九龙江河流-河口连续体氮素的主要去除过程及N_(2)O排放特征

Typical nitrogen removal and N_(2)O emission features in river-estuary continuum of the Jiulong River

我国东南沿海地区人口密集,生活污水排放量大,同时农业活动中氮肥施用过量,这些因素导致近年来河流-河口连续体氮负荷显著上升,威胁水生生态系统安全.此外,由于河口、支流、干流水文环境差异大,在外源氮输入胁迫下水生生态系统中氮的迁移转化过程也愈加复杂.本文总结了我国东南沿海地区典型流域九龙江的氮素相关研究,通过分析九龙江支流、干流、河口水体中溶解性无机氮的空间差异,解析反硝化及厌氧氨氧化这两类主要氮去除反应的强度及其在耦合条件下对N_(2)和N_(2)O排放通量的影响.在此基础上,探讨九龙江河流-河口连续体的氮去除过程及通量变化,为我国流域氮循环理论的完善及水体富营养化的防治提供参考.

The Southeast of China is densely populated,and great domestic sewage discharge and excessive nitrogen fertilizer application in agricultrure lead to a significant increase in the nitrogen loading in river-estuary continuum,threating the safety of aquatic ecosystem.Besides,the water environments of estuary,tributary and main stream are quite different,which leads to a complex nitrogen transport and transformation in the aguatic ecosystem.In this review,recent studies on the nitrogen related to the Jiulong River in the Southeast of China are summarized.By analyzing the spatial difference of dissolved inorganic nitrogen(DIN)in the tributary,main stream and estuary of the Jiulong River,the reaction intensities of denitrification and anammox processes are elucidated,and the N_(2)and N_(2)O emission affected by the coupled anammox-denitrification is also clear.Finally,the nitrogen removal and flux variation in the river-estuary continuum of the Jiulong River are summarized.This review provides references for the improvement of nitrogen cycle theory and the prevention and control of water eutrophication in small basins of China.