土壤是N₂O的重要排放来源之一。土壤中N₂O产生途径众多、受多种因素调控，深入分析土壤N₂O产生途径才能采取针对性的减排策略。稳定同位素技术已广泛用于研究土壤N₂O排放，N₂O同位素异位体法是近年来新兴的研究方法。该研究方法通过测定土壤N₂O的同位素组成（δ¹⁵N^SP_N2O、δ¹⁸O_N2O和δ¹⁵N^bulk_N2O）分析N₂O排放贡献，因无需添加标记物、对土壤系统干扰小、成本低，适合在野外田间研究N₂O排放，是¹⁵N标记方法的有力补充。本文详细介绍了N₂O同位素异位体法的原理、质谱测定方法、定量分析方法、影响该方法的因素及其应用前景。

Soil is one of the important sources of N₂O emissions. Soil N₂O production pathway is numerous and regulated by variety of factors, in-depth analysis of soil N₂O production pathway can adopt targeted emission reduction strategies. Stable isotope technology has been widely used to the study of soil N₂O emissions, N₂O isotope method is an emerging research method in recent years. This method analyzes N₂O emission contribution by measuring the isotope composition of soil N₂O (δ¹⁵N^SP_N2O, δ¹⁸O_N2O and δ¹⁵N^bulk_N2O), because not need to add markers, little interference to soil system and low in cost, it is suitable for field research on N₂O emissions and is a powerful supplement to ¹⁵N labeling method. This paper introduces in detail the principle of N₂O isotope method, mass spectrometry method and quantitative analysis method, the factors affecting the method and its application prospect.

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国家自然科学基金面上项目（41977084）资助。