雨水硝酸盐同位素研究现状及展望

The progress and prospect of nitrate stable isotopes in rainwaters

全球范围内高含量的氮沉降不但与酸雨有关,而且也改变了地表附近氮循环,为此控制大气中硝酸盐排放,确定大气中硝酸盐的来源以及研究氮的循环过程就显得尤为重要。由于在不同成因下,硝酸盐的δ^(15)N和δ^(18)O存在着差异,因此利用氮、氧同位素方法研究大气硝酸盐问题正日益受到国内外研究人员的重视。本文回顾了利用硝酸盐中氮、氧同位素来研究大气中硝酸盐的不同来源(火电厂排放、汽车尾气、闪电固氮、农业源等)和示踪其地球化学循环过程,并针对目前该研究中存在的问题,提出一些今后值得重视的研究方向。

The increasing nitrate concentration not only results in the acid rain, but also changes the nitrogen cycle around the surface in the world. Differentiation of various nitrate sources and knowledge of nitrogen cycling processes occurring in atmosphere are very important to establish suitable methods for controlling nitrate pollution. Since δ^15N and δ18O values vary in different sources of nitrate, more and more researchers attach great importance to the application of nitrogen and oxygen isotopes in atmosphere nitrate studies. This review summarizes recent trends in the study of distinguishing different sources of nitrate （coal-fired power plants, tailpipe exhaust, lightning, agriculture, etc. ） and tracing nitrogen cycling processes. The review also proposes some prospects for further studies.