东湖沉积物重金属来源与人类活动相关性分析

城市化和工业化进程给城市湖泊带来了很高的重金属污染负荷。为研究湖泊重金属污染的来源以及人类活动对湖泊重金属污染的影响,以武汉郭郑湖为例,测定了沉积物中几种常见痕量重金属元素Co、Cr、Pb、Cu、Zn、Ni的含量,并采用地累积指数法和归一化法对重金属污染物的污染程度和污染来源进行了分析。研究结果表明,溢流排污口处沉积物重金属污染程度较高,Zn、Cu和Pb的污染程度高于Co、Cr、Ni,为湖泊主要污染物。归一化法分析表明:Zn、Pb、Cu之间呈显著相关,均以人类活动输入为主要来源。在溢流排污口处Ni和Cr受人类活动影响较轻微,Co以自然来源为主;在湖心处Ni、Cr、Co均以自然来源为主。以上结果表明,对郭郑湖的治理应以Zn、Pb、Cu为主。

Sources of Heavy Metal Pollutions in Sediments of Lake Donghu and Their Relationship with Anthropogenic Activities

The urbanization and industrialization process had caused high loads of heavy metals to the urban lakes. In order to study the sources of heavy metal pollutions and the impact of anthropogenic activities in an urban lake-Guozhen Lake in Wuhan, the contents of 6 trace heavy metals such as Co, Cr, Pb, Cu, Zn, Ni were determined. By using the index of geoaccumulation and normalization method, two sediment cores from the Lake were analyzed and their pollution degree and source were studied. Results show that high pollution extent of heavy metal was found at the sewage draining exit of the overflow. Zn, Pb, Cu are the dominating contaminative elements in the Lake which pollution degree are higher than Co, Cr, Ni. Normalization method analysis of heavy metal contents shows that Zn, Pb, Cu are positively correlated with each other, and seriously contaminated by human pollution. At the sewage draining exit of the overflow, Ni and Cr are partly contaminated by humans, while Co is from natural source. In the center of the Lake, all of Ni, Cr and Co are from natural source. The data shows that controlling the heavy metal pollutions of the Lake should give first place to Zn, Pb and Cu.