略不计。最近对N ₂ O排放的测量挑战了这一观点，表明多年冻土区的植被土壤通常很小，但是在生长季节（〜30μgN ₂ O–N m ^-2天^-1）是N ₂ O的明显来源。此外，在恶劣气候下常见的贫瘠或稀疏的植被土壤可以作为N ₂ O的重要来源（约455μgN ₂ O–N m ^-2天^-1），证明了受永久冻土影响的土壤在地球N ₂ O预算中的重要性。在这篇综述中，我们讨论了来自北极，北极，南极和高山多年冻土地区的N ₂ O通量，包括可能作为源（例如泥炭地）和汇（湿地，旱地土壤）的区域，并估算了受全球永久冻土影响的区域。先前公布的通量导致土壤N ₂ O排放。我们概述了多年冻土区的地下N循环，并研究了影响N ₂ O动态的环境条件。与气候变化有关的永冻土生态系统影响以及这些影响如何改变N ₂审查了O通量，并提供了对主要问题和研究需求的展望，以更好地限制永久冻土N ₂ O排放的全球影响。