College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China; College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China.
Sci Total Environ. 2021 Mar 25;762:144168. doi: 10.1016/j.scitotenv.2020.144168. Epub 2020 Dec 17.
The Earth is experiencing excessive nitrogen (N) input to its various ecosystems due to human activities. How to effectively and efficiently remove N from ecosystems has been, is and will be at the center of attention in N research. Hyporheic and riparian zones are widely acknowledged for their buffering capacity to reduce contaminants (especially N) transport downstream. However, these zones are usually misunderstood that they can remove N at all spots and at any moments. Here pathways of N removal from hyporheic and riparian zones are reviewed and summarized with an emphasize on their hot spots and hot moments. N is biogeochemically removed by denitrification, anammox, nitrifier denitrification, denitrifying anaerobic methane oxidation, Feammox and Sulfammox. Hot moments of N removal are mainly triggered by precipitation, fire and snowmelt. Finally, some research needs are outlined and discussed, such as developing approaches for multiscale sampling and monitoring, quantifying the effects of hot spots and hot moments at hyporheic and riparian zones and evaluating the impacts of human activities on hot spots and hot moments, to inspire more research on hot spots and hot moments of N removal. By this review, we hope to bring awareness of the heterogeneity of hyporheic and riparian zones to catchment managers and policy makers when tackling N pollution problems.
由于人类活动，地球的各种生态系统正经历着过度的氮（N）输入。如何有效地从生态系统中去除 N，一直是、现在是、将来也仍然是 N 研究的焦点。渗流区和河岸带由于其缓冲能力而被广泛认为可以减少污染物（尤其是 N）向下游的输送。然而，这些区域通常被误解为可以在任何地点和任何时刻去除 N。本文综述了从渗流区和河岸带去除 N 的途径，并重点介绍了它们的热点和高峰时刻。N 通过反硝化、厌氧氨氧化、硝化反硝化、厌氧甲烷氧化、铁氨氧化和硫氨氧化等生物地球化学过程被去除。N 去除的高峰时刻主要是由降水、火灾和融雪触发的。最后，本文还概述和讨论了一些研究需求，例如开发多尺度采样和监测方法、量化渗流区和河岸带热点和高峰时刻的影响以及评估人类活动对热点和高峰时刻的影响，以激发更多关于 N 去除热点和高峰时刻的研究。通过本文的综述，希望在处理 N 污染问题时，让集水区管理者和决策者意识到渗流区和河岸带的异质性。
