青海民和-海石湾一带土壤重金属异常成因研究  

A study of the origin of heavy metal anomaly in soil of Minhe-Haishiwan area,Qinghai Province

作　　者：章巧秋[1] 谢正苗[1] 姬丙艳 张亚峰 唐俊红[1] 

机构地区：[1]杭州电子科技大学,浙江杭州310018 [2]青海省第五地质矿产勘查院,青海西宁810012

出　　处：《岩石矿物学杂志》2011年第6期1125-1131,共7页Acta Petrologica et Mineralogica

基　　金：国家自然科学基金资助项目(40973076)

摘　　要：青海省多目标区域地球化学调查发现,民和-海石湾一带的狭长谷地沿109国道两侧分布的土壤中存在以Cd、Pb、Hg、Cr等重金属元素为主组成的综合异常。空间上各异常元素套合较好,而且综合异常面积较大,异常元素衬度较高。经相关分析,Cr元素与土壤常量组分显著相关,与SiO2含量呈负相关关系,同时,Cr元素水平剖面上城区含量明显高于其他地方,垂向剖面上呈现元素表层略微富集的现象;Cd与有机碳之间存在显著性相关关系,与TFe2O3不存在显著性相关关系;Pb元素在80 cm以上的土壤中,异常区土壤中的含量明显高于非异常区,Pb异常基本存在于表层土壤中;Hg元素含量表层富集明显,城区土壤中的Hg含量远高于其他地方。研究结果表明,人为源输入是导致该地区Cd、Pb、Hg异常的主要因素,而Cr元素异常的形成具有双成因性质,在较高自然背景上产生了人为源叠加。因此,加强异常区工业"三废"的控制和管理,是防止异常面积扩大的有效措施。This paper reports some results of multi-purpose geochemical mapping in Qinghai Province.Soil heavy metal anomalies of such elements as Cd,Pb,Hg and Cr were detected in the narrow valley of Minhe and Haishiwan,along Road 109.The heavy metal anomalies exhibit features of relatively large anomalous area and high thresholds of anomalous elements.The results of correlation analysis show that Cr is significantly associated with soil constant components and negatively related to SiO2.Cr is slightly concentrated in the top layer of soil in vertical section while urban areas have considerably higher level of Cr along the horizontal section.Cd is evidently associated with organic carbon,but there exists no such obvious correlation between Cd and TFe2O3.Beyond the soil depth of 80 cm,the content of Pb in the anomalous area is obviously higher than that in other areas.Pb anomaly basically exists at the surface of the soil.Hg is obviously concentrated at the surface of soil,while in the urban area it exists at the higher level.The results indicate that anthropogenic input is the main factor responsible for the formation of anomalies of Cd,Pb and Hg.The anthropogenic input increases the content of Cr in the high natural background.Therefore,we must control and manage the industrial ＂three wastes＂ in the anomalous area to prevent the expansion of the soil heavy metal anomaly.

关 键 词：多目标区域地球化学调查 土壤 元素异常 土壤质地 

分 类 号：P579[天文地球—矿物学] X53[天文地球—地质学]