摘要
以山西省寿阳县7个典型常规农业村耕地为研究对象,采集耕作层126个土壤样品,测定其Cd、Hg、As、Cu、Pb、Ni、Cr、Zn 8种重金属的含量。运用单因子污染指数法(P)、污染负荷指数法(PLI)和潜在生态风险评价法(RI)评价土壤重金属污染和潜在生态风险程度,应用空间插值法探讨土壤重金属污染和潜在生态风险空间分布,并对重金属污染的来源进行讨论。结果表明:该区域土壤除As的平均含量低于山西省土壤元素背景值外,其余重金属元素平均含量均高于山西省土壤元素背景值,Cu、Ni、Pb、Zn、Cd、Cr和Hg的平均含量分别为山西省元素背景值的1.03、1.03、1.13、1.15、1.55、1.72和2.26倍。从单因子污染指数看,Hg属于中度污染,Cd、Cr、Zn、Cu、Ni、Pb为轻微污染,As则没有发生污染。从综合污染指数看,该区域土壤8种重金属所有样点的PLI平均为1.09,总体上属于轻度污染。从综合潜在生态风险指数看,所有样点8种重金属的RI平均为151.47,属于中度生态风险水平,其中Hg和Cd为主要贡献因子,其他重金属的生态风险很低。该区域PLI和RI的空间分析显示,8种重金属污染和潜在生态风险均呈现一定的空间差异,但二者的空间分布格局基本一致。在局地自然地理条件基本一致的情况下,雾霾、燃煤、煤矿生产以及农业生产是造成该区土壤重金属含量增加的重要原因,而农户行为则可能是造成部分地块土壤重金属污染和生态风险突出的原因之一。
One hundred and twenty-six farmland topsoil(0~20 cm)samples were collected from the seven conventional agricultural villages,Shouyang county,Shanxi province,China,and then the concentrations of Cd,Hg,As,Cu,Pb,Ni,Cr and Zn in the samples were measured by standard methods.Soil pollution levels and potential ecological risks of heavy metals were assessed using single factor pollution index(P),pollution load index(PLI)and potential ecological risk index(RI),respectively.Ordinary Kriging interpolation technique was employed to investigate the spatial distribution of PLI and RI of in the seven conventional agricultural villages.The results showed that content of As in farmland soils in the seven conventional villages was less than the soil background of Shanxi province,the average concentrations of Cu,Ni,Pb,Zn,Cd,Cr and Hg in farmland soils in the seven conventional villages were 1.03,1.03,1.13,1.15,1.55,1.72 and 2.26 times of the soil background of Shanxi province.The results of single factor pollution index showed that there was moderate pollution of Hg,slight pollution of Cd,Cu,Ni,Pb,Zn and Cr,and no pollution of As in farmland soils in Shouyang county.The mean PLI of eight heavy metals in all the sample points was 1.09,which was categorized as slight pollution.The average RI was 151.47 which represented a moderate ecological risk and mainly caused by Hg and Cd,other metals were in low risk.The distribution of PLI and RI showed some spatial differences with high value area and low value area,but PLI and RI shared a similar spatial distribution.When the local physical and geographical conditions are basically the same,haze,coal combustion,coal production and agricultural production are the important resources of soil heavy metals in this area,and the behavior of farmers may be one of the reasons for heavy metal pollution and ecological risk in some plots,which should be paid attention to.
作者
韩晋仙
李二玲
班凤梅
HAN Jin-xian;LI Er-ling;BAN Feng-mei(Department of Resources and Environment,Shanxi University of Finance and Economics,Taiyuan Shanxi 030006;College of Environment and Planning/Institute of Sustainable Development in Agriculture and Rural Area,Henan University,Kaifeng Henan 475004)
出处
《中国土壤与肥料》
CAS
CSCD
北大核心
2020年第6期246-253,共8页
Soil and Fertilizer Sciences in China
基金
国家自然科学基金项目(41971222)
教育部人文社会科学重点研究基地重大项目(15JJDZONGHE008)
河南省自然科学基金项目(182300410144)
河南大学一流学科创新团队培育项目(2018YLTD16)。
关键词
重金属
耕地土壤
污染
空间分布
潜在生态风险
常规农业村
heavy metal
farmland soils
pollution
spatial distribution
potential ecological risk
conventional agriculture villages
