城市道路路面沉积物重金属污染程度评价

Evaluation of heavy metals pollution in urban road deposited sediments

以南京城区道路路面沉积物为研究对象,通过人工清扫采样、消解预处理和原子吸收分光光度计测量的方法对沉积物中重金属污染状况进行了分析。结果表明,道路路面沉积物中Cu、Cr、Zn、Pb、Mn、Cd、Ni的含量明显高于当地土壤环境背景值,其最大浓度值分别是土壤背景值的42.0、190.0、20.0、946.0、6.4、101.6和12.8倍。对路面沉积物中重金属单项污染指标的分析表明:研究区域路面沉积物中的单项重金属75%处于重度污染状态,5.55%处于中度污染状态,11.11%处于轻度污染状态,8.34%处于非污染状态。内梅罗污染综合评价指标分析结果表明:研究区域路面沉积物污染程度从大到小依次为机动车红绿灯处、机动车道、人行道、校园内、立体交叉道路和居民区。

Artificial cleaning method was used to sample the urban road sediments for analyzing its heavy metals pollution characteristics in various functional areas in Nanjing.The soil sample was pretreated by acid digestion method and the metal concentration was measured by atomic absorption spectrophotometer.The results showed that the contents of Cu,Cr,Zn,Pb,Mn,Cd,Ni in urban road deposited sediment were obviously higher than in the local soil environmental background values.Comparing to the soil background values of Jiangsu province,the maximum concentration of metal were 42.0,190.0,20.0,946.0,6.4,101.6 and 12.8 times,respectively.The single heavy metal pollution index of the road surface deposited sediments showed that： 75 % of the area was severe pollution,5.55 % was medium-polluted,and 11.11 % was light pollution,8.34 % was no pollution;Nemero index analysis results showed that： the road surface sediment pollution degree area from the most serious to slight in turn as follow： the motor vehicle traffic lights,motor lane,sidewalks,campus,overpass roads and residential areas.