连云港近岸海域表层沉积物中重金属的分布特征及潜在生态危害

Distribution of Heavy Metals and Potential Ecological Risk in Surface Sediment of Offshore Marine Areas in Lianyungang

采用变异系数、富集系数、潜在生态危害指数分析评价连云港近岸海域表层沉积物中的重金属的相关特性。结果表明:重金属的空间分布离散性及富集程度存在明显差异,重金属元素空间波动程度依次为Cu=Cd>Hg>Cr>As>Zn>Pb,富集程度依次为Zn>Cr>Cd>Cu>As>Pb>Hg;除Cd在5号站位处于中等污染水平外,其他各重金属的潜在生态危害处于轻微水平,潜在生态危害系数依次为Cd>Hg>As>Cu>Pb>Cr>Zn,港口区域重金属富集程度较重,潜在生态危害指数相对较高;有机碳和酸可挥发性硫化物影响到重金属的迁移与转化,进而影响其潜在生态危害程度及生物毒性。

This paper analyzed the correlation of heavy metals in sediment of Lianyungang sea area by the methods of variation coefficients, concentration coefficients and potential ecological risk indexes. The results showed that significant differences existed in spatial distribution and accumulation of heavy metals, the extent of spatial fluctuation was in order of Cu = Cd 〉 Hg 〉 Cr 〉 As 〉 Zn 〉 Pb, the extent of the accumulation was in order of Zn〉Cr〉Cd〉Cu〉As〉Pb〉l-lg; The potential ecological risk of heavy metals to ocean ecology system was very slight except for Cd which was at middle pollution level found at 5 stations, the potential ecological risk was in order of Cd〉Hg〉As〉Cu〉Pb〉Cr〉Zn, the accumulation of heavy metals was serious and the potential ecological risk was high in port area; Organic carbon （DOC） and acid volatile sulfide （AVS） influenced the transport and transform process of heavy metals and then influenced the potential ecological risk level and biotoxicity.