洪湖湿地-地下水系统中氮来源与转化过程的水化学和多同位素解析

To investigate how surface water-groundwater interactions influence the speciation and sources of nitrogen (N) in wetland-groundwater systems, this study focuses on the Honghu Lake wetland, and utilizing groundwater flow direction, hydrochemical methods and stable isotopes to demonstrate the speciation, sources and transformation of N in the wetlandgroundwater system.The results indicate that nitrate and ammonium are the primary species of N in surface water and groundwater, respectively.Nitrate in surface water mainly originates from external river inputs, while ammonium in groundwater may result from organic matter degradation or autotrophic nitrate reduction to ammonium (DNRA), with the latter being the predominant source.Eutrophic lake water-groundwater interactions can introduce nitrate into groundwater 基金项目： 湖北省自然科学基金项目 (No.