A Critical Review of Groundwater Table Fluctuation: Formation, Effects on Multifields, and Contaminant Behaviors in a Soil and Aquifer System

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(5), P. 2185 - 2203

Published: Jan. 18, 2024

The groundwater table fluctuation (GTF) zone is an important medium for the hydrologic cycle between unsaturated soil and saturated aquifers, which accelerates migration, transformation, redistribution of contaminants further poses a potential environmental risk to humans. In this review, we clarify key processes in generation GTF examine its links with variation hydrodynamic hydrochemistry field, colloid mobilization, contaminant migration transformation. Driven by recharge discharge, regulates water flow movement capillary fringe, control advection dispersion groundwater. addition, formation reactive oxygen species (ROS) waterfall are impacted GTF. changing ROS components partially determine characteristic transformation solutes dynamic microbial population. facilitates (such as nitrogen, heavy metals, non-aqueous phase liquids, volatile organic compounds) through co-migration effect, fields. conclusion, review illustrates limitations current literature on GTF, significance zones underground environment underscored expounding future directions prospects.

Language: Английский

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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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Complementary Elucidation of the Molecular Characteristics of Groundwater Dissolved Organic Matter Using Ultrahigh-Resolution Mass Spectrometry Coupled with Negative- and Positive-Ion Electrospray Ionization

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(11), P. 4690 - 4700

Published: March 11, 2023

The formula assignment of the Fourier transform ion cyclotron resonance mass spectrometry coupled with positive-ion electrospray ionization [ESI(+)-FT-ICR MS] is challenging because extensive occurrence adducts. However, there a paucity automated methods for ESI(+)-FT-ICR MS spectra. novel algorithm spectra developed herein has been applied to elucidate composition dissolved organic matter (DOM) in groundwater during air-induced ferrous [Fe(II)] oxidation. DOM were profoundly impacted by [M + Na]+ adducts and, lesser extent, K]+ Oxygen-poor and N-containing compounds frequently detected when FT-ICR was operated ESI(+) mode, while components higher carbon oxidation states preferentially ionized negative-ion [ESI(−)] mode. Values difference between double-bond equivalents number oxygen atoms from −13 13 are proposed aquatic DOM. Furthermore, first time, Fe(II)-mediated formation highly toxic iodine species reported rich Fe(II), iodide, results this study not only shed light on further development comprehensive characterization ESI(−)-FT-ICR but also highlight importance appropriate treatment specific prior use.

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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Electrokinetic-Enhanced Bioremediation of Trichloroethylene-Contaminated Low-Permeability Soils: Mechanistic Insight from Spatio-Temporal Variations of Indigenous Microbial Community and Biodehalogenation Activity

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(12), P. 5046 - 5055

Published: March 16, 2023

Electrokinetic-enhanced bioremediation (EK-Bio), particularly bioaugmentation with injection of biodehalogenation functional microbes such as Dehalococcoides, has been documented to be effective in treating a low-permeability subsurface matrix contaminated chlorinated ethenes. However, the spatio-temporal variations indigenous microbial community and activity background matrix, fundamental aspect for understanding EK-Bio, remain unclear. To fill this gap, we investigated variation trichloroethylene (TCE) response succession EK-Bio by both column batch experiments. For 195 day (∼1 V/cm, electrolyte circulation, lactate addition), occurred first near cathode (<60 days) then spread anode (>90 days), which was controlled electron acceptor (i.e., Fe(III)) competition microbe succession. Amplicon sequencing metagenome analysis revealed that iron-reducing bacteria (Geobacter, Anaeromyxobacter, Geothrix) were enriched within initial 60 d gradually replaced organohalide-respiring (versatile Geobacter obligate Dehalobacter) afterward. Iron-reducing required an long time consume competitive acceptors so appropriate reductive condition could developed enrichment enhancement TCE activity.

Language: Английский

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Seasonal and Spatial Fluctuations of Reactive Oxygen Species in Riparian Soils and Their Contributions on Organic Carbon Mineralization

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(16), P. 7066 - 7077

Published: April 10, 2024

Reactive oxygen species (ROS) are ubiquitous in the natural environment and play a pivotal role biogeochemical processes. However, spatiotemporal distribution production mechanisms of ROS riparian soil remain unknown. Herein, we performed uninterrupted monitoring to investigate variation at different sites Weihe River zone throughout year. Fluorescence imaging quantitative analysis clearly showed soils. The concentration superoxide (O

Language: Английский

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Critical Role of Mineral Fe(IV) Formation in Low Hydroxyl Radical Yields during Fe(II)-Bearing Clay Mineral Oxygenation

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(22), P. 9669 - 9678

Published: May 21, 2024

In subsurface environments, Fe(II)-bearing clay minerals can serve as crucial electron sources for O2 activation, leading to the sequential production of O2•–, H2O2, and •OH. However, observed •OH yields are notably low, underlying mechanism remains unclear. this study, we investigated oxidants from oxygenation reduced Fe-rich nontronite NAu-2 Fe-poor montmorillonite SWy-3. Our results indicated that dependent on mineral Fe(II) species, with edge-surface exhibiting significantly lower compared those interior Fe(II). Evidence in situ Raman Mössbauer spectra chemical probe experiments substantiated formation structural Fe(IV). Modeling elucidate pathways Fe(IV) respectively consume 85.9–97.0 14.1–3.0% electrons H2O2 decomposition during oxygenation, Fe(II)edge/Fe(II)total ratio varying 10 90%. Consequently, these findings provide novel insights into low different minerals. Since selectively degrade contaminants (e.g., phenol), generation should be taken consideration carefully when assessing natural attenuation redox-fluctuating environments.

Language: Английский

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Electron beam radiation coupled to flocculation for advanced treatment of coking and dyeing wastewater: Performance and synergistic effect

Journal of Cleaner Production, Journal Year: 2024, Volume and Issue: 454, P. 142344 - 142344

Published: April 24, 2024

Language: Английский

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Novel Insights into Sb(III) Oxidation and Immobilization during Ferrous Iron Oxygenation: The Overlooked Roles of Singlet Oxygen and Fe (oxyhydr)oxides Formation

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(26), P. 11470 - 11481

Published: June 12, 2024

Reactive oxygen species (ROS) produced from the oxygenation of reactive Fe(II) significantly affect transformation metalloids such as Sb at anoxic-oxic redox interfaces. However, main ROS involved in Sb(III) oxidation and Fe (oxyhydr)oxides formation during co-oxidation are still poorly understood. Herein, this study comprehensively investigated immobilization process mechanism oxygenation. The results indicated that was oxidized to Sb(V) by aqueous solid phases then immobilized formed via adsorption coprecipitation. In addition, chemical analysis extended X-ray absorption fine structure (EXAFS) characterization demonstrated could be incorporated into lattice isomorphous substitution, which greatly inhibited lepidocrocite (γ-FeOOH) decreased its crystallinity. Notably, goethite (α-FeOOH) favored pH 6 due greater amount Sb(V). Moreover, singlet (

Language: Английский

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