湘西凤凰铅锌矿区典型土壤剖面中重金属分布特征及其环境意义  

Spatial distribution and ecological significance of heavy metals in typical soil profiles in the Fenghuang Lead-Zinc mining area,Western Hunan Province

作　　者：姬艳芳[1,2] 李永华[1] 杨林生[1] 孙宏飞[1,2] 王五一[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院研究生院,北京100039

出　　处：《环境科学学报》2009年第5期1094-1102,共9页Acta Scientiae Circumstantiae

基　　金：中国科学院知识创新工程重要方向性资助项目(No.KZCX3-SW-437);国家自然科学基金资助项目(No.40571008)~~

摘　　要：为探讨铅锌矿区土壤中重金属的来源、分布及迁移特征,在凤凰铅锌矿区分别选取楠木冲新开井矿口自然土壤剖面(A)、桐木洞老矿井矿口自然土壤剖面(B)和矿渣下覆土壤剖面(C)3个典型剖面,结合剖面中的新鲜母岩及矿区的耕层土壤、水稻、矿石、废矿、矿渣等样品,对区域内土壤剖面中重金属的迁移分布特征进行了调查分析.结果发现,A剖面中重金属明显在底层富集,而B剖面中重金属则呈现显著的表层富集趋势,C剖面中重金属表层富集的趋势相对较弱.不同剖面中重金属元素按照淋溶难易排序依次为:Zn>Cd>Pb≈Hg.除Pb的含量表现为为C剖面>B剖面>A剖面外,3个剖面中Zn、Hg、As、Cd的含量由高到低依次为:B剖面>C剖面>A剖面.以上结果表明,凤凰铅锌矿区土壤剖面重金属的来源、迁移和富集既与原生地质环境有关,更与人类采矿活动及开采历史密切相关.人为大规模的采矿活动对重金属在表层土壤中的积累起到主要作用,矿渣的随意堆砌也加剧了土壤剖面中重金属的污染.In order to study the origins, distribution and migration characteristics of lead, zinc, mercury, arsenic and cadmium, three typical soil profiles from the Fenghuang Lead-Zinc mining area, western Hunan province, i.e. the natural soil profile near the new mine entrance-A, the natural soil profile near the old mine entrance-B and the soil profile covered with slag-C were taken and compared with fresh parent rocks under two natural soil profiles, fourteen plough horizon soils and rice samples, some fresh ores, spent ores and slag from the area.. The results show that heavy metals accumulate strongly on the surface of profile B but on the bottom of profile A. For profile C, the accumulation trend of heavy metals is less obvious. The leaching ability of different metals follows the order Zn 〉 Cd 〉 Pb ≈ Hg. The concentration of Pb is highest in profile C and lowest in profile A whereas the concentrations of other metals are highest in profile B and lowest in profile A. Taken together, the results suggest that sources, transportation and accumulation of these heavy metals in the investigated area are not only related to the original geology, but also strongly related to human mining activities and mining history. Extensive human mining activities make a major contribution to the accumulation of heavy metals in topsoil while the random disposal of slag aggravates heavy metal pollution over the whole soil profile.

关 键 词：铅锌矿区 重金属 土壤剖面 分布 迁移深度 

分 类 号：X53[环境科学与工程—环境工程]