基于相平衡分配法的店埠河沉积物重金属质量基准研究

Application of equilibrium partitioning approach to derive sediment qualityguideline (SQG) values for heavy metals in the Dianbu River

以店埠河为研究对象,采用校正后的相平衡分配法推导了店埠河沉积物中5种重金属(Cr、Cu、Zn、Cd、Pb)的沉积物质量基准(SQG)值,并分析了各金属结合相对不同重金属沉积物质量基准的贡献。结果表明:店埠河沉积物中Cr、Cu、Zn、Cd和Pb的沉积物质量基准值分别为318.80、122.24、1326.99、7.88和31.43 mg/kg;各金属结合相对不同重金属的沉积物质量基准值的贡献存在差异,细颗粒物(粒径<63μm)对店埠河5种重金属沉积物质量基准值的贡献率为24.49%~48.93%,其中对Cr、Zn和Cu的沉积物质量基准值的贡献最大。酸可挥发性硫化物对Cu、Zn、Cd和Pb的沉积物质量基准值的贡献率分别为2.11%、0.22%、50.13%和21.67%,主要决定着Cd的SQG。总有机碳和残渣态对这5种重金属SQG的贡献率较低,均不足3%。

The Dianbu River was taken as the study object,the normalized equilibrium partitioning approach was used to derive the sediment quality guideline(SQG)values of five heavy metals(Cr,Cu,Zn,Cd,Pb)in the sediments of the river,and the contribution of each metal binding phase to the SQG value for five different heavy metals was analyzed.The results showed that the SQG values of Cr,Cu,Zn,Cd,and Pb in the sediments of the Dianbu River were 318.80,122.24,1326.99,7.88 and 31.43 mg/kg,respectively.There were differences in the contribution of each metal binding phase to the SQG values of five heavy metals.The contribution rate of fine particulate material(particle size<63μm)to the SQG values of five heavy metals in the sediments of the Dianbu River was 24.49%-48.93%,and the contribution rate to the SQG values of Cr,Zn and Cu sediments were the largest.The contribution rate of acid volatile sulfide to the SQG values of Cu,Zn,Cd and Pb was 2.11%,0.22%,50.13%and 21.67%,respectively,which mainly determined the SQG value of Cd.Total organic carbon and residual state contributed less than 3%to the SQG values of these five heavy metals.