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1. 题目: Chlorine Disinfection Enhances the Degradation of Biodegradable Microplastics into Nanoplastics and Dissolved Organic Carbon in Simulated Disinfection Process
文章编号: N26020912
期刊: Environmental Science: Processes & Impacts
作者: Xuefeng Jiang, Jianxin Fan, Siyu Xu, Bocong Huang, Jiaoxia Sun
更新时间: 2026-02-09
摘要: The extensive global utilization of biodegradable plastics has given rise to the growing presence of biodegradable microplastics (BMPs) in wastewater treatment plants (WWTPs). Although a majority of microplastics can settle in sludge, some still make their way into the disinfection tank. Hence, it is imperative to comprehend the fate of BMPs in the disinfection tank. Polylactic acid (PLA) and polybutylene adipate (PBAT) are the two most prevalently used biodegradable plastics. Consequently, we simulated the disinfection conditions of WWTPs to investigate the aging pathways of granular PLA (PLAg), sheet PLA (PLAs), granular PBAT (PBATg) and sheet PBAT (PBATs) under the influence of the disinfectant sodium hypochlorite (NaClO). Results of scanning electron microscopy (SEM) demonstrated that NaClO notably enhanced the surface roughness of BMPs and triggered the formation of holes and cracks, and this roughness tended to intensify with the elevation of NaClO concentration and the prolongation of aging time. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses revealed that the carbonyl index (CI) and the oxygen-to-carbon ratio (O/C) continuously increased in both PBATg and PBATs throughout the aging process. Nevertheless, PLAg and PLAs presented an initial increase followed by a decrease, which could be attributed to the combined effect of ester bond hydrolysis and NaClO-driven oxidation. Moreover, the concentration of dissolved organic carbon (DOC) increased with both extended aging time and higher NaClO concentration. The detection of biodegradable nanoplastics (BNPs) observed by transmission electron microscopy (TEM) further verified that NaClO aging induced the fragmentation of the parent plastics into BNPs. In summary, our results emphasize that NaClO-driven oxidation results in both physical structural damage and chemical transformation of BMPs. These findings offer a vital theoretical foundation for enhancing wastewater treatment procedures to control BMPs pollution while also providing essential empirical data for future sustainability assessments.

2. 题目: The ocean’s biological carbon pump under pressure
文章编号: N26020911
期刊: Science Advances
作者: Jack J Middelburg
更新时间: 2026-02-09
摘要: Increasing hydrostatic pressure induces the release of dissolved organic matter from rapidly settling marine particles and contributes to the depth attenuation of carbon fluxes.

3. 题目: Hydrostatic pressure induces strong leakage of dissolved organic matter from “marine snow” particles
文章编号: N26020910
期刊: Science Advances
作者: Peter Stief, Jutta Niggemann, Margot Bligh, Hagen Buck-Wiese, Urban Wünsch, Michael Steinke, Jan-Hendrik Hehemann, Ronnie N Glud
更新时间: 2026-02-09
摘要: Marine snow forms at the ocean surface, sinks to depth, and ultimately enables carbon sequestration in the seabed. Fast-sinking marine snow particles, such as diatom aggregates, encounter a rapid increase in hydrostatic pressure during their descent. Using incubations in rotating pressure tanks, we found that pressure levels corresponding to 2- to 6-kilometer water depth induce leakage of dissolved organic matter (DOM) from diatom aggregates equivalent to ~50% of their initial carbon contents. The leaked DOM proved to be diatom-derived and changed the amount and composition of DOM in the surrounding seawater substantially. Ultrahigh-resolution mass spectrometry, high protein-like fluorescence, and low carbon:nitrogen ratios classified the leaked DOM as labile. The bioavailability of leaked DOM was demonstrated by its rapid utilization by a pelagic microbial community, leaving mainly recalcitrant DOM behind. Pressure-induced DOM leakage likely weakens the gravitational “biological carbon pump” and supplies labile DOM to the pelagic microbiome of the deep ocean.

