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21. 题目: Soil organic carbon stocks and sequestration rates in Western Australia’s mangroves
文章编号: N26091615
期刊: Geoderma
作者: Enric Gomis, Cristian Salinas, Madison Williams-Hoffman, Nicole E Said, Marta Sánchez Alarcón, Connor Gorham, Axel Werner, Paul S Lavery, Karina Inostroza, Tegan Davies, Pauline F Grierson, Sharyn Hickey, Ben Radford, Enrique Ballesteros, Jeffrey J Kelleway, Pere Masqué, Eduard Serrano, Peter I Macreadie, Catherine E Lovelock, Anna Lafratta, Micheli de Paula Costa, Ruth Reef, Vladimir Levchenko, Fiona Doessel, Matthew A Hayes, Stacey M Trevathan-Tackett, I Noyan Yilmaz, Pawel Waryszak, Rory Crofts, Oscar Serrano
更新时间: 2026-09-16
摘要: Mangroves are widely recognized for their contribution to climate change mitigation. This study provides the first comprehensive assessment of top 1-m and 30-cm soil organic carbon (OC) stocks and accumulation rates across Western Australia’s mangroves, spanning multiple bioregions, geomorphological settings, and intertidal positions. The results revealed (mean ± SE) 236 ± 13 Mg and 83 ± 4 Mg OC ha−1 in top 1-m and 30-cm soils, respectively, accumulated at 443 ± 83 and 215 ± 22 kg OC ha−1 yr−1 over the past 100 and 500 years, respectively. Mangroves across Western Australia exhibited up to 3-fold differences in top 1-m stocks, with highest OC stocks in tropical settings (328 ± 54 Mg OC ha−1) and lowest in temperate mangroves (138 ± 15 Mg OC ha−1). At a landscape scale, mangroves within protected embayments and lower and mid intertidal positions held up to ∼1.5-fold higher OC stocks than those in estuarine settings and upper intertidal positions. Long-term accumulation rates varied up to 6-fold, with highest rates in semiarid bioregions and protected settings. Across 212,000 to 277,000 ha of mangrove extent in Western Australia, total stocks in 1-m soils were estimated at 71–86 Tg OC, accumulated at 94–123 Gg OC per annum. Western Australia’s ongoing mangrove losses have been estimated at 0.27% yr−1, which could result in 177–232 Gg CO2-eq yr−1 emissions. This study estimates the contribution of Western Australia’s mangroves to the global carbon cycle and provides the basis for improving current national carbon inventories and crediting frameworks.

22. 题目: Management legacies and forest attributes shape soil organic carbon dynamics in Quercus ilex open woodlands
文章编号: N26091614
期刊: Forest Ecology and Management
作者: Judit Torres, Isabel Cañellas, Daniel Moreno-Fernández, Isabel González, Gerardo Moreno, Bertrand Guenet, Marta Gómez-Giménez, Benjamín S Gimeno, Inés Santín, Laura Hernández-Mateo
更新时间: 2026-09-16
摘要: Mediterranean open woodlands are increasingly affected by management change and climatic drying, yet the long-term consequences for soil carbon storage and stand condition remain poorly understood. We reconstructed soil organic carbon (SOC) trajectories in Iberian Quercus ilex dehesas by integrating CHELSA climate data, Spanish National Forest Inventory vegetation data, and regional soil observations from a European forest-monitoring network within the RothC model. Simulations covered the upper 20 cm soil layer from 1991 to 2017 and interpreted as model-based reconstructions of relative SOC trajectories. We compared three management trajectories inferred from shrub-cover dynamics: traditional management (TM), land-use abandonment (LA) and shrub clearance (SC). RothC simulations and additive mixed models indicated divergent modelled SOC trajectories associated with contrasting management legacies. LA plots showed the largest net SOC gain (5.12 Mg ha⁻¹) but also the highest tree mortality and shrub encroachment; SC plots showed net SOC losses (-0.43 Mg ha⁻¹) despite improved stand structure; and TM plots showed small net SOC gains (1.93 Mg ha⁻¹). These results suggest a management trade-off: pathways associated with higher modelled SOC accumulation may coincide with structural and demographic degradation that could compromise open-woodland persistence. Within TM plots, mixed‑effects models indicated that adult tree density was positively associated with SOC balance, whereas mortality became negatively associated during the later period; regeneration and shrub cover also showed positive later-period associations. We conclude that adaptive traditional management supporting tree continuity, regeneration, and controlled understory retention may contribute to maintaining both SOC stocks and dehesa functioning under increasing climatic stress.

