铅冶炼场地土壤重金属污染空间分布和迁移特征
Migration and distribution characteristics of soil heavy metal(loid)s at a lead smelting site
Chuxuan Li, Mu Li, Jiaqing Zeng, Shanxin Yuan, Xinghua Luo, Chuan Wu, Shengguo Xue*
https://doi.org/10.1016/j.jes.2023.02.007
摘要
有色冶炼场地重金属污染是普遍存在的环境问题，直接影响土地再开发和安全利用。本文选择典型废弃铅冶炼场地，从元素总量和赋存形态角度研究土壤重金属的空间分布和迁移特征，结果表明：冶炼场地重金属污染物主要为Pb、As、Cd和Zn，表层土壤污染占比分别为99.5%、98.9%、85.3%和72.4%。冶炼场地土壤重金属分布表现出较强的空间异质性，与原企业生产功能分区关系密切。重金属从土壤表层向下迁移，Pb、As、Cd的污染深度超过5米。随着土壤深度的增加，As、Cd和Zn的浸出含量显著降低，弱酸提取态比例相应降低，而残渣态比例逐步增加。土壤As主要以残渣态和可还原态存在，深层土壤Cd的浸出含量和弱酸提取态比例较高，表明Cd具有较强的迁移性。重金属元素在土壤中的迁移性：Cd > Zn > Pb > As，研究结果对有色冶炼场地环境管理和污染修复策略拟定提供重要科学依据。
亮点
有色冶炼场地土壤重金属元素分布具有较强的空间异质性，重金属在土壤中的迁移性：Cd > Zn > Pb > As。
Abstract
Heavy metal(loid)s contamination is a constant issue at smelting sites. It is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental management and remediation strategies of non-ferrous smelting sites. In this study, 203 soil samples from 57 sites were collected in a typical lead smelting site. The findings demonstrated that there were significant Pb, Zn, Cd, and As contamination in soil samples. The spatial distribution of heavy metal(loid)s showed strong spatial heterogeneity, the contaminated soil areas of Pb, As, Cd, and Zn were 99.5%, 98.9%, 85.3%, and 72.4%, respectively. Pb, Cd, and As contamination of the soil reached a depth of 5 m, which migrated from the surface to deep soil layers. The leaching contents of Zn, Pb, and As decreased obviously in 3-4 m soil layer, but the leaching content of Cd was still high, which indicated the high migration of Cd. With the increase of depth, the proportion of acid soluble fraction of heavy metal(loid)s decreased, and the residual fraction increased. The acid soluble fraction of Cd accounted for a higher proportion, and As mainly existed in reducible and residual fractions in soil. According to the calculation of the migration factor, the migration of heavy metal(loid)s in soils were ordered as Cd > Zn > Pb > As. The outcomes are advantageous for risk reduction and site remediation for non-ferrous metal smelting sites.
作者简介
第一作者
李楚璇，中南大学环境科学与工程2021级博士生，研究方向为有色冶炼场地重金属污染修复，在Journal of Hazardous Materials、Transactions of Nonferrous Metals Society of China、Journal of Environmental Sciences、Journal of Soils and Sediments等期刊发表论文6篇，授权国家发明专利1项。
通讯作者
薛生国，中南大学二级教授、湖南省优秀博士学位论文指导教师、国家重点研发计划项目首席科学家、矿冶场地生态修复创新群体负责人；中国生态学会污染生态专业委员会副主任、中国硅酸盐学会冶金渣专业委员会副主任。持续开展“场地污染阻控-土水协同修复-土壤功能重构-生态景观再造”全链条研究，努力突破矿冶场地生态修复技术瓶颈，推动大宗工业固体废物回归自然。在国内首次报道锰超富集植物垂序商陆，丰富了污染环境修复的种质资源；对接国家重大战略需求，研发可复制推广的有色冶炼场地土壤-地下水水协同修复技术；针对大宗工业固体废物处置的世界难题，创造性提出“物理-化学-生物协同生态处置”新思路，引领国际固体废物土壤化处置研究方向。主持国家重点研发计划项目、国家基金重点项目、国家环保行业专项、国家基金区域创新项目等 20 余项。编制《赤泥堆场原位生态修复技术规范》《赤泥堆场原位生态修复工程技术标准》《矿山生态修复技术规范（第3部分：金属矿山）》《污染场地地下水修复技术可行性评估技术规范》《有色冶炼场地土壤-地下水重金属污染协同修复与管控技术指南》等国家行业或地方标准10项。以通讯作者在 Chemical Engineering Journal、Journal of Hazardous Materials、Journal of Cleaner Production、《环境科学》、《生态学报》、《土壤学报》等发表论文 100余 篇，兼任Land Degradation & Development、Journal of Central South University等期刊客座编辑。主编国家出版基金专著 Soil Genesis and Ecological Rehabilitation in Bauxite Residue Disposal Areas、《赤泥堆场成土过程与环境风险管理》《污染环境修复实践与案例》等著作5部，授权国家发明专利20件，担任5次国际学术会议执行主席。
原文链接
https://www.sciencedirect.com/science/article/pii/S1001074223000517
引用格式
Chuxuan Li, Mu Li, Jiaqing Zeng, Shanxin Yuan, Xinghua Luo, Chuan Wu, Shengguo Xue, 2024. Migration and distribution characteristics of soil heavy metal(loid)s at a lead smelting site. J. Environ. Sci. 135, 600-609.