4. 题目: Hydrological Continuums Across Climate and Permafrost Gradients: Spatial Patterns of Organic Carbon, Greenhouse Gases, and Major and Trace Elements
文章编号: N26020909
期刊: Water Research
作者: Ivan V Krickov, Sergey V Loiko, Artem G Lim, Darya M Kuzmina, Georgy I Istigechev, Liudmila S Shirokova, Yuri S Pupyshev, Oleg S Pokrovsky
更新时间: 2026-02-09
摘要: Organic and inorganic solute fluxes from soils to rivers follow a hydrological continuum linking terrestrial and aquatic compartments, yet this cascade remains poorly constrained in permafrost regions despite its importance for carbon and greenhouse gas (GHG) cycling. We investigated six hydrological continuums—soil water, fen, lake, riparian zone, stream, and river—across a 1500 km north–south transect of the Western Siberian Lowland, spanning the full gradient from permafrost-free taiga to continuous permafrost tundra. During summer baseflow, surface and soil waters were analyzed for dissolved organic carbon (DOC), CO₂, CH₄, and 40 major and trace elements. DOC, CO₂, and CH₄ concentrations systematically decreased from soils and fens toward lakes and rivers, highlighting headwaters as dominant sources of carbon and GHGs. Aluminum covaried with DOC, consistent with organic complexation and downstream pH increases, whereas Fe and Mn reflected local redox variability. In contrast, Ca, Mg, Sr, and soluble anions increased downstream in southern, permafrost-free systems, indicating active groundwater inputs, while no such trend was observed in tundra sites under continuous permafrost, pointing to strong hydrological isolation. DOC declined with increasing drainage area, whereas CO₂ and CH₄ showed no consistent dependence on watershed size. Nutrients (Si, P) increased downstream mainly within discontinuous permafrost zones, suggesting enhanced subsurface contributions. Principal component analysis revealed two dominant patterns of covariation: one linking DOC, Fe, Al, and low-mobility lithogenic trace elements, consistent with colloidal transport of organic and organo-ferric complexes, and a second associated with electrical conductivity and labile ions, reflecting variable groundwater influence and subsurface–surface connectivity. GHG concentrations were largely independent of these patterns and instead related to local redox conditions and subsoil CO₂–CH₄ inputs. Overall, this study provides the first integrated, pan-regional assessment of coupled organic carbon, greenhouse gases, and major–trace element dynamics along complete hydrological continuums spanning the full permafrost gradient of the Western Siberian Lowland. By combining multi-compartment sampling with a space-for-time framework, we identify two fundamental controls—colloidal transport limitation and groundwater-driven source limitation—that unify solute behavior across climate zones. The results demonstrate how permafrost extent governs hydrological connectivity, biogeochemical processing, and GHG regimes, offering a mechanistic basis for predicting Arctic river responses to thaw, warming, and changing water–groundwater exchange.

5. 题目: Enhanced polystyrene nanoplastic removal by CTAB-modified magnetic biochar: Adsorption performance and mechanisms
文章编号: N26020908
期刊: Journal of Environmental Management
作者: Longwei Fu, Ruili Gao, Bin Xue, Ran Duan, Kun Ma, Lin Chen, Biao Jia
更新时间: 2026-02-09
摘要: Polystyrene (NPs) nanoplastics are emerging ubiquitous contaminants in aquatic environments, but their efficient removal remains challenging. Although conventional biochar offers cost-effective adsorption potential, its practical application is limited by inherent hydrophilicity and poor retrievability. To address these limitations, we engineered cetyltrimethylammonium bromide-modified magnetic biochar (CTAB/MBC) via chemical co-precipitation, synergistically enhancing both magnetism and CTAB-derived hydrophobicity. Remarkably, CTAB/MBC achieved a maximum NPs adsorption capacity of 234 mg g−1, representing a 2.1-fold increase over unmodified magnetic biochar (MBC) (113 mg g−1). Optimal performance occurred at environmentally relevant pH 7, attributed to its elevated point of zero charge. Coexisting anions (CO32− > SO42−) demonstrated greater inhibition than cations (Ca2+ > Mg2+ > Na+), primarily through competitive electrostatic screening. Integrated characterization (SEM, FTIR, XPS) revealed the primary removal mechanisms involved electrostatic attraction facilitated by cationic quaternary ammonium groups, hydrophobic interactions between CTAB alkyl chains and NPs backbones, and surface complexation with Fe3O4 sites. This work establishes CTAB/MBC as a high-efficiency and magnetically retrievable adsorbent for nanoplastic remediation while providing a sustainable strategy for agricultural biomass valorization.

6. 题目: Straw-induced soil pH decreased drives aluminum speciation shift and enhances soil organic carbon stability: a 12-year paddy experiment
文章编号: N26020907
期刊: Environmental Technology & Innovation
作者: Xingyu Li, Nanyang Wu, Min Mao, Weijia Liu, Dandan Peng, Ouping Deng, Jiang Liu, Xuesong Gao, Bing Li, Changquan Wang, Rong Huang
更新时间: 2026-02-09
摘要: Crop straw application is a critical strategy for enhancing soil organic carbon (SOC) content. However, the impacts of crop straw application on soil acidity and aluminum (Al) fractions have been less explored, and the consequences of these changes for SOC dynamics remain incompletely understood. In this study, a long-term field experiment (12 years) was conducted in a paddy field with continuous crop straw application. A crop straw application treatment [NPK with crop straw (NPK+S)], a conventional mineral fertilization control (NPK), and a non-fertilized control were included. The results show that compared with NPK treatment, the NPK+S treatment can reduce soil pH value by 0.27 units. This is because crop straw promotes the ammonia oxidation process and the increase of cumulative CO2 emissions in paddy field soil. Among them, the number of amoA-AOA gene and cumulative CO2 emissions of NPK+S treatment increased by 82.20% and 27.25% relative to the NPK treatment, respectively. Crop straw application significantly increased the exchangeable aluminum (Ex-Al) and organically bound aluminum (Or-Al) content while markedly decreasing the hydroxide aluminum (Hy-Al) content relative to the NPK treatment. Crop straw application also enhanced the stability of SOC. Specifically, compared with NPK treatment, the humification degree of dissolved organic matter (DOM) and the content of mineral-associated organic carbon (MAOC) in NPK+S treatment increased significantly by 14.80% and 44.29%, respectively, which is related to the transformation of soil Al fractions. Therefore, when utilizing crop straw in paddy paddies, a trade-off between soil acidity and organic carbon sequestration must be carefully considered.

