三峡库区典型农业区土壤重金属污染特征及风险评价  

Characterization and risk assessment of heavy metal pollution in agricultural soils in Three Gorge Reservoir Area

作　　者：王金霞 李谢玲[2] 何清明[3] 陈玉成[1] 蔡庆[2] 罗乐[2] 赵雪[2] Wang Jinxia;Li Xieling;He Qingming;Chen Yucheng;Cai Qing;Luo Le;Zhao Xue(Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment,Ministry of Education,Southwest University,Chongqing 400715,China;Chongqing Vocational Institute of Engineering,Chongqing 400037,China;Taizhou University,Taizhou,225300,China)

机构地区：[1]西南大学三峡库区生态环境教育部重点实验室,重庆400715 [2]重庆工程职业技术学院,重庆400037 [3]泰州学院,泰州225300

出　　处：《农业工程学报》2018年第8期227-234,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家重点研发计划(2017YFD0801004);重庆市教委科学技术研究项目(KJ1503302);江苏省高校自然科学研究面上项目(15KJD610005)

摘　　要：为了解三峡库区农业区土壤重金属污染现状及环境风险水平,该文以重庆市8个典型农业区县(铜梁、云阳、万州、丰都、城口、垫江、南川和江津)土壤为研究对象,共采集表层(0~20 cm)土壤样品160个,依照《土壤环境监测技术规范(HJ/T 166-2004)》和《土壤环境质量标准GB 15618-1995》分析了土壤样品中8种重金属(As、Cd、Cr、Cu、Hg、Ni、Pb和Zn)的含量,比较了不同区县8种重金属污染现状及差异,应用地积累指数法和潜在生态风险指数法探讨了研究区土壤重金属的累积特征及潜在生态风险等级。结果表明:该研究区农业土壤8种重金属含量平均值均未超过《土壤环境质量标准GB 15618-1995》二级标准,与土壤背景值相比,Cd、Cr、Cu、Hg和Zn均具有极显著差异(P<0.01),As、Ni和Pb差异不显著,8个区县Cr均表现出极显著差异(P<0.01),城口区多种重金属均表现出极显著差异(P<0.01),8种重金属地累积指数平均值均小于0,研究区土壤受重金属污染水平为未污染等级,单个重金属潜在生态风险顺序为Hg>Cd>As>Hg>Cu>Ni>Cr>Zn,Hg元素潜在生态风险指数平均值为43.8>40,属中等生态风险等级,其余元素生态风险指数值均小于40,属于低生态风险等级,8种重金属综合潜在生态风险指数平均值为108<135,为低生态风险等级。综合研究结果表明:三峡库区典型农业区土壤Cd、Cr、Cu、Hg和Zn具有一定程度的累积,且表现为多种重金属复合累积现象,Cr累积具有普遍性,Hg是影响三峡库区农业土壤综合潜在生态风险的主要元素,但研究区土壤重金属总体处于低生态风险水平。Over the past several decades,a large amount of agricultural production materials(such as chemical fertilizers,organic fertilizers,pesticides and agricultural films)has been used to increase the output of agricultural products.Therefore,the problems of soil pollution,especially heavy metal pollution in soils,have become problems.Those problems have exerted direct or indirect adverse effects on food safety,and health of human and ecosystem.Therefore,the problem of heavy metal pollution in agricultural soils has become a research hot spot in environmental studies and has since received more attention.Chongqing is an important agricultural production base in the Three Gorges Reservoir Area.The environmental quality of soils in Chongqing area directly affects the food safety and health of the local residents.Although there have been some studies on the quality of agricultural soils,few studies have investigated the status of heavy metal pollution in the agricultural areas of Chongqing.In order to understand the status of heavy metal pollution and the level of its environmental risk in typical agricultural areas in Chongqing,160 surface soil samples(0-20 cm)were collected from the farm field of eight agricultural areas(Tongliang,Yunyang,Wanzhou,Fengdu,Chengkou,Dianjiang,Nanchuan and Jiangjin)based on the"Technical Specifications for Soil Environmental Monitoring(HJ/T 166-2004)".The concentrations of eight heavy metals(As,Cd,Cr,Cu,Hg,Ni,Pb and Zn)in these soil samples were analyzed according to the"Environmental quality standard for soils GB 15618-1995".The status and differences in pollutions of these weight heavy metals among various regions were compared.In addition,geo-accumulation index and potential ecological risk index were used to evaluate the accumulation characteristics and potential environmental risk levels of heavy metals in the studied regions.The results showed that the average contents of As,Cd,Cr,Cu,Hg,Ni,Pb and Zn in the soils of the typical agricultural areas in Chongqing were respectively 6.110,0.1

关 键 词：土壤 重金属 污染 三峡库区 农业区 风险评价 

分 类 号：S2[农业科学—农业工程]