23. 题目: ZIF-8-engineered Fe/N co-doped biochar enables non-radical peroxydisulfate activation for TPHs degradation in high-salinity oilfield produced water
文章编号: N26091613
期刊: Separation and Purification Technology
作者: Chaomin Jia, Xuhua Cheng, Xuanzhe Xue, Xiaoyu Tang, Nan Yang, Chu Wang, Yao Li
更新时间: 2026-09-16
摘要: High-salinity oilfield produced water (OPW) with refractory total petroleum hydrocarbons (TPHs) remains a global environmental challenge, as conventional advanced oxidation processes are severely suppressed by high-salinity matrices and complex interferents. Herein, a ZIF 8 engineered Fe/N co-doped maize straw derived biochar (Zn/FeN-BC) was rationally fabricated to activate peroxydisulfate (PDS) for TPHs degradation via singlet oxygen (1O2) dominated non radical pathway, enabling exceptional salt tolerance and catalytic stability. The optimized system conducted continuous flow experiments on the actual OPW. Within 1440 mins, more than 85% of TPHs was removed. Mechanistic investigations revealed that ZIF-8 modification tailored the catalyst electronic structure, intensified PDS adsorption, elongated the OO bond, and promoted efficient electron transfer. The Fe-Nx sites and ZIF-8 derived N-doped carbon synergistically drove the selective generation of 1O2, while suppressing radical dominated pathways vulnerable to salt interference. This work elucidates the electronic regulation mechanism underlying nonradical PDS activation, offering a mechanistically grounded, high salt tolerant platform for remediating refractory petroleum contaminated saline wastewater and guiding the design of robust catalysts for complex industrial wastewater.

24. 题目: Microbial mechanisms of biochar-enhanced organic phosphorus mineralization in saline-sodic soils
文章编号: N26091612
期刊: Applied Soil Ecology
作者: Lei Chang, Daping Liu, Tianhang Ju, Yuefen Li
更新时间: 2026-09-16
摘要: Enhancing phosphorus (P) bioavailability is critical for improving saline-sodic soil function, yet the microbial mechanisms governing organic phosphorus (Porg) mineralization under salt-alkali stress remain poorly understood. Using a two-year field experiment with graded biochar application rates, this study systematically elucidates how biochar regulates Porg mineralization through coupled changes in soil physicochemical properties, microbial communities, enzymatic activities, and functional gene expression. Low biochar application (10 t/ha) alleviated salt-alkali stress by reducing soil pH by an average of 10.95%, electrical conductivity by 73.84%, and alkalinity by 45.69%, thereby positively influencing phosphate-solubilizing bacteria and phosphatase activity. This ultimately increased the abundance of genes involved in Porg mineralization by 3.24% on average and P transport by 9.28%. In contrast, high biochar application (60 t/ha) intensified microbial limitations on carbon and phosphorus by 4.47% and 2.81%, inducing increased gene abundance associated with P acquisition and phosphate regulation, which further promoted Porg mineralization. These findings reveal distinct, dose-dependent microbial regulatory pathways underlying biochar-enhanced Porg mineralization in saline-sodic soils and highlight the importance of optimizing biochar application rates to maximize phosphorus bioavailability. This study advances mechanistic understanding of phosphorus cycling during saline-sodic soil restoration and supports biochar-based strategies for sustainable amelioration of alkaline soils.

