氮循环过程的微生物驱动机制研究进展

氮循环在生物地球化学中具有重要地位，与人类生活密切相关。氮循环在很大程度上依赖微生物驱动的氮素转化，而在转化过程中必然会造成不同形式氮的同位素效应。为更好地了解和溯源氮循环过程，本文从氮循环的物质通量、微生物作用及氮同位素效应等角度进行系统地论述，并对氧化亚氮 (N₂O) 分子内的特异同位素值区分微生物过程做了详细介绍。结果表明，人为固氮是环境中活性氮增加的主要原因，也进一步促进了氮素转化的各个环节。通过解析氮素循环中微生物过程的形成机理和评估每个过程的同位素效应，为进一步探索微生物的功能基因和氮素同位素效应的内在联系提供依据，对阐明氮循环过程中微生物驱动的分子机制具有重要意义，而两者的结合也为解决自然条件下氮素转化各过程的溯源难题指明了方向，也将成为今后研究的热点，并在揭示氮素转化机制中发挥越来越大的作用。

Advances in the mechanism of microbe-driven nitrogen cycling

Nitrogen cycle plays an important role in the discipline of biogeochemistry and is closely related to human life. Nitrogen cycle is largely dependent on microbe-driven nitrogen transformation, which inevitably results in isotopic effects of different forms of nitrogen. In order to better understand and trace the nitrogen cycle, this paper made a comprehensive summary from the material flux of nitrogen cycle, the microbial processes and the nitrogen isotope effects of nitrogen transformation processes, and the specificity of nitrous oxide (N₂O) molecule on distinguishing microbial processes. The results show that artificial nitrogen fixation is the main reason for the increase of active nitrogen in the environment, and also promoted the various links of nitrogen conversion. By analyzing the formation mechanisms of microbial processes in the nitrogen cycle and assessing the isotope effect of each process, it provides a basis for further exploring the internal connection between the functional genes and nitrogen isotope effects. It is important to elucidate the molecular mechanism of microbe-driven nitrogen cycle. The combination of the two methods also points out the direction for solving the source problem of nitrogen conversion processes under natural conditions, which is bounds to become the focus of future research and plays an increasingly important role in revealing the mechanism of nitrogen conversion.