重庆长寿湖周边地区土壤重金属污染评价

对重庆长寿湖周边地区土壤中重金属元素的含量进行了调查,分析了重金属的空间结构特征,探讨了其主要来源,采用Hakanson潜在生态风险指数法评价了各种重金属的潜在生态风险。结果表明,①土壤中重金属Hg、Cd和As的富集较为严重,超过了土壤质量一级标准。②Ni和Cu的含量主要受土壤形成因子,如地形、土壤类型等的控制;Pb、Cd、Zn很大程度来源于人类活动产生的污染;其他重金属元素的含量受内在和外在因子的共同影响。③长寿湖周边地区重金属污染是轻度和中等生态危害,中等生态危害面积4 821.66 hm2,占总面积的43.23%,主要生态风险因子是Hg和Cd,分别达到了较强生态危害和中等生态危害。

Evaluation of Soil Heavy Metal Pollution in Changshou Lake Surrounding Area of Chongqing

The content of heavy metals in surrounding area of Changshou Lake was investigated;the spatial structure feature and main sources of heavy metals were explored;and the potential ecological risk of heavy metals was evaluated by Hakanason ecological risk index.Results were as follows.①Hg,Cd and As were highly enriched in this area as their concentration exceeded the first grade of soil quality.②The content of Ni and Cu was affected by soil formation factors such as terrain and soil type;the source of Pb,Cd and Zn was mainly human activities around this area;the content of other metals was influenced by both inner and external factors.③Heavy metal contamination in surrounding area of Changshou Lake belonged to slight and medium ecological risk.The area of which suffering medium ecological risk was 4 821.66 hm2,accounting to 43.23% of the total area.The main ecological risk factors were Hg and Cd,which had strong ecological risk and medium ecological risk,respectively.