滨河湿地对农业非点源氮污染控制研究进展

氮素是农业径流最重要、最普遍的水体污染物。滨河湿地因受到陆地生境和水生生境双重影响而显得非常独特，作为重要的陆地和水生环境的生态交错带，滨河湿地能够阻断和改变水运污染物，特别是农业径流中的氮排入临近的小溪和河流。植物吸收和反硝化作用是滨河湿地两种最重要的截留和缓解氮负荷的有效途径，氮素可以通过生物转化、植物吸收、微生物暂时固氮等方式去除，但是永久性的去除氮却是通过反硝化过程来完成的。为了系统认识和了解滨河湿地生态系统对农业非点源氮污染控制过程，通过大量文献分析讨论了滨河湿地对农业非点源氮的净化能力、净化机制及其影响因素，并结合我国研究现状展望了该领域的研究前景。滨河湿地对农业非点源氮污染的控制作用研究将成为滨河湿地生态系统服务功能评价、滨河湿地生态系统健康与稳定的诊断和退化滨河湿地生态系统修复的重要基础理论。

Research progress in agricultural non-point nitrogen pollution control in riparian wetlands

Nitrogen is considered as the most important and widespread water pollutant in agricultural runoff. The riparian landscape is unique among environments because it is a terrestrial habitat strongly affecting and affected by aquatic environments. As important ecological ecotones between terrestrial and aquatic environments, riparian wetlands can intercept and transform water borne pollutants, especially N in runoff from agricultural land before discharging into adjacent streams or rivers. Plant uptake and denitrification are considered to be the most important processes responsible for N retention and mitigation in riparian wetland. Nitrogen in wetlands is removed from the water by biological transformations, plant uptake and microbes temporarily immobilize nitrogen, whereas permanent nitrogen removal occurs via denitrification. In order to comprehend the nitrogen control effect of riparian wetland on agricultural ecosystem, the nitrogen removing function, mechanism and the influencing factors of denitrification process were analyzed on the basis of a lot of references. And the foreground of the research area was prospected after summarizing the present study state in our country. This research area will become important basic theory of ecosystem service evaluation, ecosystem health and stabilization degradation restoration in riparian wetlands.