粤北地区森林土壤重金属含量特征及生态风险评价——以曲江区为例

Heavy Metal Content Characteristics and Ecological Risk Assessment of Forest Soil in Northern Guangdong Province: A Case Study of Qujiang District

以曲江区森林土壤为研究对象,分析0~20 cm土层土壤中Cr、Ni、Cu、Zn、As、Cd、Pb和Hg的含量,并采用单因子指数法、内梅罗综合指数法和潜在生态风险指数法对土壤重金属含量进行污染评价和生态风险评价。结果表明,8种重金属元素的单因子指数均小于1,污染等级为无污染;内梅罗综合指数小于0.7,综合污染等级为安全状态;单一重金属潜在生态风险指数表现为Cr、Ni、Cu、Zn、As、Pb元素为轻度风险,Cd元素为中度风险,Hg元素为强度风险;综合潜在生态风险等级为中等生态风险。总的来说,研究区存在一定程度的潜在生态风险,应加强重金属污染源的控制,减少重金属进入土壤,降低重金属污染风险。

To understand the characteristics of heavy metal content and pollution of forest soil in Qujiang district, and provide a theoretical basis for its ecological risk assessment. In this study, the contents of Cr, Ni, Cu,Zn, As, Cd, Pb and Hg in the 0-20 cm soil layer of forest soil in Qujiang district were analyzed, and the pollution and ecological risk assessment of heavy metal content in soil were carried out by single factor index method,Nemero comprehensive index method and potential ecological risk index method. The results showed that the single factor index of 8 heavy metals was all less than 1, and the pollution grade was no pollution. Nemero composite index is less than 0.7, and the comprehensive pollution level is safe. The potential ecological risk index of single heavy metals showed that Cr, Ni, Cu, Zn, As and Pb were mild risk, Cd was moderate risk, and Hg was intense risk. The comprehensive potential ecological risk level is medium ecological risk. In general, there is a certain degree of potential ecological risk in the study area, so it is necessary to strengthen the control of heavy metal pollution sources, reduce the entry of heavy metals into the soil and reduce the risk of heavy metal pollution.