7. 题目: Microplastic-derived dissolved organic matter components determine Microcystis aeruginosa-bacteria interaction network and community assembly
文章编号: N26020906
期刊: Harmful Algae
作者: Zongjie Xie, Huimin Li, Jia Feng, Shulian Xie, Yang Liu
更新时间: 2026-02-09
摘要: Freshwater ecosystems face mounting threats from microplastic pollution, and the dissolved organic matter (DOM) released by these particles represents an emerging ecological risk factor. In this study, a 28-day co-culture experiment was conducted to investigate the comparative effects of photo-aged (UVA-340) MPs-DOM derived from biodegradable poly(butylene adipate-co-terephthalate) (PBAT) versus conventional polyethylene (PE) and polyethylene terephthalate (PET) microplastics on the bacterial community associated with the harmful cyanobacterium Microcystis aeruginosa PCC 7806. Excitation-emission matrix with parallel factor analysis revealed that PBAT-DOM was rich in recalcitrant humic-like components and depleted in labile, protein-like components, whereas PE-DOM and PET-DOM were dominated by protein-like fluorescence. These chemical signatures had strong biological consequences: PBAT-DOM dramatically reduced bacterial diversity and promoted late-stage dominance by Burkholderia–Caballeronia–Paraburkholderia, coupled with a higher inferred contribution of stochastic processes based on null-model and βNTI analyses. In contrast, PE-DOM and PET-DOM maintained higher community evenness and supported temporally variable succession among multiple co-dominant genera (e.g., transient enrichment of Bdellovibrio, Sphingomonas, and Bacteroidota-related genera such as Chryseobacterium/Flavobacterium). Sparse InversE Covariance Estimation for Ecological Association Inference (SPIEC-EASI)–inferred association networks indicated that PBAT-DOM yielded the most modular network with a comparatively lower fraction of positive conditional associations, whereas PE-DOM and PET-DOM maintained well-connected networks with distinct organization patterns. These findings demonstrate that the chemical signature of microplastic-derived DOM critically influences microbial assembly mechanisms. In particular, persistent humic substances from biodegradable plastics may modulate ecological processes by restructuring bacterial communities and carbon cycling, potentially elevating environmental risks in nutrient-sensitive freshwater ecosystems. In summary, microplastic risk assessments should incorporate DOM-mediated effects to better predict long-term impacts on aquatic ecosystems.

8. 题目: Characterization and Stabilization Pathways of Water-Extractable Dissolved Organic Matter in the Mariana Trench Sediments
文章编号: N26020905
期刊: Deep Sea Research Part I: Oceanographic Research Papers
作者: Jiayue Geng, Min Luo, Kexin Zheng, Linying Chen, Tingcang Hu, Dong Zhang, Jingqian Xie, Duofu Chen
更新时间: 2026-02-09
摘要: Hadal trenches have been taken as hotspots for organic carbon burial and microbial activity in the deep-sea settings. In this study, water-extractable (WEOM) and porewater dissolved organic matter (PWOM) were analyzed from two sites in the Mariana Trench—MT04 (clay-dominated) and MT05 (laminated diatom mat, LDM sediments)—to evaluate the influence of mineral association on dissolved organic matter composition, optical characteristics, and stable carbon isotopic signatures. Compared to the LDM core, WEOM in the clay-dominated core shows higher SUVA254, humification index (HIX), and A253/A203 values, but the fluorescence index (FI) is lower. These optical characteristics indicate higher aromaticity, a greater degree of humification and lower bioavailability of WEOM. Such patterns suggest that clay minerals selectively adsorb and occlude aromatic- and carboxyl-rich dissolved organic matter. This mineral association reduces microbial accessibility and enhances long-term preservation. Comparison between WEOM and PWOM further reveals distinct compositional and functional differences within the sedimentary organic carbon pool. WEOM is tightly associated with mineral surfaces, enriched in aromatic and humified components, and exhibits stronger stability, whereas PWOM contains more protein-like and labile constituents. The decreasing trend in δ13C (δ13C of sediment total organic carbon > δ13C of WEOM > δ13C of PWOM) indicates that selective microbial degradation and mineral protection jointly regulate dissolved organic matter transformation pathways. Therefore, WEOM represents a mineral-associated, relatively stable carbon reservoir that plays a crucial role in long-term organic carbon preservation in the deep-sea environment.

