Cadmium and zinc isotope compositions indicate metal sources and retention mechanisms in different soil particle size fractions
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Soil particle size may significantly affect metal distribution and stable isotopic behavior. Here, two soils were separated into four particle size fractions, namely fine sand, silt, fine silt, and colloidal particles and used to determine cadmium (Cd) and zinc (Zn) concentrations and isotope compositions. Concentrations of Cd and Zn were generally enriched in the finer particles and positively correlated with the iron (Fe) and manganese (Mn) oxide contents. However, Cd concentration in the fine sand was higher than in the silt fraction due to the higher soil organic matter contents in the former particle fraction. The maximum δ114/110Cd value was found in the colloidal particles (−0.02 and 0.01‰) of both soils while the minimum was in the silt particles (−0.12 and single bond0.06‰). Incorporation into the mineral lattice of Fe and Mn oxides is suggested to explain the slight enrichment of heavy Cd isotopes in the colloidal fraction. The similar δ66Zn values of the four particle fractions (0.20–0.29‰ with a mean of 0.25‰) indicate similar Zn sources in different particle sizes. Metal isotopic fingerprint of different soil particle size fractions provides further insight into underlying metal retention mechanisms within soil micro-zones and helps in tracing metal sources and biogeochemical processes.
Date Issued
2024-01-05
Date Acceptance
2023-09-12
Citation
Journal of Hazardous Materials, 2024, 461
ISSN
0304-3894
Publisher
Elsevier BV
Journal / Book Title
Journal of Hazardous Materials
Volume
461
Copyright Statement
Copyright © Elsevier Ltd. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
Identifier
http://dx.doi.org/10.1016/j.jhazmat.2023.132560
Publication Status
Published
Article Number
132560
Date Publish Online
2023-09-16