摘要
近年来,多接收电感耦合等离子体质谱仪(MC-ICP-MS)及分离纯化技术的发展使得精确测量重金属稳定同位素组成成为可能,大大促进了其在重金属污染物来源识别、土壤-植物系统重金属迁移和纳米颗粒环境行为示踪等方面的应用。但是,许多表生环境地球化学过程会引起不同程度的同位素分馏,从而模糊不同重金属储库的同位素指纹特征,使得对环境样品同位素组成的理解变得复杂,被称为“同位素分馏黑箱”。揭示同位素分馏黑箱对于重金属非传统稳定同位素的应用具有重大意义。尽管重金属在各种土壤活性组分界面反应过程中的重金属同位素分馏已有一些研究,但有关矿物结构发生同晶替代过程中的分馏机制尚不清楚,且存在许多不一致或矛盾的地方。本综述系统总结了典型重金属污染物Cd、Zn、Ni在土壤活性组分界面,尤其是铁锰氧化物矿物界面的同位素分馏行为和机制,并指出未来应关注的方向。相关研究的深入将加深对重金属污染物环境地球化学行为的理解,推进对土壤同位素分馏黑箱的理解和非传统稳定同位素在土壤重金属污染物溯源、示踪等过程中的应用,为土壤重金属污染的治理、修复和安全利用等提供科学依据和理论支撑。
Recently,advances in multi-collector inductively-coupled-plasma mass spectrometry(MC-ICP-MS)and chemical separation and purification methods,have made it possible to accurately measure heavy metals isotope compositions,and thus greatly promote the application in tracing the sources of heavy metal pollutants,tracking the migration of heavy metals within soil-plant systems and understanding the environmental behaviors of nanoparticles.However,many geochemical processes in surficial environments can cause isotopic fractionation,obscuring the isotopic fingerprints of different heavy metal reservoirs and thus obscure complicating the understanding of the isotopic compositions of environmental samples,which is called‘isotope fractionation black box'.Therefore,it is of great significance to unveil the isotope fractionation black box in the applications of non-traditional stable isotopes.While some studies have reported heavy metal isotopic fractionations during the interfacial reaction processes with various soil active components,the fractionation mechanisms are stll unclear for metal isomorphous substitution in minerals and many inconsistencies or contradictions exist.This review systematically summarizes the isotope fractionation behaviors and mechanisms of typical heavy metals such as Cd,Zn and Ni at the interfaces of soil active components,especially at Fe-Mn oxide minerals,and points out directions of future attention.This will deepen the understanding of the environmental geochemical behavior for heavy metal pollutants,promote the understanding of soil isotope fractionation black box and the application of non-traditional stable isotopes in tracing soil heavy metal pollutant behaviors,and provide scientific basis and theoretical support for the treatment,remediation and safe utilization of heavy metal polluted soils.
作者
殷辉
殷明
严欣然
全越洋
涂书新
YIN Hui;YIN Ming;YAN Xinran;QUAN Yueyang;TU Shuxin(College of Resources and Environment,Huazhong Agricultural University,Wuhan,Hubei 430070;Shiyan Ecological Environment Monitoring Center of Hubei Provincial Department of Ecology and Environment,Shiyan,Hubei 442000)
出处
《核农学报》
CAS
CSCD
北大核心
2024年第3期603-611,共9页
Journal of Nuclear Agricultural Sciences
基金
国家自然科学基金项目(42077015)。
关键词
土壤
界面反应
重金属稳定同位素
吸附
同晶替代
soil
interfacial reactions
heavy metal stable isotopes
adsorption
isomorphous substitution
