长江口及毗邻海域沉积物生态环境质量评价

Sediments eco-environmental quality assessment in the Changjiang Estuary and its adjacent waters

采用地质累积指数法、潜在生态危害指数法和生物效应浓度法3种方法,考虑河口的水动力过程、沉积物分布和盐度影响,把长江口及毗邻海域划分为7个区域进行沉积物生态环境质量评价。结果表明,3种方法评价结果基本一致,长江口及毗邻海域的底质生态环境均受到重金属不同程度的污染,属于中低度污染,口外区和舟山海区的沉积物质量较好,口门、最大浑浊带和杭州湾的沉积物质量较差。用同期的底栖动物群落结构参数进行验证,生态响应明显。

Methods of indexes of geo-accumulation, potential ecological risk index, and biological effects of concentration are applied to evaluate the eco-environmental quality of sediments in the Changj iang estuary and its adjacent waters which are divided into 7 zones by Cluster analysis in consideration of hydrodynamic process and deposition process and salinity impact. The results showed that three methods of evaluation findings are basically the same, The environment of the foundation of the study area is subject to varying degrees of heavy metal pollution, while the quality of sediments outside of the estuary and sea area nearby Zhousan is good and poor at the estuary and turbidity maximum Zone and Hangzhou bay. The degree of Hg spatial fluctuation appears to be the highest in surface sediments, with the order of heavy metals fluctuation degree ranging as the following：Hg 〉 Cd 〉 Cu 〉 Pb 〉 As 〉 Zn. Ecological responses are obviously discovered in the validation based on the corresponding period macrobenthic community parameters.