Biswal Basanta Kumar, Vijayaraghavan Kuppusamy, Adam Max Gerrit, Lee Tsen-Tieng Daryl, Davis Allen P, Balasubramanian Rajasekhar
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.
Centre for Urban Greenery and Ecology, National Parks Board, Singapore, Singapore.
Crit Rev Biotechnol. 2022 Aug;42(5):713-735. doi: 10.1080/07388551.2021.1969888. Epub 2021 Sep 5.
Excess nitrogen in stormwater degrades surface water quality eutrophication and related processes. Bioretention has been recognized as a highly effective low-impact development (LID) technology for the management of high runoff volumes and reduction of nitrogen (N) pollutants through various mechanisms. This paper provides a comprehensive and critical review of recent developments on the biological N removal processes occurring in bioretention systems. The key plant- and microbe-mediated N transformation processes include assimilation (N uptake by plants and microbes), nitrification, denitrification, and anammox (anaerobic ammonia oxidation), but denitrification is the major pathway of permanent N removal. Overall, both laboratory- and field-scale bioretention systems have demonstrated promising N removal performance (TN: >70%). The phyla and are the most abundant microbial communities found to be enriched in biofilter media. Furthermore, the denitrifying communities contain several functional genes (e.g., /, and ), and their concentrations increase near the surface of media depth. The N removal effectiveness of bioretention systems is largely impacted by the hydraulics and environmental factors. When a bioretention system operates at: low hydraulic/N loading rate, containing a saturation zone, vegetated with native plants, having deeper and multilayer biofilter media with warm climate temperature and wet storm events periods, the N removal efficiency can be high. This review highlights shortcomings and current knowledge gaps in the area of total nitrogen removal using bioretention systems, as well as identifies future research directions on this topic.
雨水径流中的过量氮会降低地表水水质，引发富营养化及相关过程。生物滞留池已被公认为一种高效的低影响开发（LID）技术，可通过多种机制管理高径流量并减少氮（N）污染物。本文对生物滞留系统中发生的生物脱氮过程的最新进展进行了全面且批判性的综述。关键的植物和微生物介导的氮转化过程包括同化作用（植物和微生物吸收氮）、硝化作用、反硝化作用和厌氧氨氧化作用（厌氧氨氧化），但反硝化作用是氮永久去除的主要途径。总体而言，实验室规模和现场规模的生物滞留系统均展现出了良好的脱氮性能（总氮：>70%）。变形菌门和拟杆菌门是在生物滤池介质中发现的最丰富的微生物群落。此外，反硝化群落包含几个功能基因（例如，/、和），并且它们在介质深度表面附近的浓度会增加。生物滞留系统的脱氮效果在很大程度上受到水力和环境因素的影响。当生物滞留系统在低水力/氮负荷率下运行，包含饱和区，种植本地植物，拥有更深且多层的生物滤池介质，气候温暖且有湿润暴雨事件时，脱氮效率会很高。本综述强调了在使用生物滞留系统进行总氮去除领域的缺点和当前知识空白，并确定了该主题未来的研究方向。
