中文摘要：

实地采集了15个土壤剖面样品,并对其中的Pb、Cd、Hg、As、Cu、Cr、Zn和Ni含量进行分析监测,采用潜在生态危害风险评价法对研究区域土壤中重金属的污染状况进行了评价,并通过工程措施进行了污染土壤修复治理。结果表明,在0～20 cm土层范围内,Zn质量比在89.80～724.03 mg/kg之间,Cu质量比在28.89～1 271.81 mg/kg之间,Hg质量比介于0.04～4.48 mg/kg之间,Pb质量比介于48.69～12 021.15 mg/kg之间。Cd质量比在0～120 cm范围内均超过了土壤环境质量二级标准,而且Pb、Cd、Hg、Cu和Zn在0～120 cm范围内全部超过了关中塿土背景值。潜在生态危害风险评价表明,Cd的潜在生态危害系数范围为26.0～21 118.6,轻微、中等、较强、很强和极强的生态危害频率分别为4.3%、15.2%、19.6%、15.2%和37%;Pb的潜在生态危害系数范围为0.1～120.2,轻微、中等和较强的生态危害频率分别为93.5%、4.3%和2.2%;Hg的潜在生态危害系数范围为0.1～83.4,轻微、中等和较强的生态危害频率分别为59.3%、39.4%和1.3%;As、Ni、Zn和Cu均具有轻微生态危害。研究区域土壤重金属污染主要是Cd、Hg和Pb等形成的复合污染。采用原位挖掘-异位固化-客土回填法,对研究区域进行污染土壤工程修复,可获得良好的修复效果。

英文摘要：

To remediate the heavy metals polluted soil around a closed smelter in Shaanxi Province,15 soil profile samples were collected in the site and analyzed for heavy metals content,including Pb,Cd,Hg,As,Cu,Cr,Zn and Ni. The pollution situation was assessed by using the ecological hazard risk assessment method,and the contaminated soil was finally remediated by in-situ replacement engineering methods. The results showed that within top 0 ～ 20 cm soil layer,Zn contents ranged from 89. 80 mg / kg to 724. 03 mg / kg,Cu contents varied from 28. 89 mg / kg to 1 271. 81 mg / kg,Hg contents changed from0. 04 mg / kg to 4. 48 mg / kg,and the Pb contents were around 48. 69 ～ 12 021. 15 mg / kg. Cd contents in the top soil layer of 0 ～ 120 cm were above the secondary standard value of soil environment quality,while Pb,Cd,Hg,Cu and Zn contents in soil within 0 ～ 120 cm were higher than those of the Lou soil background values. The results of potential ecological risk implicated that the potential ecological risk factor for Cd ranged from 26. 0 to 21 118. 6,and its slight,moderate,strong,very strong and extremely strong ecological hazards frequencies were 4. 3%,15. 2%,19. 6%,15. 2% and 37%,respectively.The potential ecological risk factor of Pb ranged from 0. 1 to 120. 2,and its slight,moderate and strong ecological hazards frequencies were 93. 5%,4. 3% and 2. 2%,respectively. The potential ecologicalrisk factor of Hg ranged from 0. 1 to 83. 4,and its slight,moderate and strong ecological hazards frequencies were 59. 3%,39. 4% and 1. 3%,respectively. Elements As,Ni,Zn and Cu,all had slight ecological hazards. The soil heavy metals pollution in the study area was mainly contributed by Cd,Pb and Hg. The in-situ replacement method was proved to be an efficient method for the smelter polluted soil remediation and it could achieve satisfactory performance.