雅鲁藏布江流域不同利用类型土壤重金属积累特征与源解析  

Characteristics and Source Analysis of Heavy Metal Accumulation in Different Soil Types of the Yarlung Zangbo River Basin

作　　者：朱静丹 刘国一 薛会英[3] ZHU Jingdan;LIU Guoyi;XUE Huiying(Institute of Xizang Plateau Ecology,Xizang Agricultural and Animal Husbandry University,Nyingchi 860000,China;Institute of Agricultural Resources and Environment,Academy of Agriculture and Animal Husbandry,Xizang Autonomous Region,Lhasa 850000,China;College of Resources and Environment,Xizang Agricultural and Animal Husbandry University,Nyingchi 860000,China)

机构地区：[1]西藏农牧学院高原生态研究所,西藏林芝860000 [2]西藏自治区农牧科学院农业资源与环境研究所,西藏拉萨850000 [3]西藏农牧学院资源与环境学院,西藏林芝860000

出　　处：《环境科学与技术》2024年第11期78-87,共10页Environmental Science & Technology

基　　金：西藏科技厅生态专项(XZ202201ZD0005G03)。

摘　　要：为了解雅鲁藏布江流域不同利用类型土壤重金属元素含量、分布、污染程度及源解析,文章在朗县-米林段农田和林地各设置21个采样点,共采集126份土壤样品,研究农田和林地土壤重金属含量、分布规律、污染程度和污染来源的差异性。结果表明:(1)雅鲁藏布江流域农田和林地土壤中Cd元素含量均值超过西藏土壤环境背景值,且农田土壤中Cd含量均值高于林地土壤,Cr、Co、Ni、Cu、Zn、As、Pb和Sb元素含量均值均未超过西藏土壤环境背景值;(2)农田和林地土壤中Co、Ni、Zn、As和Cd的含量存在显著差异(P<0.05);(3)农田和林地土壤中各重金属元素含量均呈段状空间分布格局;(4)农田土壤中Cd元素的地累积指数高于林地土壤,其潜在生态风险指数结果表明农田和林地分别处于中度生态风险和低生态风险水平,Cd元素是引起农田和林地潜在生态风险危害的主要风险因子;(5)农田土壤重金属主要来源于交通运输源(43.05%)、自然源(31.32%)及自然与农业活动混合源(25.63%);林地土壤重金属主要来源于交通运输源(44.29%)、自然源(34.79%)以及自然与生活垃圾混合源(20.92%)。To understand different types of soil heavy metal content,distribution,pollution degree and source analysis of Yarlung Zangbo River Basin,21 sampling points were set in farmland and woodland of Lang County-Milin,and a total of 126 soil samples were collected to analyze the soil heavy metal content,distribution,pollution degree and the difference of pollution source.The results show that the mean content of Cd elements in farmland and forest soil in the Yarlung Zangbo River Basin exceeded the background value of Tibetan soil,and the mean Cd content in farmland soil was higher than that of woodland soil,and the mean content of Cr,Co,Ni,Cu,Zn,As,Pb and Sb did not exceed the background value of Tibetan soil.There is a significant difference of Co,Ni,Zn,As,and Cd content in farmland and woodland(P<0.05).The content of heavy metal elements in the soil of farmland and woodland shows a segmented spatial distribution pattern.The land accumulation index of Cd elements in farmland soil is higher than that of woodland soil.The potential ecological risk index results indicate that farmland and woodland are at moderate and low ecological risk levels,respectively.Cd element is the main risk factor that causes the potential ecological risk and harm of farmland and woodland.Heavy metals in farmland soil mainly come from transportation sources(43.05%),natural sources(31.32%)and mixed sources of natural and agricultural activities(25.63%).Heavy metals in woodland soil mainly come from transportation sources(44.29%),natural sources(34.79%)and mixed sourc⁃es of natural and domestic waste(20.92%).

关 键 词：雅鲁藏布江流域 土壤 重金属 污染评价 源解析 

分 类 号：X53[环境科学与工程—环境工程]