高速公路雨水径流重金属污染特性研究  

Characteristics of Metals Pollution in Expressway Stormwater Runoff

作　　者：李贺[1] 石峻青[1] 沈刚[2] 季晓亮[2] 傅大放[1] 

机构地区：[1]东南大学市政工程系,南京210096 [2]江苏省长江公路大桥建设指挥部,南京210004

出　　处：《环境科学》2009年第6期1621-1625,共5页Environmental Science

基　　金：江苏省交通科技重大计划项目(TZ0761-010)

摘　　要：对南京机场高速公路路面径流中Cd、Cu、Pb和Zn这4种重金属进行了现场取样检测,重点探讨了重金属污染的出流规律、事件平均浓度(EMC),并分析了降雨特征对径流重金属污染的影响.结果表明,不同类型降雨事件重金属污染出流规律不同:降雨历时短、降雨量小、降雨强度小的降雨事件重金属浓度在一定范围内波动,在整个径流过程中始终维持在较高水平;降雨历时长、降雨量大、前期强度大的降雨事件初期污染物浓度高、污染重,初期效应显著;降雨历时短、降雨量较大具有双峰雨型的降雨事件中重金属出流存在"二次冲刷"现象.计算结果表明,Cd、Cu、Pb和Zn的EMC中值浓度分别为1.43μg.L-1、0.092 mg.L-1、38.6μg.L-1和0.51 mg.L-1.Pb总体污染程度较严重,Cd、Cu和Zn与国内同类研究相比污染程度较为接近.重金属浓度与降雨特征相关性分析表明,降雨量对Cu的溶解出流影响较大,前期晴天数对Zn在路面的积累影响较大.Heavy metal concentrations of Cd, Cu, Pb and Zn were monitored during 10 rainfall runoff events occurred on a representative expressway road in Nanjing. Discharge rule of metal pollution, event mean concentrations （EMC） and the effect of hydrologic characteristics were evaluated. The results indicated that the discharge characteristics were various in different types of rainfall events. The metal concentrations fluctuated in the range of comparatively high levels during the events with short duration, light rainfall and low intensity. In the events with long duration, heavy rainfall and initial high intensity, the initial metal concentrations were high and metal exhibited a pronounced first flush. Second flush effect existed in the events with short duration, medium rainfall and double intensity peaks. The EMCs of Cd, Cu, Pb and Zn were 1.43 μg·L^-1 , 0.092 mg·L^-1 , 38.6 μg·L^-1 and 0.51 mg·L^-1 , respectively. EMCs showed that the pollution extent of Pb was serious. Pollution of Cd, Cu and Pb were similar to other domestic reports, but Pb was lower than those studies. Cu and Zn were similar to related foreign studies, but Cd and Pb were lower. Correlation analysis suggested that the influence of rainfall on the discharge of Cu and the influence of antecedent dry period on the accumulation of Zn were significant.

关 键 词：路面径流 重金属 出流规律 事件平均浓度 

分 类 号：X734[环境科学与工程—环境工程]