通过采集和监测2010年雨季重庆市同一区域的2条不同材质公路的3次降雨径流过程水样,研究了沥青路面和水泥路面径流的污染特征和差异.结果表明,2种材质路面径流中化学需氧量(COD)、总氮(TN)和总磷(TP)的次降雨平均浓度(EMC)均超过国家地表水环境质量V类水质标准(GB3838—2002);沥青路面径流中总悬浮物(TSS)、COD和TP的浓度明显高于水泥路面,分别为水泥路面的2.05、1.35和1.27倍;沥青路面污染物的初始浓度普遍高于水泥路面,TSS和TP浓度最大值的出现时间滞后于水泥路面.在2010年6月19日、7月4日和7月9日的3场降雨事件中,沥青路面30%径流量与此时径流污染物浓度之比的平均值(FF30)分别为水泥路面的1.26、1.07和1.32倍.沥青路面坑槽较多和成分复杂是导致其表现出不同于水泥路面的径流污染特征的重要原因.
Runoff samples from two pavements with different materials during the three rain events in 2010 in Chongqing were collected and determined.The characteristics and differences of runoff pollution on asphalt pavement and concrete pavement were investigated.The results showed that the event-mean concentrations of chemical oxygen demand(COD),total nitrogen(TN) and total phosphorus(TP) exceeded the environmental quality standard of Class V surface water.The concentrations of total suspended substances(TSS),COD and TP from the runoff on asphalt pavement were 2.05,1.35 and 1.27 times higher than that on concrete pavement,respectively.The initial concentrations of pollutants on asphalt pavement were higher than those on concrete pavement,and the maximum concentrations of TSS and TP on asphalt pavement appeared later than those on concrete pavement.During the three rainfall events on June 19,July 4 and July 9 in 2010,the average values of the ratios of 30% runoff amount to the concentration of the pollutant in runoff(FF30) on asphalt pavement were 1.26,1.07 and 1.32 times that on concrete pavement,respectively.Differences in number of dents and chemical compositions of the pavements were the two major causes for the differences of runoff pollution.