氮氧稳定同位素技术用于水体中硝酸盐污染来源解析方面的研究进展

Identification of nitrate source in receiving water with dual \rmNO_3^- isotopes (δ(15N) and δ(18O))

  • 摘要: 在总结不同硝酸盐潜在污染源的氮氧同位素特征值基础上,对可能使溯源结果产生影响的同化作用、反硝化作用以及硝化作用的判别方法进行了介绍.通过对文献中氮(δ15N))氧(δ18O))同位素特征值进行整理,发现随着时间以及地域的跨度增加,δ(15N)和δ(18O)的特征值范围也不断增加,这导致特征值区间彼此重叠,从而并不利于溯源的进行.此外,通过δ(18O)与δ(15N)值可直观反映相关反应的发生,但是在某些情况下,同化作用与反硝化作用可能无法区分,而硝化作用产生的δ(18O)值也并非唯一.在总结氮氧稳定同位素技术解析硝酸盐污染来源的基础上,尝试对未来的发展方向提出建议.

     

    Abstract: Impacts of nitrate pollution on environment and on human health have attracted widespread attention.Accurate analysis of the sources of nitrate can effectively manage nitrate pollution.The dual \rmNO_3^- stable isotopes technology is relatively simple and accurate, and it has been widely used in the analysis of nitrate sources in surface water and groundwater.The eigenvalues of nitrogen (δ(15N)) and oxygen (δ(18O)) isotopes of potential sources were used here to identify assimilation, denitrification and nitrification that may affect traceability results.Relavant literature search indicates that eigenvalues increase with increasing temporal and spatial scales, leading to overlap of eigenvalues, which are not conducive to source traceability.In addition, δ(18O) values and δ(15N) values could directly reflect occurrence of related reactions.But in some cases, assimilation and denitrification may not be distinguished, and δ(18O) values produced by nitrification may not be unique.The current method for nitrate source analysis is well-accepted, but assurance of integrity and non-overlapping of nitrate sources is a prerequisite for accurate source quantification.Therefore, with application of δ(15N) and δ(18O) technology to source analysis of nitrate in lakes, we give some suggestions for future research.

     

/

返回文章
返回