碳酸盐岩风化成土过程重金属的迁移富集特征——以华南典型地区为例  

Migration and enrichment characteristics of heavy metals during the weathering and soil-forming process of carbonate rocks:A case study of typical areas in South China

作　　者：施小学 孙乾迎 卢阳 吴文成 陈伟杰 SHI Xiao-xue;SUN Qian-ying;LU Yang;WU Wen-cheng;CHEN Wei-jie(Department of Resources and Environment,Anhui University,Hefei 230601,China;South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou 510655,China)

机构地区：[1]安徽大学资源与环境专业,安徽合肥230601 [2]生态环境部华南环境科学研究所,广东广州510655

出　　处：《中国环境科学》2025年第4期2063-2074,共12页China Environmental Science

基　　金：国家自然科学基金资助项目(42177183)。

摘　　要：以华南碳酸盐岩地区水田、旱地2种典型农用地风化土壤剖面为研究对象,通过Pb同位素组成对土壤重金属进行溯源,并系统分析了8种常见重金属在农田土壤剖面中的垂直分布及影响因素.结果表明,母岩风化是研究区土壤重金属的主要来源;两个剖面中重金属含量均高于土壤背景值(0.056mg/kg),Cd偏向于在表层(0.49~2.15mg/kg)与中层(0.75~1.87mg/kg)富集,其他元素均偏向于在中层富集.土壤理化性质、矿物组成,以及氧化还原条件变化对重金属迁移具有重要影响.碳酸盐岩风化过程造成了研究区土壤剖面中重金属元素的次生富集,水田剖面的淋溶作用对重金属的迁移富集影响更大.The weathered soil profiles were taken as the research objects from paddy and upland fields,which are typical agricultural lands in the carbonate rock regions of South China.The sources of soil heavy metals were traced via Pb isotope composition,and the vertical distribution and influencing factors of eight common types of heavy metals in the farmland soil profiles were systematically analyzed.The results revealed that the weathering of parent rocks was the main source of soil heavy metals in the study area,and the contents of heavy metals in the two profiles were found to be higher than the soil background value(0.056mg/kg).The enrichment of Cd tended to occur in the surface layer(0.49~2.15mg/kg)and the middle layer(0.75~1.87mg/kg)of the soil profiles,while that of the other elements tended to occur in the middle layer.The physicochemical properties and the mineral compositions of the soils,as well as the changes in the redox conditions exerted important impacts on the migration of heavy metals.The secondary enrichment of heavy metals in the soil profiles from the study area was attributed to the weathering process of carbonate rocks,while the impact of the leaching process on the migration and enrichment of heavy metals was more significant in the profile from the paddy field.

关 键 词：碳酸盐岩 农田土壤剖面 重金属 垂向迁移 影响因素 

分 类 号：X53[环境科学与工程—环境工程]