镇江城市降雨径流营养盐污染特征研究

城市降雨径流污染是城市水体水质恶化的主要原因之一,为了分析降雨径流的污染特征,从2006-05开始,选择镇江具有代表性的土地使用功能对其降雨径流水质进行监测,分析了径流中固体悬浮物和营养盐的变化特征.结果表明,镇江不同功能区中5～40 μm粒径的固体悬浮物体积分数最大;商业区径流污染物浓度很高,其中SS浓度高达978 mg/L,是城市面源污染的主要来源;降雨初期的30 min径流污染物浓度很高,随降雨历时的延长污染物浓度逐渐下降并趋于稳定;溶解态氮、颗粒态磷和固体悬浮物是径流中污染物输出的主要形态;通过分析固体悬浮物与其他污染物的相关性,发现固体悬浮物是径流中营养盐吸附的载体,去除固体悬浮物是治理镇江降雨径流污染的有效途径.

Nutrients of Urban Stromwater Runoff in Zhenjiang

Urban stormwater pollution is recognized as one of the major causes of water quality deterioration in the receiving water bodies. Starting in May 2006, a study was conducted to characterize water quality from representative land uses types in Zhenjiang. By analyzing the varieties of suspended solids (SS) and nutrients, the results show that the 5-40 microm size class dominates in all the samples, and urban stormwater pollution mainly results from commercial area where concentrations of pollutants are so high that concentration of SS reaches 978 mg/L. Concentrations of pollutants in initial flush are very high, and they descend sharply along with the time to reach the stable stage. The main phases of pollutants discharge are dissolved nitrogens, particle phosphorus and SS. Analysis of correlation of SS and other pollutants finds that SS are the absorbed carrier of nutrients from urban stormwater runoff, and removal of SS is the effective way to control urban stormwater pollution in Zhenjiang.