太湖沉积物重金属污染生态风险的综合评价

为研究太湖沉积物重金属污染的生态风险。在2012年2月采集太湖7个采样点的表层沉积物,分析测定重金属总量以及可交换态和碳酸盐结合态的金属含量,采用风险评价准则、潜在生态风险指数法对沉积物重金属污染进行生态风险评价。结果表明:太湖沉积物中重金属除竺山湾处于偏中度污染水平,其他各点均处于轻度污染状态。全湖Ni、Zn和Cu的可利用态比例较高。太湖沉积物重金属污染为低生态风险,竺山湾生态风险高于其他地区。Ni和Pb的生态风险高于其他金属。需对太湖竺山湾污染物排放进行控制,对全湖沉积物中Ni污染进行优先控制与去除。

Comprehensive Evaluation of Ecological Risk of Heavy Metal Pollution in the Surface Sediments of Taihu Lake

The study is aimed at assessing the ecological risks of heavy metal pollution in the surface sediments of Taihu Lake.In February 2012,surface sediments were collected from 7 sampling sites in Taihu Lake for measurement of the total amount of heavy metals and the content of the metals exchangeable and carbonate-bound.Risk assessment code and potential ecological risk index were used for the assessment.The results showed that heavy metal pollution in the sediments at Zhushan Bay of Taihu Lake was in a moderate pollution level but were in a light pollution level at other regions.The bio-available fractions of Ni,Zn and Cu were higher than other metals in the whole lake.The overall ecological risk of heavy metal pollution in Taihu Lake was low.However,the ecological risk at Zhushan Bay was higher.The ecological risk of Ni and Pb were higher than other metals.It is recommended that pollutant discharge into Zhushan Bay should be controlled and Ni contamination in the sediments of the whole lake should be given priority for control and removal.