湘东北典型河源区土壤重金属环境地球化学基线及污染评价  

Environmental geochemistry baseline and pollution assessment of soil heavy metals in typical river source area of northeastern Hunan Province

作　　者：杨振宇 廖超林[1] 李毅 邹炎 谢伍晋 陈晓威 张驭飞 YANG Zhen-yu;LIAO Chao-lin;LI Yi;ZOU Yan;XIE Wu-jin;CHEN Xiao-wei;ZHANGYu-fei(College of Resources,Hunan Agricultural University,Changsha 410128,China;New Rural Development Institute,Hunan Agricultural University,Changsha 410128,China)

机构地区：[1]湖南农业大学资源学院,湖南长沙410128 [2]湖南农业大学新农村发展研究院,湖南长沙410128

出　　处：《中国环境科学》2023年第8期4154-4163,共10页China Environmental Science

基　　金：国家自然科学基金项目(41571211);湖南省高校科研重点项目(15A085)。

摘　　要：选择湘东北典型河源区采集表层土壤样品共87件,分析了土壤重金属(Cd、Pb、Cr、Hg和As)的分布特征,采用参比元素标准化法和累积频率曲线法确定5种重金属的环境地球化学基线,并分别评价了以环境地球化学基线和环境背景值为基准的环境污染现状.结果表明:土壤Cd、Pb、Cr、Hg和As的含量平均值分别为0.197,41.065,130.512,0.294,11.633mg/kg;土壤Cd、Pb、Cr、Hg和As的环境地球化学基线值分别为0.196,41.065,126.301,0.283,9.931mg/kg;基于环境地球化学基线值进行的污染评价结果表明,湘东北典型河源区土壤79.31%的点位综合污染指数介于1.0~2.0,处于轻度污染等级,5种重金属单因子污染指数均值均小于1,处于无污染等级;环境地球化学基线确定了空间小尺度区域的评价基准,可弥补因基准值缺失而导致其评估结果界定模糊的不足.A total of 87 surface soil samples were collected from typical river source areas in northeast Hunan Province,and the distribution characteristics of soil heavy metals(Cd,Pb,Cr,Hg and As)were analyzed.The environmental geochemical baselines of five heavy metals were determined by the standardized method of reference elements and the cumulative frequency curve method,and the environmental pollution status was evaluated with the environmental geochemical baselines and environmental background values,respectively.The mean values of soil Cd,Pb,Cr,Hg and As were 0.197,41.065,130.512,0.294,11.633mg/kg,respectively.The environmental geochemical baseline values of soil Cd,Pb,Cr,Hg and As were 0.196,41.065,126.301,0.283,9.931.The pollution evaluation results based on the environmental geochemical baseline values show that 79.31% of the points in the typical river source area of northeast Hunan have a comprehensive pollution index ranging from 1.0 to 2.0,which is in the mild pollution level,and the pollution indexes of the five heavy metals are all less than 1,which is in the non-pollution level.The environmental geochemical baseline determines the evaluation benchmark for small-scale spatial areas,which can compensate for the pollution caused by the lack of baseline values.The environmental geochemical baseline determines the spatial small-scale regional evaluation benchmark,which can make up for the ambiguity of its assessment results due to the lack of benchmark values.

关 键 词：水源地 环境地球化学基线 土壤重金属 污染评价 

分 类 号：X53[环境科学与工程—环境工程]