9. 题目: Vegetation-Mediated Carbon Inputs and Erosion Protection Shape Soil Carbon Dynamics across Aridity Thresholds
文章编号: N26020904
期刊: Environmental Science & Technology
作者: Yuntao Wu, Josep Peñuelas, Jalaid Naersige, Jie Luo, Heng Ge, Xingming Zhang, Pengfei Chang, Ping Li, Lingli Liu
更新时间: 2026-02-09
摘要: Intensified aridity beyond a critical threshold could disrupt vegetation, microbial, and soil processes, reshaping the mechanisms controlling soil carbon (C) storage in drylands. However, the aridity threshold at which the transition occurs and how the controls over different soil C fractions shift remain unclear. Here, we conducted a 2400 km transect survey across 45 sites spanning a broad aridity gradient in temperate grasslands of China. We identified a pronounced shift in the dominant drivers of soil C storage at an aridity threshold of 0.749. Below this threshold, complex vegetation structures enhanced soil C by promoting microbial activity and mineral abundance, which stimulated the accumulation of both POM and MAOM, with a stronger effect on POM. Above the threshold, fine roots dominated soil biochemical processes, sustaining microbial activity and mineral formation that indirectly stabilized SOC, particularly via MAOM. Across the entire aridity gradient, vegetation structure mediated surface soil susceptibility to wind erosion with complex structures providing effective protection, while simpler structures offered limited buffering. These findings highlight the dual role of vegetation-mediated C input and wind erosion protection in sustaining soil stocks in drylands, underscoring the need to account for canopy and root structure when species are selected for dryland restoration.

10. 题目: Effects of combined humic- microbial amendment on the growth of pakchoi and soil improvement for coal mine subsided area
文章编号: N26020903
期刊: Environmental Research
作者: Huan He, Wenqing Mao, Xitong Heng, Juan Cheng, Mingjun Cao, Qinghe Cao, Zhilin Zhou, Xiuxiang Tao, Gordana Medunić, Zaixing Huang
更新时间: 2026-02-09
摘要: Coal mining-induced subsidence disrupt soil ecosystems and diminishes agricultural productivity, requiring effective remediation strategies. While both lignite derived humic acid and microbial inoculants have individually shown potential to improve soil properties, the combined application of humic-microbial amendment (CHA), remains underexplored, especially with reduced inorganic fertilizer input. This study evaluated the efficacy of CHA in remediating subsidence-affected soil and promoting the growth of Brassica chinensis L. (pakchoi), focusing on soil-plant-microbe interactions. Results (P<0.05) showed that CHA allowed a 50% reduction in inorganic fertilizer usage. The optimal CHA treatment (IFHA) increased soil urease and sucrase activities by 14.84% and 67.46%, respectively, promoted nitrogen and phosphorus uptake in pakchoi, and raised biomass yield by 87.6%. Additionally, protein and soluble sugar contents increased by 22.06–79.94% compared to the control. Microbial analysis revealed that CHA had minimal effect on bacterial abundance but altered the fungal community. Dominant phyla included Ascomycota (with beneficial Penicillium, enhance nitrogen mineralization) and Mortierellomycota (supporting soil nutrient transformation), as well as Streptomyces, a genus involved in carbon cycling. These microbial shifts correlated with improved soil nutrients availability and crop performance, helping mitigated mining-related degradation. Our findings suggest that CHA provides a promising approach for the sustainable remediation of coal mine subsidence soil and offers potential applications for other mining-impacted soils.

11. 题目: Quantifying interactive photochemical and microbial removal of terrestrial dissolved organic carbon: From experiments to modeling
文章编号: N26020902
期刊: Limnology and Oceanography Letters
作者: Patrick Martin, Oon Yee Woo, Yuan Chen, Clement Y Tan, Crystal T Yang, Yongli Zhou, Bernhard Mayer
更新时间: 2026-02-09
摘要: The biogeochemical fate of terrestrial dissolved organic carbon (tDOC) in aquatic environments is a poorly understood part of the carbon cycle. In nature, tDOC undergoes photochemical and microbial degradation simultaneously. However, photochemical and microbial degradation are generally quantified separately, and nonlinear interactions between these processes remain poorly constrained. We describe a novel experimental method to quantify simultaneous photochemical–microbial degradation, and show that interactive photochemical–microbial degradation can account for around half of tDOC and of colored dissolved organic matter degradation. The degradation rates depend asymptotically on the absorbed light dose rate. Our method yields a simple equation that relates the interactive tDOC degradation rate to the absorbed light dose rate, which can be adapted to represent tDOC degradation in biogeochemical ocean models. Our method offers a straightforward and transferable approach to quantify interactive tDOC degradation rates in different ecosystems and to better represent tDOC degradation in biogeochemical ocean models.

