东山湾巴非蛤养殖区海水、沉积物重金属的含量分布与潜在生态危害评价

The Contents and Distributions and Potential Ecological Risk Assessment of Heavy Metals in Sea Water and Sediment from the Paphia undulata Culture Areas of Dongshan Bay

2003年5月、8月和10月对东山湾巴非蛤养殖区环境状况进行调查,根据调查资料,分析了巴非蛤养殖区海水、表层沉积物中Cu、Pb、Cd、Zn的含量分布,并进行生态环境质量评价及潜在生态危害评价。结果表明:东山湾巴非蛤养殖区海水中Cu、Pb、Cd、Zn的平均含量分别为1．75μg·L^(-1), 1．69μg．L^(-1),0．02μg．L^(-1),2．84μg．L^(-1),其季节变化从高到低依次为10月＞8月＞5月;沉积物中Cu、Pb、Cd、Zn的平均含量分别为14．0mg．kg-1、34．8mg．kg^(-1)、0．031mg．kg^(-1)、97．5mg．kg^(-1)。生态质量评价结果表明,养殖区海水重金属的含量符合第二类海水水质标准要求,处于清洁水平。养殖区沉积物重金属的含量符合第一类海洋沉积物质量标准,属于较清洁水平。生态危害评价表明,Pb和Cd的潜在生态危害系数大于Cu和Zn,但整个养殖区沉积物中重金属的潜在危害属于轻微,养殖环境良好。

Based on the research data of environmental survey for the Paphia undulata culture areas of Dongshan Bay in May, August and October, 2003, we analyzed the contents and distributions of Cu, Pb, Cd, Zn in seawater and surface sediments. Environmental quality and potential ecological risk assessment were also assessed in this paper. The resuh could be summarized as follows： the average contents of Cu, Pb, Cd and Zn in sea water were 1.75 μg. L^-1, 1.69 μg. L^-1, 0. 02 μg. L^-1, 2. 84 μg.L^-1 respectively and when compared with different seasons, the tendency of heavy metals contents in sea water was： October 〉August 〉 May. The average contents of Cu, Pb, Cd and Zn in sediments were 14. 0 rag. kg^-1, 34. 8 mg. kg^-1, 0. 031 mg. kg^-1, 97.5 mg. kg^-1 , respectively. The results of environmental quality showed that the contents of four heavy metals in seawater were below the second degree of Sea Water Quality Standard and belonged to the grade of ＂green＂. On the other hand, the contents in sediments were all less than the values of the first degree of Standard for Marine Sediments Quality and belonged to the grade of ＂less green＂. And it showed that the potential ecological risk factors of Pb, Cd were larger than the factors of Cu, Zn from the assessed result of ecological risk. Whereas, the potential ecological risk of heavy metals in sediments of the whole culture areas was still light and the environmental quality of culture areas was well.