合肥市经开区路面径流中重金属污染特征分析

Analysis of Characteristics of Heavy Metal Pollution in Road Rainfall-Runoff of Economic Development Distinct in Hefei

通过对合肥市经开区降雨期间路面径流中Cd、Cr、Cu、Mn、Pb等几种重金属监测,分析路面径流中重金属的平均含量、出流特征以及颗粒吸附态重金属含量与SS浓度的相关关系。结果表明,车流量较大的交通主干道的重金属含量远大于车流量小的校园道路,说明路面径流中重金属来源于汽车尾气的排放、轮胎的磨损等;重金属污染存在明显的初期冲刷效应。颗粒吸附态重金属与悬浮物浓度的相关性分析表明,颗粒吸附态重金属与悬浮物浓度相关性较大,重金属多吸附在悬浮物上或以重金属颗粒的形态存在。

For studying pollution characteristics of several heavy metals,including Cd,Cr,Cu,Mn,and Pb in road runoffs,during a rainfall event,contents and flow characteristics of heavy metals,the relationship between heavy metals and SS concentration in samples from Economic Development Distinct of Hefei were analyzed.The results showed that concentrations of heavy metals were far greater if those sampling sites lie near the main roads with heavier traffic loadings,which indicated some traffic factors such as vehicle exhaust emissions and worn tires may be the main sources of heavy metals in road runoff.The first flush effects of heavy metals were found obviously in the current rainfall event.By the correlation analysis,a strong relationship between most of heavy metals（Pb excluded） and suspended solids was obtained,and a great mass of heavy metals existed in the form of adsorption in suspended solids or heavy metal particles.