【摘要】 在西安市城市主干道南二环路建立路面径流原位采样站,利用自制流量等比例采样装置,对2009年3月—2010年2月的36场降雨径流和3场融雪径流进行全程采样,测试各场次径流SS、COD、溶解态COD、NH+4-N、Pb、溶解态Pb、Zn和溶解态Zn的事件平均质量浓度(EMC),结合径流污染来源,利用单因素方差分析方法,识别路面径流污染季节变化特征并进行致因分析。结果表明:路面径流中SS质量浓度、COD和NH+4-N质量浓度随季节变化显著,SS质量浓度和COD呈现冬、春季高、秋季最低的趋势,表明其受交通污染源排放和大气降尘的共同影响;NH+4-N质量浓度秋冬采暖季最高、夏季最低,且与雨水接近,表明其主要源于雨水溶解大气中的含氮化合物造成的雨水污染;Pb、Zn主要来自交通污染源,道路交通量不随季节变化,因此其质量浓度季节差异不大,场次间质量浓度的波动主要与场次降雨特征有关。更多还原

【Abstract】 The present paper is aimed at providing a detailed analysis of the seasonal variation characteristics of road runoff pollution in Xi’an area. As is known,urban road runoff is generally regarded as the second pollution source,which may bring about serious influence on the quality of urban water environment and therefore turns to be a well-accepted hot research topic since1970 s in the western countries. And,so is for China in recent years. We know that there are three kinds of pollution sources for the traffic road runoff,particularly,that is,the traffic pollution emission,the dustfall and the polluted rainfall. As a kind of nonpoint source pollution,road runoff pollution varies greatly with time and space. In this paper,we have collected and sampled our urban road runoff data from our accounting of 36 rainfall events and 3 snow events that took place on the south second ring road in Xi’an area by using a self-made volume proportionally collecting device from Mar. 2009 to Feb. 2010. For our research purpose,we have tested the event mean concentration( EMC) of SS,COD,dissolved COD,NH+4-N,Pb,dissolved Pb,Zn and the dissolved Zn. Joining the three sources of road runoff pollution together,we have studied the seasonal variation characteristics of the road runoff pollution with the one-way ANOVA method. The results of our study and analysis indicate that EMC of SS,COD and NH+4-N prove to be varied with the seasonal change significantly. For example,the concentrations of SS and COD prove to be significantly higher in winter and spring,but lowest in autumn.It becomes clear that the higher concentrations of SS and COD should be caused by the dustfall and traffic pollutant emission inseparably. At the same time,the NH+4-N concentration of the road runoff proves lowest in summer and highest in winter,which is close to the concentration of the rainfall. As to the heavy metals in the road runoff,such as Pb and Zn,they should be mainly attributed to traffic pollution sources. However,since the road traffic volume does not vary with the seasonal change,heavy metal concentrations tend to remain the same in spite of the change of the seasons in statistical sense. Nevertheless,a certain variation of the heavy metal concentration can be found between the rainfall events,which is mainly related to the features of the rainfall.更多还原