鸭绿江口湿地沉积物-上覆水重金属环境质量状况及其生态风险评价

The assessment on environmental quality conditions and potential ecological risk of heavy metals in the sedimentsoverlying water of the Yalu River Estuary wetland

基于代表鸭绿江口湿地不同区域的34个研究点位的调查数据,利用内梅罗指数法对其沉积物-上覆水重金属环境质量状况进行评价,再利用Hakanson潜在生态风险指数法对表层沉积物的生态风险进行评价。结果表明,鸭绿江口湿地表层沉积物质量处于较清洁水平,而上覆水水体质量属于轻污染水平,总体表现为自鸭绿江河口到大洋河口污染强度逐渐降低的趋势。鸭绿江口湿地表层沉积物重金属潜在生态危害系数和潜在生态风险指数均较低,属于低污染水平,Cd和Cu是潜在生态危害较大的因子。鸭绿江主河道和西水道部分区域表层沉积物污染较为明显,Cu、Pb是鸭绿江口湿地的主要污染因子。

The data from 34 sampling points represented different zones of Yalu River Estuary wetland were studied to assess the conditions of heavy metals and its potential ecological risks in the sediments-overlying water by using Nemerow index and Hakanson potential ecological risk index,respectively.The results showed that the quality of heavy metals condition in the surface of sediment presented at a cleaner level,while that at light polluted level in the overlying water.The pollution degrees from the Yalu River Estuary to Dayang River Estuary reduced gradually.The ecological harm coefficient and potential ecological risk index of the heavy metals were low in the surface of sediment and indicated slight ecological risk.The heavy metals including Cd and Cu were the major factors of potential ecological risk.The pollution in the surface of sediment in some areas from the main and west channel of Yalu River was more obvious than other parts.The elements such as Cu and Pb were the main pollution factors of Yalu River Estuary wetland.