环渤海典型海域潮间带沉积物中重金属分布特征及污染评价

对环渤海11个采样点潮间带沉积物中重金属含量进行了测定,结果表明:Cu、Cr、Zn、As、Cd、Pb的平均含量分别为14.92,31.73,73.68,11.34,0.448,21.94 mg · kg^-1.与国内典型的河口和海湾比较,Cu、Cr、Zn、As处于相对较低水平,Cd、Pb处于中等水平.重金属表现出相似的空间变化规律,即高值区集中在辽东湾,次高值区在渤海湾,低值区位于莱州湾.相关性分析表明:Cr、Cu、Zn、Cd、Pb可能具有相似的输入源,As的主要来源可能与其它几种金属不同.地累积指数法评价结果显示:Cr、Cu、Zn、As属于清洁级别,Pb处于轻度污染水平,Cd处于偏中度污染.重金属元素污染程度排序为Cd>Pb>Zn>Cu>As>Cr.潜在生态危害指数法评价结果表明:重金属对渤海典型海域生态风险构成的危害程度排序为Cd>Pb>As>Cu>Zn>Cr.Cr、Cu、Zn、As、Pb均为低生态危害等级,Cd以中等生态危害等级为主,局部海域出现强、很强、极强生态危害等级.

Distribution and pollution assessment of heavy metals in sediments from typical areas in the Bohai Sea

The content of heavy metals in sediments from 11 sampling sites in the intertidal zone around the Bohai Sea was examined.The average contents were 14.92 mg · kg^-1 Cu, 31.73 mg · kg^-1 Cr, 73.68 mg · kg^-1 Zn, 11.34 mg · kg^-1 As, 0.448 mg · kg^-1 Cd and 21.94 mg · kg^-1 Pb.Compared to typical estuaries and bays in China, the content of Cu, Cr, Zn, As is relatively low, and the content of Cd, Pb is at a moderate level.All measured heavy metals presented a similar spatial variation, that is: their contents in the sediment of Liaodong bay> Bohai bay>Laizhou bay.Correlation analysis indicated that Cr, Cu, Zn, Cd, and Pb may have a similar input source but As may have a different source from other metals.The assessment by Geoaccumulation Index indicates that Cr, Cu, Zn, and As are at the unpolluted level, Pb at the slightly polluted level, Cd at the slightly-moderately polluted level.The pollution level of the heavy metals is: Cd>Pb>Zn>Cu>As>Cr.The assessment by the Potential Ecological Risk Index indicates that the potential ecological risk of typical areas in Bohai Sea caused by heavy metals is: Cd>Pb>As>Cu>Zn>Cr.The potential ecological risk of Cr, Cu, Zn, As, Pb is at the low level, and Cd is generally at the moderate risk level but it presents high or extremely high risk level in some parts of the sea.