This work reviews applications of stable isotope analysis to the studies of transport and transformation of N species in groundwater under agricultural areas. It summarizes evidence regarding factors affecting the isotopic composition of NO₃⁻, NH₄⁺ and N₂O in subsurface, and discusses the use of ¹¹B, ¹⁸O, ¹³C, ³⁴S, ⁸⁷Sr/⁸⁶Sr isotopes to support the analysis of δ¹⁵N values. The isotopic composition of NO₃⁻, NH₄⁺ and N₂O varies depending on their sources and dynamics of N cycle processes. The reported δ¹⁵N-NO₃⁻ values for sources of NO₃⁻ are: soil organic N – + 3‰–+8‰, mineral fertilizers – − 8‰–+7‰; manure/household waste – + 5‰ to + 35‰. For NH₄⁺ sources, the isotopic signature ranges are: organic matter – + 2.4–+4.1‰, rainwater – − 13.4–+2.3‰, mineral fertilizers – − 7.4–+5.1‰, household waste – + 5–+9‰; animal manure – + 8–+11‰. For N₂O, isotopic composition depends on isotopic signatures of substrate pools and reaction rates. δ¹⁵N values of NO₃⁻ are influenced by fractionation effects occurring during denitrification (ɛ = 5–40‰), nitrification (ɛ = 5–35‰) and DNRA (ɛ not reported). The isotopic signature of NH₄⁺ is also affected by nitrification and DNRA as well as mineralization (ɛ = 1‰), sorption (ɛ = 1–8‰), anammox (ɛ = 4.3–7.4‰) and volatilization (ɛ = 25‰). As for the N₂O, production of N₂O leads to its depletion in ¹⁵N, whereas consumption – to enrichment in ¹⁵N. The magnitude of fractionation effects occurring during the considered processes depends on temperature, pH, DO, C/NO₃⁻ ratio, size of the substrate pool, availability of electron donors, water content in subsoil, residence time, land use, hydrogeology. While previous studies have accumulated rich data on isotopic composition of NO₃⁻ in groundwater, evidence remains scarce in the cases of NH₄⁺ and N₂O. Further research is required to consider variability of δ¹⁵N-NH₄⁺ and δ¹⁵N-N₂O in groundwater across agricultural ecosystems.

这项工作回顾了稳定同位素分析在农业地区地下水中N物种迁移和转化研究中的应用。它总结证据就影响NO的同位素组成因素₃ ^-，NH ₄ ⁺和N ₂ ○在地下，并讨论了使用¹¹ B，¹⁸ O，¹³ C，³⁴ S，⁸⁷ SR / ⁸⁶锶同位素，以支持δ的分析¹⁵的N值。NO的同位素组成₃ ^-，NH ₄ ⁺和N ₂O根据其来源和N个循环过程的动力学而变化。所报告的δ ¹⁵ N-NO ₃ ^-为NO的来源的值₃ ^-有：土壤有机N - +  3‰ - + 8‰，矿物肥料- -  8‰ - + 7‰; 粪便/家庭垃圾– +  5‰至+  35‰。对于NH ₄ ⁺源，同位素特征范围为：有机物– +  2.4– + 4.1‰，雨水– −  13.4– + 2.3‰，矿物肥料– −  7.4– + 5.1‰，生活垃圾– +  5– + 9‰ ; 动物粪便– +  8– + 11‰。对于N ₂ O，同位素组成取决于底物库的同位素特征和反应速率。δ ^15个NO的N个值₃ ⁻受反硝化（ɛ  =  5–40‰），硝化作用（ɛ  =  5–35‰）和DNRA（ɛ未报道）期间发生的分馏效应的影响。NH ₄ ⁺的同位素特征还受硝化和DNRA以及矿化作用（ɛ  =  1‰），吸附作用（ɛ  =  1–8‰），厌氧氨氧化作用（ɛ  =  4.3–7.4‰）和挥发作用（ɛ  =  25 ‰）。至于N ₂ O，N ₂ O的产生导致其消耗¹⁵ N，而消耗–导致其富集¹⁵N的期间所考虑的过程中发生分馏效应的大小取决于温度，pH，DO，C / NO ₃ ^-比，基底池的大小，电子供体的可用性，在底土含水量，停留时间，土地使用，水文。虽然以前的研究已经积累了NO的同位素组成丰富的数据₃ ^-地下水，证据NH的情况下仍然较少₄ ⁺和N ₂ O.进一步的研究来考虑δ变化需要¹⁵ N-NH ₄ ⁺和δ ¹⁵ NN ₂ Ø在整个农业生态系统的地下水。