广西贵港柑桔产区土壤重金属污染及生态风险评价  

Soil Heavy Metals Pollution and Ecological Risk Assessment in Citrus Production Areas of Guigang,Guangxi Province

作　　者：单志强 石少明[1] 马荣锴 杨小兰 SHAN Zhi-qiang;SHI Shao-ming;MA Rong-kai;YANG Xiao-lan(Liu zhou Vocational&Technical College,Liuzhou,Guangxi 545000,China;China Nonferrous Guilin Mineral Geological Research Institute Co.,Ld.,Guilin,Guangxi 541004,China)

机构地区：[1]柳州职业技术学院环境与食品工程学院,广西柳州545000 [2]中国有色桂林矿产地质研究院有限公司,广西桂林541004

出　　处：《四川环境》2020年第4期136-141,共6页Sichuan Environment

摘　　要：以广西贵港柑桔产区土壤为研究对象,分析了土壤中As、Hg、Cd、Cr、Cu、Sc、Pb、Zn 8种重金属含量及污染特征,基于农用地土壤污染评价标准(GB15618-2018),利用潜在生态危害指数法评价了该产区重金属的综合潜在生态风险。结果表明:Cr、Ni、Cu、Zn、As、Hg、Pb 7种元素含量均值低于土壤污染风险筛选值,Cd元素含量均值(1.22mg/kg)高于风险筛选值(0.3mg/kg)。Pb、Zn元素与Hg、Ni元素各自具有相似的空间分布规律,Cd元素含量有从中心向四周扩散的趋势。Cd元素处于较强的风险水平,很强与极强级别样本所占比例分别为17.5%和45%。Hg元素中度、强风险级别占比分别为39.5%、29.5%,说明该研究区土壤中Cd、Hg元素污染较严重。综合潜在风险指数RI均值为342.4,属于强生态风险,主要受Cd、Hg元素污染影响。To characterize the pollution and potential ecological risk from heavy meals in soil of farmland in Guigang County,The content and pollution characteristics of eight heavy metals(As,Hg,Cd,Cr,Cu,Sc,Pb and Zn) in the soil of Citrus producing area in Guigang,Guangxi were analyzed.Based on the Soil Environmental Quality Risk Control Standards for Soil Contamination of Agricultural Land(GB15618-2018),The comprehensive potential ecological risk of heavy metals in this area were evaluated by the potential ecological hazard index method.The results showed that the concentrations(mea valve) of Cr,Ni,Cu,Zn,As,Hg and Pb were lower than the soil pollution risk screening values(RSV) among all the soil heavy metals in the study region.The average content of Cd(1.22 mg/kg) is higher than the risk screening value(0.3 mg/kg).The elements of Pb and Zn have a similar spatial distribution laws with Hg and Ni,Cd element concentration has a tendency which spread from heart to surrounding.Cd concentration was higher than RSV,it was at a strong risk level,the proportion of strong and very strong samples were 17.5% and 45%,respectively.The proportion of moderate and strong risk levels of Hg were 39.5 % and 29.5 %, respectively, which indicated that the Cd and Hg contamination in the research area was more serious.Furthermore,The average of the potential risk index(RI) is 342.4 in this area,which indicates a high level of potential risk,mainly due to the high levels of Cd and Hg contamination.

关 键 词：重金属污染 生态风险 反距离权重法 

分 类 号：X53[环境科学与工程—环境工程]