鳞片岩
针铁矿
铁酸盐
矿物
土壤水分
磁铁矿
化学
环境化学
矿物学
斯沃特曼矿
粘土矿物
赤铁矿
地质学
土壤科学
古生物学
有机化学
吸附
作者
Luiza Notini,Katrin Schulz,L. Joëlle Kubeneck,Andrew R. C. Grigg,Katherine A. Rothwell,Giulia Fantappiè,Laurel K. ThomasArrigo,Ruben Kretzschmar
标识
DOI:10.1021/acs.est.3c00434
摘要
Iron minerals in soils and sediments play important roles in many biogeochemical processes and therefore influence the cycling of major and trace elements and the fate of pollutants in the environment. However, the kinetics and pathways of Fe mineral recrystallization and transformation processes under environmentally relevant conditions are still elusive. Here, we present a novel approach enabling us to follow the transformations of Fe minerals added to soils or sediments in close spatial association with complex solid matrices including other minerals, organic matter, and microorganisms. Minerals enriched with the stable isotope 57Fe are mixed with soil or sediment, and changes in Fe speciation are subsequently studied by 57Fe Mössbauer spectroscopy, which exclusively detects 57Fe. In this study, 57Fe-labeled ferrihydrite was synthesized, mixed with four soils differing in chemical and physical properties, and incubated for 12+ weeks under anoxic conditions. Our results reveal that the formation of crystalline Fe(III)(oxyhydr)oxides such as lepidocrocite and goethite was strongly suppressed, and instead formation of a green rust-like phase was observed in all soils. These results contrast those from Fe(II)-catalyzed ferrihydrite transformation experiments, where formation of lepidocrocite, goethite, and/or magnetite often occurs. The presented approach allows control over the composition and crystallinity of the initial Fe mineral, and it can be easily adapted to other experimental setups or Fe minerals. It thus offers great potential for future investigations of Fe mineral transformations in situ under environmentally relevant conditions, in both the laboratory and the field.
科研通智能强力驱动
Strongly Powered by AbleSci AI