北京城市道路地表径流中PAHs的污染特征研究

以北京城市道路地表径流中的PAHs为研究对象,于2006年雨季在海淀区成府路和海淀路设置3个采样点采集了6场地表径流和同期雨水样品,分析了溶解相和颗粒相PAHs的浓度.对地表径流和雨水样品中PAHs的浓度特征,地表径流中PAHs在时间和空间上的变化,及辅助参数的相关性进行了探讨.结果表明,海淀路地表径流EMC值大于成府路,自行车道地表径流EMC值与机动车道相近,道路地表径流PAHs的污染程度不能仅根据车流量判断.对单场径流历时中PAHs浓度变化的分析和累积污染负荷曲线的研究均表明,道路径流初期冲刷效应并不是普遍发生的,而是受路面积尘特征和降雨条件等多种因素的影响.

Study on PAHs concentrations in urban road runoff in Beijing

Road runoff and rainwater samples were collected at 3 sampling sites at Chengfu Road and Haidian Road in Beijing during the rainy season of 2006. The samples were analyzed for PAHs in both particle and dissolved phases. The variations of PAH concentrations among different sampling sites and storm events, and the relationship between PAHs and auxiliary parameters were investigated. PAHs concentrations in storm runoff water at Haidian Road were generally larger than at Chengfu Road, and the concentration in the bicycle lane was as high as that in the roadway. This result shows that PAHs contamination in road runoff cannot be judged only by traffic volume (motorcycles use the roadway according to field investigation). Analysis of temporal changes of PAHs concentration and loading indicated that the occurrence of first flush events depends on multiple factors including features of the road dust and type of rainfall.