渤海湾潮间带表层沉积物重金属潜在风险评价

Assessment of Potential Risk of Heavy Metals in the Surface Sediments in the Intertidal Zone of the Bohai Bay

分析了渤海湾潮间带表层沉积物重金属(Cu,Pb,Zn,Cd和Cr)含量及分布特征,并采用潜在生态危害指数法对渤海湾潮间带表层沉积物进行评价。结果表明,此5种元素含量均未超出海洋沉积物质量标准一类标准。Cu、Pb、Cd、Cr分布特征基本相似,高值出现在站位4和站位11,Zn的分布特征不同,质量分数变化很大,存在明显的高值和低值,区域相差很大。从单个元素污染系数来看,Pb、Cr、Cu、Zn属于低污染程度,Cd属于中等污染程度,总体污染污染指数小于8,属于低污染程度。5种元素的潜在生态风险由高至低为Cd、Pb、Cr、Cu和Zn,其中,Pb、Cr、Cu和Zn的单个元素的危害系数属于低微生态风险等级,Cd属于中等生态风险等级。

The contents and distributions of heavy metals(Cu,Pb,Zn,Cd and Cr)in the surface sediments in the intertidal zone of the Bohai Bay are analyzed,and the sediments are evaluated by using the potential ecological hazard index method.The results show that all these 5 elements do not exceed the quality standard(Class I)of marine sediments.The distribution characteristics of Cu,Pb,Cd,Cr are basically similar,with the high values being at Station 4 and Station 11.But Zn has a different distribution and its content changes greatly and shows obviously high and low values in different zones.From the pollution coefficient of an individual element,it can be seen that Pb,Cr,Cu,Zn belong to a low pollution degree and Cd to a medium pollution degree.The total pollution index is less than 8,belonging to a low pollution degree.The order of the potential ecological risk of the five elements is Cd,Pb,Cr,Cu,Zn,of which the hazard coefficient of an individual element Pb,Cr,Cu,Zn belongs to the lower ecological risk class and that of Cd belongs to the middle ecological risk class.