12. 题目: Neglected role of extracellular polymeric substances in manganese redox driven nitrogen removal: Inspired from biofilm metabolism
文章编号: N26020812
期刊: Journal of Environmental Chemical Engineering
作者: Zhiqing Ye, Sicheng Shao
更新时间: 2026-02-08
摘要: Manganese-amended moving bed biofilm reactor (MBBR) encounter challenges associated with the interplay between manganese redox and nitrogen conversion. To overcome this limitation, the role of extracellular polymeric substances (EPS) in this interaction is overlooked. This study developed continuous flow MBBR for treating low carbon-to-nitrogen ratio wastewater. The result showed that manganese redox cycling drove simultaneous nitrification and denitrification processes by MBBR with a maximum total nitrogen removal of 85 ± 7 % at hydraulic retention time (HRT) of 10 h, and the stability of manganese redox cycling driven biological denitrification was not related to the magnitude of HRT. The process of nitrogen removal was identified, as well as the components and fluorescence properties of EPS using parallel factor method. Results demonstrated that the proportions of manganese used for nitrogen conversion and manganese redox accounted for 69.3 %±2.7 % and 24.9 %±2.2 %, respectively, and the microbial activity and manganese redox cycling driven nitrogen removal ability were synchronized with EPS yield. The concentration and fate of Mn(II) in three types of EPS were investigated, and the relationship between the main functional groups in EPS/ functional microbial community and nitrogen removal was explored. The result indicated that genus Zoogloea had a strong correlation with NH4+ -N removal, NH4+-N removal displayed a positive correlation with Mn(II) removal. EPS had become a key driving forces for denitrification by mediating the manganese redox cycling, optimizing the biofilm micro-environment, and regulating microbial community. This study extends the understanding of mechanism of manganese redox-mediated nitrogen removal.

13. 题目: Green manure incorporation with 20 % nitrogen reduction enhances soil organic carbon storage by improving aggregate stability and functional group composition
文章编号: N26020811
期刊: Agriculture, Ecosystems & Environment
作者: Pengfei Wang, Aizhong Yu, Keqiang Jiang, Xiaoneng Pang, Jianzhe Huo, Yulong Wang, Yongpan Shang, Shihe Hou
更新时间: 2026-02-08
摘要: Balancing soil carbon sequestration with crop productivity is a pivotal challenge in sustainable agriculture. Leguminous green manure incorporation offers a potential pathway, yet the mechanisms underlying its synergy with reduced nitrogen fertilization in achieving co-benefits for soil carbon sequestration (SCS) and yield stability require further elucidation. A field experiment was conducted from 2023 to 2025 in an oasis irrigated area of Northwest China to evaluate five nitrogen application rates (100 % (N100, traditional nitrogen application), 90 % (N90), 80 % (N80), 70 % (N70), and 60 % (N60)) under leguminous green manure incorporation on maize yield, soil organic carbon storage (SOCs), and the underlying mechanisms. The results indicated that the N80 treatment effectively maintained maize grain yield while significantly enhancing soil organic carbon storage. This synergistic effect was attributed to the improvement of soil aggregate stability and the enhancement of soil organic carbon chemical stability, which was specifically manifested in the N80 treatment exhibiting the highest aromaticity index and the lowest proportion of labile functional groups. Specifically, the N80 treatment increased the proportion of macro-aggregates (>2 mm) and mean weight diameter (MWD), geometric mean diameter (GMD), and the proportion of aggregates > 0.25 mm (DR0.25). Concurrently, scanning electron microscopy observations indicated that the N80 treatment promoted the formation of abundant honeycomb-like pores and ridge-shaped surface structures in the soil. These unique microstructures effectively enhanced the accumulation of organic carbon within aggregates. Fourier transform infrared spectroscopy (FTIR) revealed that the N80 treatment enhanced the aromaticity index (Aromatic C/Aliphatic C) of SOC and reduced the proportion of labile functional groups (specifically, O–H/N–H and C–O groups indicative of polysaccharides and amides). Structural equation modeling confirmed that green manure incorporation with 20 % nitrogen reduction primarily facilitated SOC sequestration by improving aggregate stability and optimizing organic carbon composition. Regression analysis based on a multi-objective comprehensive evaluation model revealed that a nitrogen reduction of 18.74 % is optimal for systems with green manure incorporation. In conclusion, reducing nitrogen application by 20 % combined with leguminous green manure incorporation is an optimal management strategy for synergistically enhancing SOC sequestration, improving soil structure, and securing crop yield in oasis agroecosystems.

