贵州喀斯特山区锑冶炼厂对农业土壤污染特征的影响及风险评价  

Distribution Characteristics and Risk Assessment of Heavy Metals in Agricultural Soils in An Abandoned Antimony Smelter in Guizhou Karst Areas

作　　者：刘灵飞[1] 龙健[1] 万洪富[2] 李娟[3] 

机构地区：[1]贵州师范大学贵州省山地环境重点实验室,贵阳550001 [2]广东省生态环境与土壤研究所,广州510650 [3]贵州师范大学地理与环境科学学院,贵阳550001

出　　处：《土壤》2013年第6期1036-1047,共12页Soils

基　　金：贵州省科学技术基金项目(黔科合J字[2011]2046号);贵州省研究生教育教学改革研究课题项目(黔财教[2011]231号);贵州师范大学研究生教育管理创新基金项目(研2012(19)号);贵州省科技联合项目(黔科合J字LKS[2009]20号)资助

摘　　要：以贵州省晴隆县大厂镇喀斯特山区废弃锑冶炼厂周同的农田土壤为研究对象，研究了距离冶炼厂炯囱不同距离12个表层土壤样点和5个典型土壤剖面中重金属含量。结果表明表层土壤主要污染元素为Sb、Zn、Pb、Hg、As和Cu，分别是贵州省土壤背景值的58．58、11．96、7．99、7．45、6．70和1．60倍；土壤剖面中8种主要重金属元素垂直变化规律各异，不同层次重金属含量（Pb除外）均表现为：距离冶炼厂烟囱越近含量越高，平均含量由高到低依次为：Mn〉As〉Sb〉Cu〉Cr〉Pb〉Hg〉Cd，均明显高于全国土壤背景值的平均水平。其中，As、Cr、Mn和Hg平均含量差异较大，与对照相比，主要污染元素为Sb、Hg和As，Hg和As分别为国家土壤环境质量Ⅱ级标准的4．7倍、4．4倍；其次是Cd和Cu，分别为周家II级标准的3．0倍、2．7倍。相关分析和聚类分析表明，土壤主要受重金属Cr、Cd、Cu、Sb和As复合污染。采用单因子污染指数和内梅罗综合污染指数法对该地区农田土壤进行了环境风险评价，各层次Cr、Cd、Cu和As含量均超标，污染严重，综合污染指数在1．21～14．83之间，以重度污染为主；耕作层污染程度由高到低顺序为：大厂村（冶炼厂）〉中心街村〉碧康组〉田坝组，均属于重度污染，表层污染土壤（0～20cm）种植农作物存在一定的风险。This research was conducted to determine the concentrations of heavy metal in farmland of a typical smelters in Guizhou Province. Soil samples were collected from agricultural soils including 12 surface layer soils and five typical profiles at different distances from the smelter chimney in Dachang Town of Qinglong County. Results showed that the mean concentrations of Sb, Zn, Pb, Hg, As and Cu in surface layer soils were 58.58, 11.96, 7.99, 7.45, 6.70 and 1.60 times of soil background values of Guizhou, respectively. The vertical variation of heavy metals （except Pb） in soil profiles were significantly different and the average content of heavy metals in soils was followed the sequences： Mn〉As〉Sb〉Cu〉Cr〉Pb〉Hg〉Cd, which were all higher than the average level of the national soil background value, and more, the average content of As, Cr, Mn and Hg performed to have great differences, the main pollution elements Hg and As were 4.7 times and 4.4 times of the standard of national grade II, followed by Cd and Cu which were 3.0 times and 2.7 times, respectively. Correlation analysis and cluster analysis showed that soil was suffered from combined pollution of heavy metals, such as Cr, Cd, Cu, Sb and As, which were higher at all layers in soil profile in the light of SFPI and the top-layer （0-20cm）. However, certain risk to plant was present according to the assessment results of heavy metals with Single Factor Pollution Index（NCPI）. The pollution levels were followed the sequence： Dachang village〉Zhongxinjie village〉Bikang group and Tianba group, and the index was between 1.21 and 14.83.

关 键 词：喀斯特山区 锑矿 土壤剖面 重金属污染 风险评价 

分 类 号：S15[农业科学—土壤学] X53[农业科学—农业基础科学]