随着城市化的快速发展,作为城市环境主要受体的城市土壤已经收到严重的污染,尤其是重金属的污染.以地质累积指数法和潜在生态危害指数法为评价方法,对石家庄城市表层土壤中的8种重金属元素进行了污染评价和潜在生态危害评价;评价认为:石家庄城市表层土壤中重金属元素平均值(除As、Ni外)均高于河北中南部平原的区域背景值;其中Hg、Cd、Zn元素的平均值较大.表层土壤中重金属元素Hg、Cd、Zn元素的富集系数较大,表明这些元素受到人为因素及工业活动的影响.整体而言,石家庄城市表层土壤环境整体良好,局部污染;警戒、污染土壤面积比例之和达到3. 18％.潜在生态危害评价认为:石家庄城市表层土壤重金属元素Hg、Cd的潜在生态危害较大;其中Hg达到了强生态危害,Cd达到了中等生态危害.综合评价8种重金属元素的潜在生态危害性,石家庄城市表层土壤整体表现为中等潜在生态危害.在研究评价基础上提出防治对策.%With the rapid development of urbanization, the topsoil, as main receiver of the city environment, has been polluted, especially by the heavy metals. Based on geo-accumulation index analysis and potential ecological risk index analysis, the soil pollution and potential ecological risk of main eight heavy metals in topsoil of Shijiazhuang were analyzed and assessed. The results indicate that the average value of heavy metals (except As and Ni) in topsoil of Shijiazhuang is higher than background values of central and southern plain of Hebei Province, Hg, Cd and Zn the highest. The enrichment coefficient of heavy metals (except As and Ni) is above 1, Hg, Cd and Zn in the highest level, this results reveal the pollution is caused by the joint action of man-made factors and industrial activities. Generally speaking, the topsoil of Shijiazhuang is keeping in good condition, and the surface of soil partially polluted, on the alert and completely polluted reached to 3, 18％. According to potential ecological risk index analyze, it can be concluded that Hg and Cd has the greatest potential risk, Hg in the highest level and Cd in medium level. Considering all eight elements, generally concluding, the soil environment of Shijiazhuang has been in the medium ecological risk level. Based on the above analysis, the prevention countermeasures are proposed.
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