2026-10-15T08:24:56Z https://data.mendeley.com/oai

oai:data.mendeley.com/74jvszf5km.1 2025-12-19T15:33:04Z

Wu, Xinyue Depth-dependent fate of antimony in sediment is governed by microbially driven iron transformation under redox fluctuation Mendeley Data Antimony (Sb) is a highly ecotoxic metalloid that frequently coprecipitates with hydroxyl ferric sulfate minerals (e.g., schwertmannite) in mining environments. The depth-dependent release patterns and governing mechanisms of Sb in sediments under redox fluctuation are not yet clear, which limits a systematic understanding of its biogeochemical behavior and associated environmental risks. This study constructed sediment column systems with different Sb doping levels, and simulated a cycle of 40-day flooding and 20-day drying treatment. Results showed that Sb migration was controlled by a microbial-mediated Fe-Sb coupling cycle with distinct vertical differentiation. During flooding, strong deep-layer reducing conditions drove reductive dissolution and Sb(III) accumulation. Consequently, dissolved Sb increased with depth, reaching 59.0 μg/L (16.3% Sb(III)) in deep layer (15 cm) in high-Sb treatment (0.10Sb_Sch: 674 mg Sb/kg sediment). This process was dominated by iron-reducing bacteria (Bacteroidales), with specific taxa like Acidimicrobiia facilitating Sb(V) reduction. After drying, surface aerobic conditions triggered the proliferation of iron-oxidizing bacteria (Gallionellaceae), promoting Fe oxidation and Sb re-fixation. In contrast, deep sediments (15 cm) maintained high Sb mobility (18.91 μg/L in 0.10Sb_Sch treatment) due to persistent reducing bacteria (Bacillota, Thermodesolufobacteria). This study revealed the hierarchical regulation of microbial-mediated Fe-Sb coupling mechanism under hydrological fluctuation, deepened the understanding of Sb environmental behavior, and provided theoretical basis for the prevention, control and restoration of Sb pollution risk in mining areas. Sedimentary Geochemistry Antimony Microorganism Dataset doi:10.17632/74jvszf5km.1 oai:data.mendeley.com/74jvszf5km.1 Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0 https://data.mendeley.com/datasets/74jvszf5km 2025-12-19T15:33:04Z