土壤活性组分界面重金属同位素分馏行为研究进展OA北大核心CSTPCD

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 still 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.