长江口洋山海域表层沉积物重金属的富积及其潜在生态风险评价

根据长江口洋山海域表层沉积物监测资料,利用变异系数法和富积系数法,对表层沉积物中重金属的空间波动程度及富积程度进行了分析,并采用Hakanson潜在生态危害指数法对其潜在生态危害程度进行了评价.结果表明:在表层沉积物所监测的重金属中,Pb元素的空间波动程度最高,其它重金属元素的空间波动程度较低,各重金属空间波动程度的顺序依次为Pb＞Cd＞Hg＞Cu＞Cr＞As＞Zn;沉积物中Cu元素的富积程度最高,Pb元素次之,其它重金属元素的富积程度较低,各重金属富积程度的顺序依次为Cu＞Pb＞Zn＞As＞Cr＞Cd＞Hg.潜在生态危害评价结果显示:洋山海域表层沉积物中的重金属对海洋生态系统的潜在生态危害较轻微,均属于轻微潜在生态危害程度,其轻微潜在生态危害程度顺序为Cu＞As＞Hg＞Pb＞Cd＞Cr＞Zn.

ACCUMULATION OF HEAVY METALS IN SURFACE SEDIMENTS FROM THE SEA REGION OF YANGSHAN IN THE YANGTZE ESTUARY WITH ASSESSMENT OF THEIR POTENTIAL ECOLOGICAL RISK

Based on the monitoring data of surface sediments from the Sea Region of Yangshan in the Yangtze Estuary,the degree in spatial fluctuation and accumulation of heavy metals was analyzed by using the method of variation coefficients and accumulation coefficients.The method of potential ecological risk indices presented by Lar Hakanson was used to assess the potential ecological risk of heavy metals.The degree of Hg spatial fluctuation appears to be the highest and other heavy metals being rather lower in surface sediments,with the order of fluctuation degree ranging as the following: Pb > Cd > Hg > Cu > Cr > As > Zn.The degree of Cu accumulation appears to be the highest among all heavy metals analyzed in surface sediments,with Pb being the second,and others lower.The order of the accumulation degree of these heavy metals is as: Cu > Pb > Zn > As > Cr > Cd > Hg.The assessment of potential ecological risk revealed that the potential ecological risk of these heavy metals to the ocean ecology system is very light,which belongs to light potential ecological risk level,with the order of light potential ecological risk level of all these heavy metals ranging as: Cu>As>Hg>Pb>Cd>Cr>Zn.