25. 题目: The vegetation-tidal gradient regulates sediment organic carbon stabilization via microbial transformation and iron-mediated mineral protection in Yangtze Estuary wetlands
文章编号: N26091611
期刊: Environmental Research
作者: Huan Li, Hongjie Zhang, Runhan Yang, Shuwen Xiao, Caitao Wang, Mengting Ji, Dayong Zhao, Jin Zeng
更新时间: 2026-09-16
摘要: Estuarine wetlands are important ‘blue carbon’ sinks, yet their carbon storage exhibits pronounced spatial heterogeneity. The mechanisms by which vegetation distribution and tidal flooding affect sediment organic carbon (SOC) content and stabilization remain unclear. Here, we analyzed the SOC fractions, microbial community composition, and enzyme activities to elucidate the SOC stabilization mechanisms along a vegetation-tidal gradient in the Yangtze Estuary wetlands. Our results showed that the contents of SOC, mineral-associated organic carbon (MAOC), particulate organic carbon (POC), microbial necromass carbon (MNC), iron-associated organic carbon (Fe-OC), microbial biomass carbon (MBC), and enzyme activities decreased from the high-tidal Phragmites australis (HTP) zone to the tidal flat (TF), whereas the relative contributions of Fe-OC and MAOC to SOC rose progressively. Microbial communities shifted from K-strategists to r-strategists and from iron-oxidizing bacteria (FeOB) to iron-reducing bacteria (FeRB) along the gradient. Random forest analysis and partial least squares path modeling revealed that POC accumulation was primarily driven by vegetation-derived inputs and microbial processing, whereas MAOC accumulation was more closely associated with iron-mediated mineral protection. Overall, carbon accumulation in the high-tidal zone is primarily governed by vegetation-derived inputs and microbial transformation, whereas long-term carbon stabilization in low-tidal flats relies more strongly on iron-mediated mineral protection. Increased tidal flooding was associated with greater reliance on mineral-dominated stabilization, yet vegetation preservation remains indispensable for counteracting carbon losses and ensuring sustained sequestration. These findings clarify the spatial patterns and underlying mechanisms of SOC stabilization and provide a scientific basis for blue carbon conservation in estuarine wetland ecosystems.

26. 题目: Identifying transformation of dissolved organic matter in treatment of coal chemical wastewater for zero liquid discharge
文章编号: N26091610
期刊: Water Research
作者: Yang Liu, Yang Luo, Yongxin Wang, Xuedong Zhai, Hui Yan, Jing Ding, Shijie You
更新时间: 2026-09-16
摘要: Accumulation of refractory dissolved organic matter (DOM) poses a critical challenge to stable operation of zero liquid discharge (ZLD) systems in the coal chemical industry. Conventional water quality parameters (e.g., COD and TOC) provide limited insight into DOM compositional complexity, which constrains the targeted selection and optimization of treatment processes. Molecular-level evolution of DOM across the full-scale ZLD system and its implications for process control remain poorly understood. In this study, the fate and transformation of DOM were elucidated in a full-scale ZLD plant treating coal chemical wastewater (CCW). Results revealed that biological treatment shifted DOM toward more saturated and reduced state, accompanied by a substantial decline in oxidized aromatic components, whereas tryptophan-like biogenic metabolites persisted in the treated effluent. Membrane based concentration processes were accompanied by distinct DOM fingerprints in concentrates. High-molecular-weight and sulfur-rich compounds were accumulated in the nanofiltration concentrate (NFC), whereas low-molecular-weight halogenated N-heterocycles were enriched in the ultra-high-pressure reverse osmosis concentrate (UHPROC). UV254 and BIX illustrated exploratory associations with selected aromaticity- and oxidation-related molecular descriptors. This study not only provides mechanistic insights into transformation of DOM in CCW but also suggests engineered strategies for targeted intensification optimization of ZLD system.

27. 题目: Selective transformation of oxidation-derived dissolved organic matter during biofiltration with implications for DBP precursor control
文章编号: N26091609
期刊: Journal of Hazardous Materials
作者: Guojing Shi, Qing-Long Fu, Huang Huang, Shuangshuang Cheng, Junlang Qiu, Zilong Song, Xin Yang
更新时间: 2026-09-16
摘要: Oxidation-biofiltration is widely applied to improve dissolved organic matter (DOM) removal in drinking water treatment, yet the molecular determinants governing the fate of oxidation-derived products remain unclear. This laboratory-scale study investigated the selective fate of oxidation-derived DOM molecules during subsequent biofiltration and identified the molecular characteristics associated with their removal or persistence. Three oxidation processes (O3, O3/H2O2, and O3/UV) were applied to generate compositionally distinct oxidation-derived DOM pools, followed by granular activated carbon and anthracite biofiltration. Oxidation shifted DOM toward more oxygenated and less aromatic compositions, with O3/UV showing stronger depletion of CHO-dominated fractions and less net accumulation of oxidation-derived CHON formulas than O3 and O3/H2O2. During biofiltration, commonly removable formulas were more oxygenated and dominated by CHO than persistent formulas that were enriched in nitrogen and sulfur and had lower O/C ratios. The treatment relevance of these molecular fate patterns was further reflected in disinfection byproduct (DBP) precursor responses: oxidation generally reduced carbonaceous DBP formation potential (C-DBP FP) but increased halonitromethane formation potential (HNM-FP) by 1.7–6.1-fold, whereas subsequent biofiltration reduced both DBP FP and the estimated DBP-associated cytotoxicity index. The pronounced decrease in HNM-FP was consistent with the preferential transformation of more oxygenated N-containing formula-level pools. These findings deepen the molecular-level understanding of oxidation-derived DOM transformation and its selective removal during biofiltration, providing a molecular basis for optimizing DBP precursor control in oxidation-biofiltration processes.

