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

Eco-Environment & Health, Journal Year: 2024, Volume and Issue: 3(1), P. 59 - 76

Published: Jan. 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.

Language: Английский

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Strong Substance Exchange at Paddy Soil-Water Interface Promotes Nonphotochemical Formation of Reactive Oxygen Species in Overlying Water

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(17), P. 7403 - 7414

Published: April 17, 2024

Photochemically generated reactive oxygen species (ROS) are widespread on the earth's surface under sunlight irradiation. However, nonphotochemical ROS generation in water (e.g., paddy overlying water) has been largely neglected. This work elucidated drivers of and its spatial distribution undisturbed water, by combining imaging technology with situ monitoring. It was found that H2O2 concentrations formed three waters could reach 0.03–16.9 μM, profiles exhibited heterogeneity. The O2 planar-optode indicated redox interfaces were not always at soil–water interface but also possibly layer, depending soil properties. facilitated a rapid turnover reducing oxidizing substances, creating an ideal environment for ROS. Additionally, electron-donating capacities increased 4.5–8.4 times compared to top layers. Importantly, field investigation results confirmed sustainable •OH through pathways constituted significant proportion total daily production (>50%), suggesting comparable or even greater role than photochemical generation. In summary, process reported this study greatly enhances understanding natural processes soils.

Language: Английский

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Probing the Photochemical Formation of Hydroxyl Radical from Dissolved Organic Matter: Insights into the H₂O₂-Dependent Pathway

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 17, 2025

This study quantifies the contribution of H2O2-dependent pathway to hydroxyl radical (•OH) production from photolysis dissolved organic matter (DOM). •OH formation rates were cross-validated using benzoate and terephthalate as probe compounds for diverse DOM sources (reference isolates whole waters). Catalase addition revealed that accounts 10-20% total in isolate materials, but no significant correlation was observed between ambient iron (Fe) concentrations formation. lack likely due lower Fe levels isolated thus limiting concentration photochemically produced Fe(II) available reaction with H2O2. Notably, contributed 11 ± 3% Pony Lake fulvic acid, which had lowest content, implicating additional H2O2-driven mechanisms independent Fe. Experiments model acetophenone p-benzoquinone indicated triplet reactions However, rate increased 6-fold when H2O2 reduced by ketyl radicals formed excited 2,4,6-trimethylphenol. advances knowledge photolysis, providing insight into role aquatic photochemical processes.

Language: Английский

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Ozone Micronano-bubble-Enhanced Selective Degradation of Oxytetracycline from Production Wastewater: The Overlooked Singlet Oxygen Oxidation

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 57(47), P. 18550 - 18562

Published: Dec. 7, 2022

The efficient and selective removal of refractory antibiotics from high-strength antibiotic production wastewater is crucial but remains a substantial challenge. In this study, novel ozone micronano-bubble (MNB)-enhanced treatment system was constructed for treatment. Compared with conventional ozone, MNBs exhibit excellent efficiency oxytetracycline (OTC) degradation toxicity decrease. Notably, study identifies the overlooked singlet oxygen (1O2) first time as active species in MNB through probe electron paramagnetic resonance methods. Subsequently, oxidation mechanisms OTC by are systematically investigated. Owing to high reactivity toward 1O2, enhance anti-interference performance raw complex matrixes. This provides insights into mechanism MNB-enhanced pollutant new perspective high-concentration industrial using MNBs. addition, presents promising technology scientific guidance wastewater.

Language: Английский

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Effect of C/Fe Molar Ratio on H₂O₂ and ^•OH Production during Oxygenation of Fe(II)-Humic Acid Coexisting Systems

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(18), P. 13408 - 13418

Published: Sept. 5, 2022

Hydrogen peroxide (H2O2) and hydroxyl radical (•OH) production during oxygenation of reduced iron (Fe(II)) natural organic matter (NOM) in the subsurface has been increasingly discovered, whereas effect C/Fe molar ratio Fe(II) NOM coexisting systems remains poorly understood. In this study, aqueous humic acid (HAred) mixture at different ratios (0-20) were oxygenated. Results show that both H2O2 •OH accumulation increased almost linearly with increase ratio, a more prominent high ratios. At low (C/Fe ≤ 1.6), electrons mainly transferred from dissolved inorganic Fe(II), surface-adsorbed proportion HA-complexed to O2; level ≥ 5), main electron source turned free HAred. The changes transfer pathway yield relative H2O2. This study highlights important role controlling therefore accurately evaluating associated environmental impacts.

Language: Английский

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Microscale Spatiotemporal Variation and Generation Mechanisms of Reactive Oxygen Species in the Rhizosphere of Ryegrass: Coupled Biotic–Abiotic Processes

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(22), P. 16483 - 16493

Published: Nov. 3, 2022

Reactive oxygen species (ROS) play key roles in soil biogeochemical processes, yet the occurrence and accumulation of ROS rhizosphere are poorly documented. Herein, we first developed a ROS-trapping membrane to situ determine ryegrass then quantified temporal spatial variations representative (i.e., O2•─, H2O2, •OH). Fluorescence imaging clearly visualized production rhizosphere. Both O2•─ H2O2 content increased declined throughout life cycle ryegrass, while •OH concentration decreased continuously. Spatially, contents remained at relatively high level 0-5 mm descended with increasing distance. The concentrations different soils followed order black > latosol yellow-brown tier ∼ red soil. Analysis properties suggested that both biotic factors (microbial community) abiotic (Fe(II) water-soluble phenols) played critical production. combined including Fe(II) phenol-mediated electron transfer, microbial community-driven extracellular release, Fe(II)/Fe(III) cycling, may be responsible for These findings provide insights into ROS-associated effects inspiration phytoremediation pollutants element cycling.

Language: Английский

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Dynamic Production of Hydroxyl Radicals during the Flooding–Drainage Process of Paddy Soil: An In Situ Column Study

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(43), P. 16340 - 16347

Published: Oct. 19, 2023

Frequent cycles of flooding and drainage in paddy soils lead to the reductive dissolution iron (Fe) minerals reoxidation Fe(II) species, all while generating a robust consistent output reactive oxygen species (ROS). In this study, we present comprehensive assessment temporal spatial variations Fe ROS during flooding-drainage process representative soil. Our laboratory column experiments showed that decrease dissolved O2 concentration led rapid reduction below water-soil interface, aqueous was transformed into solid phases over an extended time. As result, •OH production capacity liquid reduced improved. The increased from 227-271 μmol kg-1 (within 1-11 cm depth) 500-577 499-902 after 50 day, 3 month, 1 year incubation, respectively. During drainage, dynamic triggered by consumption oxidation. ROS-trapping film situ capture revealed soil surface active zone for intense H2O2 production, limited observed deeper layers (>5 cm) due penetration. These findings provide more insights complex interplay between cycling redox transition zones fields.

Language: Английский

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Hydroxyl radicals in natural waters: Light/dark mechanisms, changes and scavenging effects

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 868, P. 161533 - 161533

Published: Jan. 11, 2023

Language: Английский

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An overlooked influence of reactive oxygen species on ammonia-oxidizing microbial communities in redox-fluctuating aquifers

Water Research, Journal Year: 2023, Volume and Issue: 233, P. 119734 - 119734

Published: Feb. 12, 2023

Language: Английский

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Amendment of organic acids significantly enhanced hydroxyl radical production during oxygenation of paddy soils

Journal of Hazardous Materials, Journal Year: 2023, Volume and Issue: 457, P. 131799 - 131799

Published: June 8, 2023

Language: Английский

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