Coupled iron cycling and organic matter transformation across redox interfaces

Nature Reviews Earth & Environment, Год журнала: 2023, Номер 4(9), С. 659 - 673

Опубликована: Авг. 24, 2023

Язык: Английский

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Mineral-Bound Trace Metals as Cofactors for Anaerobic Biological Nitrogen Fixation

Environmental Science & Technology, Год журнала: 2023, Номер 57(18), С. 7206 - 7216

Опубликована: Апрель 28, 2023

Nitrogenase is the only known biological enzyme capable of reducing N2 to bioavailable NH3. Most nitrogenases use Mo as a metallocofactor, while alternative cofactors V and Fe are also viable. Both geological bioinformatic evidence suggest an ancient origin Mo-based nitrogenase in Archean, despite low concentration dissolved Archean oceans. This apparent paradox would be resolvable if mineral-bound were for nitrogen fixation by diazotrophs. In this study, bioavailability Mo, V, was determined incubating obligately anaerobic diazotroph Clostridium kluyveri with Mo-, V-, Fe-bearing minerals (molybdenite, cavansite, ferrihydrite, respectively) basalt under diazotrophic conditions. The results showed that C. utilized mineral-associated metals express genes fix nitrogen, measured reverse transcription quantitative polymerase chain reaction acetylene reduction assay, respectively. secreted chelating molecules extract from minerals. As result microbial weathering, mineral surface chemistry significantly changed, likely due coating exudates metal extraction. These provide important support nitrogenase, profound implications coevolution biosphere geosphere.

Язык: Английский

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Biochar-mediated remediation of uranium-contaminated soils: evidence, mechanisms, and perspectives

Biochar, Год журнала: 2024, Номер 6(1)

Опубликована: Март 1, 2024

Abstract Soil contamination by uranium presents a burgeoning global environmental concern, exerting detrimental effects on both agricultural production and soil health. Biochar, carbonaceous material derived from biomass pyrolysis, exhibits considerable potential for remediating uranium-contaminated soils. However, comprehensive review of the biochar fate accumulation in soil–plant systems remains conspicuously absent. In this paper, sources are reviewed, impact immobilization detoxification is analyzed. We reviewed status soils globally found that mining activities currently main sources. Further meta-analysis revealed addition significantly reduced bioavailability shoot accumulation, their effect value 58.9% (40.8–76.8%) 39.7% (15.7–63.8%), respectively. Additionally, enhances microenvironment, providing favourable conditions promoting plant growth reducing mobility. focused mechanisms governing interaction between uranium, emphasising roles played surface complexation, reduction, ion exchange, physical adsorption. The modification intensifying these can promote immobilisation Finally, alleviates oxidative stress reduces tissues, thereby mitigating adverse development. Overall, our highlights capacity to remediate through diverse mechanisms, valuable insights sustainable remediation. Highlights Biochar mobility variety including limits its plants. Modified has been shown enhance effectiveness immobilising uranium. application not only promotes remediation but also improves quality. Graphical

Язык: Английский

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Mineral-mediated stability of organic carbon in soil and relevant interaction mechanisms

Eco-Environment & Health, Год журнала: 2024, Номер 3(1), С. 59 - 76

Опубликована: Янв. 3, 2024

Soil, the largest terrestrial carbon reservoir, is central to climate change and relevant feedback environmental health. Minerals are essential components that contribute over 60% of soil storage. However, how interactions between minerals organic shape transformation stability remains poorly understood. Herein, we critically review primary mechanisms, including sorption, redox reaction, co-precipitation, dissolution, polymerization, catalytic reaction. These interactions, highly complex with combination multiple processes, greatly affect through following processes: (1) formation or deconstruction mineral-organic association; (2) oxidative minerals; (3) polymerization (4) varying association according mineral transformation. Several pieces evidence related turnover during interaction in real eco-environment then demonstrated. We also highlight current research gaps outline priorities, which may map future directions for a deeper mechanisms-based understanding storage capacity considering its minerals.

