鄱阳湖湖口段沉积物重金属污染特征及潜在生态风险评价

Pollutant Characteristics and Ecological Risk Assessment of Heavy Metals in Sediments from the Confluent Area of Yangtze River and Poyang Lake

为了解鄱阳湖与长江交汇区沉积物中重金属含量以及各污染物的潜在生态危害程度,通过采样分析As、Cd、Cr、Cu、Hg、Pb、Zn等7种重金属含量及污染特征分布的基础上,采用地积累指数法和潜在生态风险指数法对鄱阳湖底泥中的重金属污染进行综合性的评价分析.结果表明,鄱阳湖湖口段沉积物已经受到了不同程度的重金属污染;沉积物中Cd、Cu和Hg受人为影响比较严重,Cr、Cu、Hg、Pb和Zn均存在一定程度的积累;区域重金属元素潜在生态风险主要受制于Hg和Cu,潜在生态风险贡献率大小排序为:Hg(38.4%)>Cu(27.8%)>Pb(10.9%)>Cd(9.1%)>As(8.0%)>Cr(4.0%)>Zn(1.8%).

In order to investigate the heavy metals content and the pollutant potential ecological hazards in sediments from the confluent area of Yangtze River and Poyang Lake,the contamination of sediment heavy metals in Poyang Lake was comprehensively assessed by the geoaccumulation index and the potential ecological risk index based on sampling analysis of heavy metals（As,Cd,Cr,Cu,Hg,Pb and Zn） and pollutant characteristics.The results showed that the sediments in Poyang Lake were polluted to a certain degree by heavy metals,from which Cd,Cu and Hg were mainly influenced by human activities,and Cr,Cu,Hg,Pb,and Zn were accumulated in the study area.The potential ecological risk of heavy metal elements in the region were mainly controlled by Hg and Cu,and their contribution rates were sorted by size as follows：Hg（38.4%） Cu（27.8%） Pb（10.9%） Cd（9.1%） As（8.0%） Cr（4.0%） Zn（1.8%）.