黄浦江表层沉积物中重金属污染的潜在生态风险评价

采用潜在生态风险指数法对黄浦江表层沉积物中重金属污染的潜在生态风险进行了评价。评价结果表明，黄浦江表层沉积物中重金属的潜在生态风险水平较低，其中杨浦大桥和南市水厂断面达到中等生态风险，其它断面均为轻微生态风险；重金属的潜在生态风险依次为Cd>Hg>Cu>As>Pb>Cr>Zn，除Cd达到中等生态风险外，其余元素均为轻微生态风险。沉积物中重金属的污染水平从上游到下游呈上升趋势，工业排放是水环境中重金属的主要来源，苏州河对黄浦江下游重金属存在一定的输入贡献。相关性分析表明，黄浦江表层沉积物中大多数重金属元素呈现相近的来源特征，有机质是影响沉积物中重金属分布的重要因素。

EVALUATION ON POTENTIAL ECOLOGICAL RISK OF HEAVY METAL POLLUTION IN SURFACE SEDIMENTS FROM HUANGPU RIVER

The ecological risk of heavy metal pollution in surface sediments in Huangpu River was studied with potential ecological risk index. The results showed that potential ecological risk of heavy metals in surface sediments from Huangpu River was a bit low,with middle ecological risk at Yangpu Bridge section and Nanshi Water Work section,and low ecological risk at other sections. Potential ecological risk of heavy metals decreased as:Cd>Hg>Cu>As>Pb>Cr>Zn. Cd was the most hazardous element with the mean ecological risk index of 30. 96,which belonged to middle ecological risk,and other elements belonged to low ecological risk. The pollution level of heavy metals increasing from upper to downstream of Huangpu River implicated that discharging of industrial effluents was the most important source for heavy metals in Huan- gpu River,and inflow of Suzhou River offered lots of heavy metals to downstream of Huangpu River. Cor- relation analysis showed that most of heavy metals came from similar sources,and organic matter content influenced the distribution of heavy metals in sediment strongly.