鸭绿江口及毗邻浅海沉积物重金属富集特征与潜在生态风险比较

为研究鸭绿江河口及毗邻浅海沉积物中重金属的污染状况,比较了鸭绿江口及毗邻浅海表层沉积物重金属的富集系数、多金属污染度的沿程变化,分析了重金属的分布富集规律;讨论了采用不同的背景值在潜在生态风险指数、地累积指数、生物效应浓度3种评价方法中的差异及其对生态风险评价结果的影响.结果表明:鸭绿江口及毗邻浅海的潜在生态风险总体属于低风险等级,其中毗邻浅海和潮滩的重金属污染较轻,西汊道的污染相对较重.重金属的高值分布区与混浊带具有一定的对应关系,但受人类活动的影响更大,对鸭绿江口及毗邻浅海表层沉积物重金属污染生态风险评价贡献率较高的重金属污染因子是Cu,Hg和Cd.

Comparative Study of Enrichment Features and Potential Ecological Risks of Heavy Metals in Sediments of the Yalu River Estuary and Its Adjacent Shallow Sea Area

The longitudinal variation of the enrichment coefficients of heavy metals and the multi-metallic pollution degree in surface sediments were compared in the Yalu River estuary and its adjacent shallow sea area.At the same time,the distribution and enrichment patterns were also analyzed,in order to study the heavy metal pollution in the area.The differences among three assessment methods with different background values on potential ecological risk index,geoaccumulation index and bio-effect concentration were discussed,in addition to the influence of the three methods on ecological risk evaluation.The research results demonstrated that the total potential ecological risk was at a low level in the Yalu River estuary and its adjacent shallow sea areas.The heavy metal pollution was comparatively light in the adjacent shallow sea areas and tidal bank,in contrast with the western riverway of the Yalu River.There was a certain corresponding relationship between the higher value distribution zone of heavy metals and the turbidity belt.However,the distribution of heavy metals was obviously influenced by human activities.Cu,Cd and Hg had higher contribution rates to the ecological risk evaluation of heavy metal pollution in the surface sediments of the Yalu River estuary and its adjacent shallow sea areas.