生态环境学报2018，Vol.27Issue(4)：776-784,9.DOI:10.16258/j.cnki.1674-5906.2018.04.025
贵州草海菜地表层土壤重金属污染特征及生态风险评价
Characteristics of Heavy Metals Pollution and Ecological Risk Assessment of the Surface Soils in the Vegetable Fields around Caohai in Guizhou
摘要
Abstract
Caohai is a typical highland wetland ecosystem in Guizhou province. It is of great significance to evaluate the characteristics of heavy metals pollution and ecological risk of surface soils in the vegetable fields around Caohai, which will be helpful for protecting the land resource and the vegetable food safety and for soil pollution control of the production area. 8 representative vegetable field surface soils were collected around Caohai to determinate the concentrations of Zn, Cu, Cr, Pb, Ni and As, and their distribution characteristics and sources were analyzed and ecological risk were assessed. The results showed that the concentrations of heavy metals in the vegetable field surface soils around Caohai were Zn (159.06 mg·kg-1)>Cr (92.11 mg·kg-1)>Pb (63.72mg·kg-1)>Ni (45.74 mg·kg-1)>Cu (27.75 mg·kg-1)>As (24.58 mg·kg-1). Among them, the concentrations of Zn, As, Pb and Ni were higher than the background values of soil heavy metals in Guizhou province, and the concentrations of Cu and Cr were lower than the background values. However, the concentrations of 6 kinds of the heavy metals were all lower than the values of the ClassⅡ Standard of the Soil Environment Quality Standards (GB15618—1995). The variation degree of Zn, Cr and Ni belonged to medium, their concentrations obeyed the normal distribution. And the variation degree of Cu belonged to medium, As and Pb belonged to height, and their concentrations obeyed the skewed positive distribution. The correlation between Zn and Cu was very significant (P<0.01), and Cu and Pb, Ni and As, Cr with Pb and Ni wassignificant (P<0.05), respectively. The soil environmental quality assessment indicated that Cu, Cr, Ni and As belonged to light pollution, Zn and Pb were medium pollution. As for the ecological risk assessment, the risk index (RI) value of 6 kinds of heavy metals was 23.92, which was lower than the lowest value of RI (RI=150), and indicated the degree belonged to slight . The source analysis showed that factor 1 (F1) contained Zn and As, factor 2 (F2) contained Cr and Pb, and factor 3 (F3) contained Cu. And F1 and F2 were the exogenous factors, which were on behalf of the agriculture, industry, mining and household garbage. F3 was the natural factor, which was on behalf of the formation of soil parent material. Therefore, the sources of Zn, As, Cr, Pb and Ni in the vegetable field soils around Caohai might be related to the agriculture, industry, mining and household garbage, and the source of Cu might be related to the soil parent material.关键词
重金属/草海/菜地土壤/生态风险评价/土壤环境质量Key words
heavy metals/Caohai/vegetable field soil/ecological risk assessment/soil environmental quality分类
资源环境引用本文复制引用
赵斌,朱四喜,杨秀琴,吴云杰,汤茜,顾金峰..贵州草海菜地表层土壤重金属污染特征及生态风险评价[J].生态环境学报,2018,27(4):776-784,9.基金项目
国家自然科学基金项目(31560107) （31560107）
贵州省研究生科研基金项目(KYJJ2017006) （KYJJ2017006）