14. 题目: Rubber based agroforestry systems enhance soil organic carbon sequestration through changes in soil properties and microbial community structure
文章编号: N26020810
期刊: Applied Soil Ecology
作者: Ashar Tahir, Yingying Zhang, Chuan Yang, Wenxian Xu, Hassam Tahir, Hafiz Muhammad Mazhar Abbas, Zhixiang Wu
更新时间: 2026-02-08
摘要: Rubber monoculture (RM) often causes soil degradation and loss of ecosystem functioning. In contrast, rubber-based agroforestry systems (RAFs) can enhance soil organic carbon (SOC); however, the mechanisms regulating SOC fractions and microbial communities remain poorly understood. This study examined six RAFs comprising Hevea brasiliensis intercropped with Alpinia katsumadai (AKH), Alpinia oxyphylla (AOM), Coffea arabica (CAA), Cinnamomum cassia (CCA), Pandanus amaryllifolius (PAR), and Theobroma cacao (TCA), compared with RM. We quantified SOC fractions (mineral-associated organic carbon, MAOC; particulate-organic carbon, POC), soil properties, enzyme activities, microbial community structure, and microbial co-occurrence networks. After nine years, RAFs significantly increased SOC by 16.3–75.8% (8.96 ± 1.96 g. kg−1) relative to RM, with similar gains in MAOC (18.4–82%), POC (26.5–61.6%), and microbial biomass carbon (MBC; 21.9–47.9%). In the 0–20 cm layer, SOC and MAOC stocks were 18.3–30.8 Mg. ha−1 and 13.7–24.3 Mg. ha−1, respectively, compared with 18.4 and 14.5 Mg. ha−1 in RM. Using RM as the baseline, CAA, CCA, AOM, and AKH accumulated SOC at rates of 1.38, 0.83, 0.59, and 0.43 Mg. C ha−1 yr−1, respectively. RAFs also increased soil pH, reduced bulk density, and enhanced carbon-, nitrogen-, and phosphorus-acquiring enzyme activities. Microbial richness rose in AOM (bacteria, 19.9%) and CCA (fungi, 93.4%). Co-occurrence network analysis showed higher modularity (48%) and fewer antagonistic (2–27%) associations in bacteria, while fungal networks exhibited greater connectivity (18–109%) and clustering (65–190%) than RM. Partial least squares path modeling identified soil properties, MBC, and enzyme activities as significant mediators of SOC fractions. These results suggest that RAFs not only enhance soil fertility and enrich SOC pool but also restructure belowground microbial interactions toward more cooperative networks. Integrating diverse trees, shrubs, and herbs within rubber plantations thus offers a promising strategy to increase ecosystem services, climate resilience, and long-term sustainability in tropical rubber production landscapes.

15. 题目: Effects of oxygen penetration and iron redox shuttling on the preservation of reactive iron-bound organic carbon in a large-river-dominated estuary
文章编号: N26020809
期刊: Geochimica et Cosmochimica Acta
作者: Bin Zhao, Qinsheng Wei, Yi Han, Xiaojing Wang, Yu Zhang, Menglin Yi, Nan Wang, Zongshan Zhao, Baodong Wang, Peng Yao
更新时间: 2026-02-08
摘要: Association with reactive iron (FeR) is critical for the preservation of sedimentary organic carbon (SOC) in marine environments. However, previous studies have focused predominantly on surface sediments, leaving the post-depositional changes in the SOC and FeR association during the early diagenesis poorly understood. In this study, we analyze the characteristics of OC and FeR-bound OC (OC-FeR) in suspended particulate matter (SPM), surface sediments, and box core sediments, as well as the profiles of dissolved oxygen and major ions in the collected sediment cores from the Changjiang estuary. The overarching objective of this study was to investigate the variation in OC-FeR as it transitions from SPM to surface sediments and subsequently to deeper sediment layers under varying redox conditions. High porewater Fe and Mn concentrations, coupled with frequent physical reworking, indicate metal redox shuttling in the mobile-muds zone near the Changjiang estuary, where the reduction of Fe and Mn oxides predominately governs the diagenetic processes. However, the metal reduction process is relatively diminished in hypoxic areas, despite a shallow oxygen penetration depth. The observed higher fraction of OC-FeR in total OC (fOC-FeR) in the mobile muds relative to SPM, alongside a decrease in both OC and FeR content, suggests that OC-FeR is preserved well during sedimentation. Furthermore, the increase in δ13C values of OC-FeR from SPM to surface sediments is mainly attributable to Fe reoxidation at the water–sediment interface, which facilitates the binding of FeR with a portion of marine SOC. However, the shallow oxygen penetration depth in the hypoxic zone restricts Fe reoxidation, resulting in no significant differences in fOC-FeR and δ13C values of OC-FeR between SPM and surface sediments. In deeper sediments, intense Fe reduction diminishes the fOC-FeR in the mobile muds near the Changjiang estuary, indicating that OC-FeR is less effectively preserved. However, no significant variation in fOC-FeR is observed in the deeper sediments of other regions. Considering the impact of Fe reduction on OC-FeR associations during sediment burial, our revised global OC-FeR burial flux (∼44.3 Mt/yr) is lower than previous estimates (∼51.8 Mt/yr), suggesting that only ∼ 14.5% of SOC is associated with FeR globally. This research elucidates the effects of oxygen penetration and iron redox shuttling on the preservation of OC-FeR in large-river-dominated estuaries. These findings have significant implications for refining global coastal carbon budgets, which is essential for accurately predicting and mitigating climate change.

