生态雨水设施的污染物积累效应及风险研究进展

对植被浅沟、雨水花园及雨水塘3种具有代表性的生态雨水设施应用于径流中有机质、颗粒物、重金属等污染物控制时,污染物在设施内的积累特性进行了归纳总结,分析了设施长期运行时面临的污染风险,提出了这3种生态雨水设施运行管理与维护的建议:植被浅沟运行寿命应结合我国道路雨水径流水质综合确定,超期运行的植被浅沟应对表层5cm种植土进行更换;雨水花园表层介质重金属含量较高时,可更换0~10 cm深度范围内的种植土,为减少表层磷溶出量,可在表层覆盖树皮以加强对磷的吸附;雨水塘中沉积物的清理周期应按功能区分类确定,对于沉积物中多环芳烃含量较高的干塘应酌情增加清理次数。

Pollutant accumulation effect and risk to ecological rainwater facilities

This paper reviews progress in research on the pollution accumulation in and long term risk to ecological rainwater facilities such as grass swales, rain gardens, and stormwater ponds, which are used to control runoff pollutants such as organics, suspended solids, and heavy metals. Suggestions are given for the operation and maintenance of these three types of facilities: the service life of grass swales should be regulated according to the runoff water quality in China, and the top 5 cm soil of grass swales should be replaced when they exceed the limit of the service life; 0 to 10 cm of soil should be replaced when there are high levels of heavy metal in the media, and bark mulch is an effective way to prevent the leaching of phosphorous from the top soil due to its phosphorus adsorption ability; the dredging cycle should be determined according to where the function areas in the pond are located, and the dredging frequency of a dry pond could be discretionarily increased due to the higher concentration of PAH in its sediment.