宿鸭湖水库沉积物重金属含量分析与评价

Analysis and Evaluation of Heavy Metals in Sediments of Suyahu Reservoir

为了解宿鸭湖水库库底沉积物中重金属污染水平,对沉积物中As、Cd、Cr、Cu、Ni、Pb、Zn、Hg等8种重金属含量进行了研究,并采用地积累指数法、污染负荷指数法、沉积物质量基准法及潜在生态风险指数法进行了综合评价,结果表明:重金属在沉积物上部含量较高,且Cd、Hg在空间分布上差异较大;根据相关性分析,Ni、Cr、As、Pb、Zn之间以及Cd、Hg之间关系密切;Cd的地积累指数值较高,属于无污染到中污染;根据污染负荷指数法污染分级标准,所有采样点中有4个采样点为无污染,16个采样点为中等污染;根据沉积物质量基准法,Ni和As可能对水体产生不利影响;根据潜在生态风险指数法,宿鸭湖水库库底沉积物重金属整体处于轻微风险至中等风险,且主要受Hg和Cd的影响。

In order to understand and evaluate the pollution level of heavy metals in sediments at the bottom of Suyahu Reservoir, the contents of As, Cd, Cr, Cu, Ni, Pb, Zn and Hg in sediments were studied. And the methods of land accumulation index, pollution load index, sediment quality benchmark and potential ecological risk index were used for comprehensive evaluation. The results show that the content of heavy metals in the upper part of sediment is higher and the spatial difference of Cd and Hg is larger. According to the correlation analysis, there is a significant positive correlation between Ni, Cr, As, Pb and Zn and Cd and Hg. The geoaccumulation index value of Cd is higher. According to the classification of PLI, there are 4 none pollution in all sampling points of reservoir and the other 16 samples are of medium pollution. According to sediment quality standard method, Ni and As may have slight adverse effects. In potential ecological risk analysis, the overall risk is between slight risk and medium risk and is mainly affected by Hg and Cd.