16. 题目: New insights into the molecular interactions of neonicotinoid pesticides to extracellular polymeric substances: Spectroscopy analysis, molecular docking, and DFT simulations
文章编号: N26020808
期刊: Environmental Science: Processes & Impacts
作者: Sipei Yang, Dan Luo, Zhibin Wu, Xiaomin Gong, Pufeng Qin, Yunshan Liang, Yaoyu Zhou
更新时间: 2026-02-08
摘要: The widespread occurence of neonicotinoid insecticides (NEOs) into soil environments inevitably leads to interactions with microbial extracellular polymeric substances (EPS), triggering the formation of complexes that can alter the environmental fate of these pesticides. These interactions are complex and critically influence the behavior of NEOs in soil. However, the underlying binding mechanisms remain poorly understood. Therefore, this study combined multispectral techniques, fluorescence excitation emission matrix-parallel factor analysis (EEM-PARAFAC), two-dimensional correlation spectroscopy (2D-COS), molecular docking (MD), and density functional theory (DFT) simulations to investigate the binding characteristics between bacterial EPS and NEOs (dinotefuran and thiamethoxam). EEM-PARAFAC results showed that EPS were primarily comprised of protein-like substances and humic-like substance. Notably, compared to humic-like substance, protein-like substances in EPS exhibited stronger affinity toward NEOs, with the highest quenching constants of 2.4311 × 10⁸ L/mol for dinotefuran and 4.8663 × 10⁸ L/mol for thiamethoxam. Furthermore, 2D-COS analysis indicated that tyrosine-like substances responded more rapidly to NEOs than tryptophan-like components. Moreover, the MD simulations and DFT simulations indicated that hydrogen bonds and hydrophobic forces were important driving forces for the binding of EPS-NEOs. These findings provide molecular-level insights into the interfacial behavior of NEOs in soil, which is crucial for accurately assessing their environmental fate and ecological risks, and may inform the development of effective remediation strategies for NEOs contaminated environments.​

17. 题目: Enhanced sludge anaerobic digestion by voltage-driven electron transfer of humic acids
文章编号: N26020807
期刊: Journal of Cleaner Production
作者: Yaya Sun, Jun Guo, Fangzhi Jiang, Salma Tabassum, Yudong Pan, Zhun Ma, Hongbo Liu
更新时间: 2026-02-08
摘要: Sludge anaerobic digestion (AD) is often constrained by inefficient extracellular electron transfer (EET), which limits syntrophic metabolism and methane production. Humic acids (HAs), naturally occurring redox-active organic matter, can mediate EET as soluble electron shuttles, but their heterogeneous structures lead to inconsistent activity and even electron competition with microbes. Here, a voltage-driven regulation strategy was developed to enhance the electroactivity of HAs and thereby improve AD performance. Results showed that at the applied voltage of 0.6 V, the electron transfer capacity of HAs increased by 164.0%, transforming them into “super electron shuttles”. Further semi-continuous AD experiments demonstrated that voltage-driven HAs increased methane production by 60.4% and refractory organic removal by 51.5%, while maintaining stability under a high organic loading rate of 10 kg/m3.d. The AD system electrochemical characterization and microbial community analyses revealed that voltage-driven HAs selectively enriched syntrophic VFAs oxidizing and electroactive bacteria, forming a “super electron transfer network” that raised system conductivity by 275.2%. Mechanistic verification via co-culture and electrode insulation experiments proved that applied voltage disrupted HAs’ weak molecular interactions, reduced molecular weight, and exposed quinone-type groups. This structural evolution increased electron storage capacity and accelerated the redox cycling between electrodes and microbes. Collectively, these findings reveal a novel bioelectrochemical pathway for activating the latent electroactivity of HAs, highlighting a promising strategy for efficient waste treatment.

