Insight into Redox Sites and Intermolecular Interactions of Soil Dissolved Organic Matter through Diverse-Compost Applications Using VSOMM2 and Schrödinger

ACS ES&T Engineering, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 31, 2024

Substituting chemical fertilizers with compost is anticipated to facilitate the disposal of organic waste and mitigate nonpoint source pollution. However, research investigating impact diverse-compost utilization on reactivity soil at molecular-level remains lacking. Herein, quantification identification molecular-scale redox sites intermolecular interactions dissolved matter (DOM) using diverse composts during a crop rotation cycle were investigated unified theoretical modeling approach VSOMM2 Schrödinger. Results showed that use considerably altered molecular weight composition DOM. In particular, we successfully optimized validity coefficient unit model's number construct 38 models DOM molecules identify quantify distribution within molecules. Moreover, distinct roles different in modulating determined cycle. The application cow manure increased quinone, Ar–COOH, Ar–SH contents Model(EAC+), while food enhanced Ar–OH Ar–NH2 Model(EDC+). Finally, rotatable bonds, cation−π interactions, aromatic H-bonds, π-stacking, salt bridges identified electron transfer DOM, which can be further via use. findings this study provide insights into environmental biochemical reactions involving microcatalysts, metal reduction fate, pollution soil, providing basis for enhancing instead fertilizers.

Language: Английский

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Reduction of hexavalent chromium by compost-derived dissolved organic matter

Environmental Science Processes & Impacts, Journal Year: 2024, Volume and Issue: 26(12), P. 2297 - 2308

Published: Jan. 1, 2024

Compost-derived dissolved organic matter (DOMC) is a heterogeneous assemblage of different redox-active molecules. We hypothesize that DOMC can interact with Cr(VI) and reduce it to Cr(III), thereby influencing the dynamics in soil aquatic environments. Here, DOMC, along humic substances isolated from red black soil, were fractionated into acid fractions (i.e., HAC, HAB, HAR) fulvic FAC, FAB, FAR), respectively. The reduction interaction between six investigated. results showed total capacity (TRC) was 26.77-49.34 μM per mg OM. TRC HA 35.54-49.34 OM, which exceeded FA (26.77-31.29 OM). had HA/FA ratio 0.64, higher than substance (0.59) (0.20). sum 35.57 larger (32.87 OM) (33.01 positively correlated TOC, TN, phenol C, alkyl aromatic C contents negatively E2/E3, O-alkyl carboxyl contents. at pH 6 negligible, whereas 32-67% reduced 2. capacities (RC2, RC2, RC6) 2-6 (R2 > 0.71) C. Spectral analysis there no obvious complexation 6, thus but solution could affect accessibility molecules influence reduction.

Language: Английский

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Insights on the Abiotic/Biotic Interactive Impacts on the Occurrence of PFASs in Municipal Solid Waste Landfill Leachate

Water, Journal Year: 2024, Volume and Issue: 16(23), P. 3436 - 3436

Published: Nov. 29, 2024

Per- and polyfluoroalkyl substances (PFASs) presented in landfill leachate can be transported to groundwater soil, posing risks human health food water. However, the occurrence characteristics of PFASs influence paths abiotic biotic factors have not been fully discussed. Our study found that detection rate samples was 100%; ΣPFASs ranged from 1328 ng/L 37,447 ng/L; average 9593 ng/L. Most physical chemical indexes showed a significant positive correlation with concentration, main including TOC, sodium ion, chromium chloride ion. Moreover, dissolved organic matter had very important on environmental behavior PFASs. The degree (DOM) humification promoted transportation PFBA PFBS waste leachate, while microbial DOM inhibited ∑13 PFCAs. microorganisms were mainly Firmicutes, Campylobacterota Proteobacteria, among which there negative between indicating highly toxic Proteobacteria would inhibit growth leachate. Firmicutes little Synergistota, Halanaerobiaeota, low abundance, both positively correlated various This result may imply these rare microphyla are driving transformation Microorganisms indirectly affected PFASs, by influencing Therefore, affecting In summary, pollution management landfills should enhanced regulating control

Language: Английский

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