Язык: Английский

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Intrinsic properties of biochar for electron transfer

Chemical Engineering Journal, Год журнала: 2023, Номер 475, С. 146356 - 146356

Опубликована: Окт. 5, 2023

Язык: Английский

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Unrecognized Role of Organic Acid in Natural Attenuation of Pollutants by Mackinawite (FeS): The Significance of Carbon-Center Free Radicals

Environmental Science & Technology, Год журнала: 2023, Номер 57(49), С. 20871 - 20880

Опубликована: Ноя. 29, 2023

Organic acid is prevalent in underground environments and, against the backdrop of biogeochemical cycles on Earth, holds significant importance degradation contaminants by redox-active minerals. While earlier studies role organic generation reactive oxygen species (ROS) primarily concentrated electron shuttle or ligand effects, this study delves into combined impacts decomposition and Mackinawite (FeS) oxidation contaminant transformation under dark aerobic conditions. Using bisphenol A (BPA) as a model, our findings showed that oxalic (OA) notably outperforms other acids enhancing BPA removal, attaining rate constant 0.69 h-1. Mass spectrometry characterizations, coupled with anaerobic treatments, advocate for molecule-O2 activation principal mechanism behind pollutant transformation. Comprehensive results unveiled carbon center radicals, initiated hydroxyl radical (•OH) attack, serve primary agents oxidation, accounting at least 93.6% total •OH generation. This dynamic, driven concurrent formation carbon-centered ensures steady supply electrons ROS The obtained information highlights OA natural attenuation pollutants offers innovative strategies FeS acid-coupled decontamination.

Язык: Английский

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Review on intensified treatment of refractory wastewater in anaerobic digestion based on extracellular electron transfer: Mechanisms, strategies, and applications

Chemical Engineering Journal, Год журнала: 2024, Номер 489, С. 151456 - 151456

Опубликована: Апрель 18, 2024

Язык: Английский

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Heating-Induced Redox Property Dynamics of Peat Soil Dissolved Organic Matter in a Simulated Peat Fire: Electron Exchange Capacity and Molecular Characteristics

Environmental Science & Technology, Год журнала: 2025, Номер unknown

Опубликована: Янв. 2, 2025

Peatlands store one-third of the world's soil organic carbon. Globally increased fires altered peat matter chemistry, yet redox property and molecular dynamics peat-dissolved (PDOM) during remain poorly characterized, limiting our understanding postfire biogeochemical processes. Clarifying these dynamic changes is essential for effective peatland fire management. This study demonstrates temperature-dependent in electron exchange capacity (EEC) PDOM by simulating burning, significantly affecting microbial iron reduction. At low temperatures (200-250 °C), EEC remains constant releasing more phenolic moieties to enhance electron-donating (EDC). Higher (500 °C) diminish 90% consuming phenolic-quinone moieties. Pyrolytic (pyPDOM) contributes 40% soil, with this contribution declining at higher temperatures. Phenolic-quinone primary redox-active pyPDOM. Fourier transform ion cyclotron resonance mass spectrometry analysis shows that EDC depends on types than abundance, monophenol-like molecules (

Язык: Английский

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A comprehensive review on biochar-based materials for the safe utilization and remediation of heavy metal-contaminated agricultural soil and associated mechanisms

Journal of environmental chemical engineering, Год журнала: 2025, Номер unknown, С. 116179 - 116179

Опубликована: Март 1, 2025

Язык: Английский

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Promotion of Humic Acid Transformation by Abiotic and Biotic Fe Redox Cycling in Nontronite

Environmental Science & Technology, Год журнала: 2023, Номер 57(48), С. 19760 - 19771

Опубликована: Ноя. 16, 2023

The redox activity of Fe-bearing minerals is coupled with the transformation organic matter (OM) in dynamic environments, but underlying mechanism remains unclear. In this work, a Fe cycling experiment nontronite (NAu-2), an Fe-rich smectite, was performed via combined abiotic and biotic methods, accompanying humic acid (HA) as representative OM investigated. Chemical reduction subsequent reoxidation NAu-2 produced abundant hydroxyl radicals (thereafter termed ·OH) that effectively transformed chemical molecular composition HA. More importantly, HA served more premium electron donor/carbon source to couple biological Fe(III) reoxidized by Geobacter sulfurreducens, model Fe-reducing bacterium. Destruction aromatic structures formation carboxylates were mechanisms responsible for transforming into energetically bioavailable substrate. Relative unaltered HA, increased extent bioreduction 105%, oxidation even mineralization resulting bleached microbial products cell debris. ·OH slightly decreased shuttling capacity bioreduction. Our results provide mechanistic explanation rapid driven redox-fluctuating environments.

Язык: Английский

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