18. 题目: Application of Novel Magnetic Biochar: Material Performance and Mechanisms for Efficient Persulfate Activation in Sulfamethoxazole Degradation
文章编号: N26020806
期刊: Environmental Research
作者: Yunfei Wang, Yuan Wang, Yilin Xie, Xiao Chen, Xiongde Ma, Xueli Wang
更新时间: 2026-02-08
摘要: Biochar (BC) attracts considerable interest owing to its high specific surface area and interconnected porosity. Here, magnetic biochar (CoFe₂O₄@BC) was synthesized via a co-precipitation–calcination route and applied to activate peroxymonosulfate (PMS) for sulfamethoxazole (SMX) abatement. The composite exhibited a markedly increased Brunauer–Emmett–Teller surface area (from 3.6 to 96.7 m² g^-1) and well-dispersed spinel CoFe₂O₄, as confirmed by TEM, SEM, XRD, XPS, and FTIR. Under optimized conditions (CoFe₂O₄:BC = 1:2; [catalyst] = 0.20 g L^-1; [PMS] = 0.20 g L^-1; initial pH = 7), the CoFe₂O₄@BC/PMS system removed >97% SMX within 15 min with an apparent rate constant k_obs ≈ 0.20 min^-1. Radical-quenching tests (MeOH, TBA, p-BQ, L-histidine) and EPR (DMPO/TEMP) indicated the coexistence of radical (SO₄•^-, •OH, O₂•^-) and non-radical (¹O₂) pathways, with ¹O₂ predominating. Coexisting constituents imposed limited interference (Cl^-, NO₃^-, humic acid), whereas HCO₃^- notably suppressed kinetics (kobs down to ∼0.062 min^-1 at high concentration). LC–MS/MS resolved transformation products consistent with S–C/C–N scissions and ring opening, and density functional theory (DFT, Gaussian 16) highlighted susceptible sites on SMX; ECOSAR screening suggested mixed intermediate toxicity that diminished as degradation proceeded. These results identify CoFe₂O₄@BC as an efficient PMS activator for antibiotic abatement in water.

19. 题目: Microbial-mediated structural changes in humic acid increase phosphorus availability in the fertosphere
文章编号: N26020805
期刊: Geoderma
作者: Yanna Luo, Yunbo Niu, Wentao Pan, Lei Shi, Yingqiang Zhang, Xinxin Ye, Qizhong Xiong, Bingqiang Zhao, Jianyuan Jing
更新时间: 2026-02-08
摘要: It is widely accepted that humic acid-enhanced phosphate fertilizers (HAEP) improve crop yield and phosphorus (P) use efficiency, largely because the carboxyl-rich structure of humic acid (HA) reduces P fixation and enhances soil P availability. However, this prevailing view overlooks the potential structural transformations of HA in soil and its localized regulation of P availability—restricted to the phosphate fertilizer fertosphere (PFF) rather than the bulk soil. In this study, we simulated the PFF to examine how HA influences the migration, transformation, and availability of P within the PFF. Using multispectral analysis, we characterized structural changes of HA and its corresponding ability to inhibit P immobilization within the PFF. We also identified the key microbial drivers, thereby clarifying the mechanisms through which HA regulates P availability in this microzone. Compared with that of the control, HA amendment resulted in greater migration of PFF-derived P over 90 days: cumulative migration increased by 10.7%, the migration distance extended by 0.40 mm, and the effective radius of the available P-enriched zones around the fertosphere expanded by 0.84 mm. The increased P availability might be attributed to two main mechanisms. First, the increase in HA-specific surface area and the accumulation of fungal necromass provided additional sites for ion adsorption, thereby inhibiting the transformation of P into insoluble forms. Second, HA slowed the luxury uptake of P by microorganisms, effectively reducing its biological fixation. Notably, the carboxyl functional groups of HA contributed minimally to this improvement. Instead, HA within the PFF underwent progressive depletion of carboxyl groups, mediated jointly by soil bacteria and fungi. HA enhances both the P supply area and the intensity of PFF primarily through microbial-driven structural modifications that maintain its ion-adsorption capacity. These findings offer new perspectives for re-evaluating the efficiency-enhancing mechanisms of HAEP.

20. 题目: Over a decade of minimum tillage: Impacts on soil organic carbon stocks to 70 cm depth in selected East Danish farmer fields
文章编号: N26020804
期刊: Agriculture, Ecosystems & Environment
作者: Henrik Hauggaard-Nielsen, Nikolaj F Z Brandt, Esbern Holmes, Andreas Aagaard Christensen
更新时间: 2026-02-08
摘要: Minimum tillage (MT) practices have gained increasing attention for their potential role in climate change mitigation. However, in temperate regions, studies examining the full soil profile have shown limited or no significant soil organic carbon (SOC) accumulation with MT practices. This study collected soil samples from fields managed by some of Denmark's most experienced MT practitioners and paired them with adjacent conventional tillage (CT) fields. Each MT/CT pair was located within the same geophysical conditions and under similar crop rotations, minimising the risk of confounding variables unrelated to tillage. The results show a strong positive linear correlation (R² = 0.73) between the duration of MT management and the SOC stock difference between paired MT and CT fields across the full 0–70 cm soil depth, suggesting that long-term MT practices may enhance SOC sequestration over time. A more sequential data analysis supported other published works that SOC accumulation in MT fields was primarily confined to the upper 0–10 cm layer, while CT fields exhibited higher SOC stocks in the 10–30 cm layer. No significant differences in SOC were observed below 30 cm. When averaging these numbers across the 0–70 cm profile, SOC stocks did not differ significantly between the tillage systems. Despite limited availability of fields with more than a decade of MT management history farmers' fields serve as valuable, real-world laboratories for understanding the long-term impacts of tillage on SOC dynamics. A scalable pairing methodology is proposed with larger sample sizes in the range of 30–50 paired fields for achieving statistical robustness across heterogeneous agricultural landscapes.