Molecular Evidence of Arsenic Mobility Linked to Biodegradable Organic Matter

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(12), P. 7280 - 7290

Published: May 14, 2020

Molecular characteristics of natural organic matter (NOM) and their potential connections to arsenic enrichment processes remain poorly understood. Here, we examine dissolved (DOM) in groundwater water-soluble (WSOM) aquifer sediments being depth-matched with samples from a typical arid–semiarid basin (Hetao Basin, China) hosting high groundwater. We used Fourier transform ion cyclotron resonance mass spectrometry determine molecular DOM WSOM evaluate roles biodegradable compounds microbially mediated mobility at the level. High-arsenic was generally enriched recalcitrant molecules (including lignins aromatic structures). Although contribution cannot be ruled out, preferential degradation labile coupled reduction Fe(III) (oxyhydr)oxides seemed dominate mobilization. Both number intensity aliphatic/proteins carbohydrates) were higher than those high-arsenic (arsenic >0.67 μmol/L or 50 μg/L). Groundwater concentration increased increase unique (especially N-containing compounds) matched depths. Anoxic incubations deionized water show that more Fe(II) released greater numbers intensities consumed compounds), proportion derived produced. These observations indicate biodegradation carbohydrates CHON formulas) fueling reductive dissolution predominantly promotes release solids. Our data present better understanding mobilization shaped by microbial anoxic aquifers

Language: Английский

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Carbon Sequestration in the Form of Recalcitrant Dissolved Organic Carbon in a Seaweed (Kelp) Farming Environment

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(12), P. 9112 - 9122

Published: June 10, 2022

Under climate change scenarios, the contribution of macroalgae to carbon sequestration has attracted wide attention. As primary producers, can release substantial amounts dissolved organic (DOC) in seawater. However, little is known about molecular composition and chemical properties DOC derived from which them are recalcitrant (RDOC) that be sequestered for a long time ocean. In most intensive seaweed (kelp) farming area (Sanggou Bay) China, we found kelp mariculture not only significantly increased concentration, but also introduced variety new species, many were sulfur-containing molecules. A long-term degradation experiment revealed those with strong resistance microbial degradation, i.e., RDOC, account approximately 58% extracted area. About 85% (3587 out 4224 different features) RDOC species steadily present throughout process. 15% (637 likely newly generated by microorganisms after metabolizing macroalgae-derived labile DOC. All these stable should included blue budgets seaweed.

Language: Английский

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Composition of dissolved organic matter (DOM) in lakes responds to the trophic state and phytoplankton community succession

Water Research, Journal Year: 2022, Volume and Issue: 224, P. 119073 - 119073

Published: Sept. 10, 2022

Language: Английский

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Eutrophication and watershed characteristics shape changes in dissolved organic matter chemistry along two river-estuarine transects

Water Research, Journal Year: 2022, Volume and Issue: 214, P. 118196 - 118196

Published: Feb. 14, 2022

Language: Английский

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Insight into the characterization of dissolved organic matter in shallow lakes with different trophic states and their net photo-generation capacity of reactive oxygen species

Water Research, Journal Year: 2025, Volume and Issue: unknown, P. 123204 - 123204

Published: Jan. 1, 2025

Language: Английский

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Marine Recalcitrant Dissolved Organic Matter Gained by Processing at Sandy Subterranean Estuaries

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

Published: Feb. 13, 2025

The sandy subterranean estuary (STE) connecting fresh groundwater to saline sea water is characterized by strong geochemical (salinity, redox, and pH) gradients, with evidence emerging for its role as a hot spot consumption of labile substrates. This inspired us conduct study evaluate whether this holds true dissolved organic matter (DOM), especially given the still mysterious origin marine recalcitrant DOM. Here, characterization DOM 21 samples (depth 1-13 m, salinity 3.9‰ 32.4‰) across 65 m transect an STE located in coastal Guangdong, China, has found systematic biotransformation toward "recalcitrant" carboxyl-rich alicyclic molecules (CRAM). fraction CRAM (%CRAM) increases from 33.1% 76.7% increasing degree degradation salinity. Further, processing DOM, including more "biolabile" lower %CRAM released aquitard, active under oxic conditions than reducing conditions. Given large quantities that recirculates through STEs globally, amount (RDOM) entering ocean after likely be considerable. While studies are needed, can gain CRAM-like compounds way.

Language: Английский

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Correspondence between DOM molecules and microbial community in a subtropical coastal estuary on a spatiotemporal scale

Environment International, Journal Year: 2021, Volume and Issue: 154, P. 106558 - 106558

Published: April 23, 2021

Dissolved organic matter (DOM) changes in quantity and quality over time space, especially highly dynamic coastal estuaries. Bacterioplankton usually display seasonal spatial variations abundance composition the regions, influence DOM pool via assimilation, transformation release of molecules. The change can also affect bacterial community. However, little is known on correspondence between molecules composition, particularly through a systematic field survey. In this study, spatiotemporal signatures microbial communities subtropical estuary Xiamen are investigated one half years. co-occurrence analysis bacteria suggested microorganisms likely transformed from relatively high (>400 Da) to low (<400 molecular weight, corresponding an apparent increase overall aromaticity. This might be reason why renders "dark" visible mass spectrometry due more efficient ionization metabolites, as well photodegradation processes. K- r-strategists exhibited different correlations with two-size categories owing their lifestyles responses environmental nutrient conditions. A comparison variables showed that environmental/DOM played important role shaping than vice versa. study sheds light interactions populations at scale, improving our understanding roles marine biogeochemical cycles.

Language: Английский

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Novel Insights into the Molecular-Level Mechanism Linking the Chemical Diversity and Copper Binding Heterogeneity of Biochar-Derived Dissolved Black Carbon and Dissolved Organic Matter

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(17), P. 11624 - 11636

Published: July 1, 2021

Biochar-derived dissolved black carbon (DBC) varies in chemical composition and significantly affects the environmental fate of metal ions. However, intrinsic molecular DBC fractions their interaction mechanisms with ions remain unclear. We propose a novel, molecular-level covariant binding mechanism to comparatively interpret heterogeneities, active sites, sequential responses copper compounds natural organic matter (DOM). Relatively large proportions lipid/aliphatic/peptide-like low mass distributions lignin-like oxidized/unsaturated groups existed acidic- alkaline-extracted DBC, respectively. A larger percentage tannin-like/condensed aromatic higher average conditional stability constants (logK̅Cu) visible fluorescent components were found for DOM than DBC. Overall, 200–320 Da 320–480 contributed logK̅Cu values UVA components, respectively, DBC/DOM. Nitrogenous likely exhibited stronger affinities phenolic/carboxylic groups. The copper-binding DBC/DOM generally followed order → tannin-like condensed compounds. These insights will improve prediction potential effects on various contaminants risks biochar application ecosystems.

Language: Английский

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Hydrological management constraints on the chemistry of dissolved organic matter in the Three Gorges Reservoir

Water Research, Journal Year: 2020, Volume and Issue: 187, P. 116413 - 116413

Published: Sept. 19, 2020

Language: Английский

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Unraveling roles of dissolved organic matter in high arsenic groundwater based on molecular and optical signatures

Journal of Hazardous Materials, Journal Year: 2020, Volume and Issue: 406, P. 124702 - 124702

Published: Nov. 28, 2020

Language: Английский

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