【摘要】 为了解保定城市土壤重金属污染状况及潜在生态危害,以保定城市土壤为研究对象,采用单因子指数法、尼梅罗综合指数法、潜在生态危害指数法对保定城市土壤重金属污染特征及潜在生态危害进行评价。结果表明,保定城市土壤As、Cd、Hg、Pb、Cr、Cu、Zn、Ni的平均值分别为9. 75 mg/kg、0. 18 mg/kg、0. 21 mg/kg、38. 99 mg/kg、66. 30 mg/kg、29. 10mg/kg、122. 36 mg/kg、28. 05 mg/kg。保定城市土壤中重金属元素平均值(除As、Ni、Cr外)均高于河北省土壤背景值,其中Hg、Pb、Zn元素的平均值较大,分别是河北省土壤背景值的5. 28倍、1. 74倍、1. 75倍,表明这些元素受到人为因素及工业活动的影响。保定城市土壤重金属污染程度从大到小依次为Zn、Pb、Hg、Cd、Cu、Cr、Ni、As,其中Cd、Pb、Cu以清洁状态为主,Hg以安全状态为主,As、Cr、Ni元素处于完全清洁状态,Zn元素出现污染,面积达到研究区面积的2. 08%。整体而言,保定城市土壤环境良好,局部污染,清洁、安全、警戒土壤面积比例分别为64. 58%、33. 33%、2. 08%,主要出现在保定市北部地区,其形成可能与工业生产及人类活动有关。保定城市土壤重金属潜在危害程度由大到小依次为Hg、Cd、As、Pb、Cu、Zn、Cr、Ni。各重金属元素中,产生潜在生态危害的重金属主要是Hg,已达到很强潜在生态危害水平,其余重金属均为轻度潜在生态危害;综合潜在生态危害指数(RI)达到中等生态危害程度,达到强生态危害和很强生态危害程度的面积之和占研究区总面积的35. 41%,其形成可能与工业生产有关。更多还原

【Abstract】 To assess the status and potential ecological risk of heavy metals in the urban soil of Baoding City,Hebei,the paper has done an analysis of the pollution contamination features and the potential risks of the heavy metal residue with the methods of the single factor index,the Nemerow comprehensive index and the potential risk index. The results of the above investigation and examination show that the average content concentration of the elements As,Cd,Hg,Pb,Cr,Cu,Zn and Ni in soils come out to be 9. 75 mg/kg,0. 18 mg/kg,0. 21 mg/kg,38. 99 mg/kg,66. 30 mg/kg,29. 10 mg/kg,122. 36 mg/kg and 28. 05 mg/kg respectively. And the average content concentration ratesof heavy metals in the soil( except for As,Ni and Cr) prove to be higher than the background average rates of the whole province,especially in accordance with those of Hg,Pb and Zn,which are 5. 28 times,1. 74 times and 1. 75 times higher,respectively,than those of the background rates. The above average statistical investigation results also suggest that the areas concerned have been contaminated by anthropogenic and industrial activity leftovers. The pollution degree extent of the heavy metals in the areas of Baoding is in a descending order of Zn,Pb,Hg,Cd,Cu,Cr,Ni,As. Moreover,it is also necessary to point it out that the said area under study are generally free from the pollution of Cd,Pb and Cu. More detailed study shows that,Hg is at present limited in a safe condition,whereas As,Cr and Ni are in a totally clean,or,free-from pollution condition,though Zn remains in a really serious pollution status,which accounts for about 2. 08% of the study area. Thus,on the general,the status of the urban soil in Baoding remains in a safe condition,except for some few slightly polluted areas located mainly in the north of the city probably due to the humanistic and industrial activities.Thus,statistically speaking,the clean,safe and alert soil surface activities may account for about 64. 58%,33. 33% and2. 08%,respectively,whereas the potential risks of heavy metal pollution influential degrees can be illustrated in the following descending order of Hg,Cd,As,Pb,Cu,Zn,Cr,Ni. Finally,it is also necessary to point it out that,the pollution of Hg has,indeed,reached higher potential risk level,though the rest heavy metals remain at lower ones. Thus,in general,the comprehensive risk index can be said to have gone up to an intermediate potential risk level,and the surface soil of the city has seriously been and/or strongly been polluted due to the industrial production,and has gone up to 35. 41% of the area under study.更多还原