28. 题目: Isopropanol-assisted oxidative reconstruction of commercial polyamide nanofiltration membranes for selective organic matter removal from surface water
文章编号: N26091608
期刊: Separation and Purification Technology
作者: Feilong Zhang, Yixuan Li, Meng Li, Wenxing Yan, Xiaozhen Lu, Daoji Wu, Jun Liu, Qinghao He, Feihong Wang, Xuewu Zhu
更新时间: 2026-09-16
摘要: Commercial polyamide (PA) nanofiltration (NF) membranes are widely used in advanced water treatment, but the properties of their preformed selective layers are difficult to tailor to specific separation requirements. Here, commercial NF270 membranes were reconstructed by isopropanol (IPA)-assisted swelling followed by acidic H2O2 oxidation. HCl treatment induced only minor changes, whereas H2O2 oxidation and IPA swelling promoted PA-network decrosslinking, chain relaxation, and redistribution of surface functional groups. Sequential IPA-H2O2 treatment produced the most pronounced reconstruction, increasing the surface O/N ratio from 1.18 to 1.27 and decreasing the crosslinking degree from 75.3% to 63.5%. The reconstructed selective layer became more negatively charged and hydrophilic and developed larger transport nanochannels, as reflected by a shift in zeta potential from −38 to −63 mV, a decrease in water contact angle from 53.5° to 30.0°, and increases in the molecular weight cutoff and average pore size to 675 Da and 0.66 nm, respectively. Water permeance increased from 15.6 to 25.6 L·m−2·h−1·bar−1, while high sulfate rejection was largely retained. During natural surface-water filtration, the optimized membrane effectively removed humic- and fulvic-like fluorescent dissolved organic matter while allowing partial passage of mineral ions. These results demonstrate the potential of IPA-assisted oxidation to convert commercial PA membranes toward loose-NF behavior for selective surface-water purification.

29. 题目: Efficient capture of U(VI) by Fe-doped biochar derived from agricultural waste
文章编号: N26091607
期刊: Separation and Purification Technology
作者: Jun Liao, Yongqi Zhang, Jiahao Luo, Congcong Ding, Mei Tang, Lielin Wang, Yinhang Zhou
更新时间: 2026-09-16
摘要: The oxidized pig manure biochar doped with reduced iron species (Fe@PBC) was fabricated through facile pyrolysis and in-situ reduction to overcome the drawbacks of conventional carbon-based adsorbents for U(VI) adsorption, including agglomeration, insufficient active sites, weak reducibility and poor anti-interference capacity. An ultra-high adsorption capacity of 623.7 mg/g, fast adsorption equilibrium within 60 min and excellent selectivity toward U(VI) even under interference of coexisting cations were achieved by Fe@PBC. The high removal efficiencies were maintained in tap water and surface water and the stable adsorption performance was retained for at least 6 cycles. Notably, although the coconut shell-derived biochars exhibited significantly higher specific surface areas and more developed mesopores, they showed markedly inferior U(VI) uptake relative to the pig manure-derived counterparts, confirming that surface chemical functionalities, rather than physical pore structures, governed the adsorption process. Besides, the U(VI) immobilization mechanism was attributed to surface complexation by oxygen- and nitrogen-containing functional groups, with the possible participation of iron oxides and iron (oxy)hydroxides in the adsorption process. The column experiments further demonstrated that the breakthrough curves were well described by the Thomas and Yoon-Nelson models, with the breakthrough time being prolonged at lower flow rates, higher adsorbent dosages, and lower influent U(VI) concentrations, confirming the practical applicability of Fe@PBC for continuous wastewater treatment. The low-cost and eco-friendly adsorbent derived from agricultural waste was demonstrated to hold promising potential for efficient remediation of U(VI)-contaminated wastewater.

30. 题目: Humic Acid Promotes Fe(II) Dynamics and Hydroxyl Radical Generation via Interfacial Regulation on Nanoscale Zerovalent Iron for Imidacloprid Degradation
文章编号: N26091606
期刊: Water Research
作者: Du Chen, Jiaming Yi, Zhongyuan Guo, Jian Yang, Wenxuan Ye, Dan Huang, Lin Zhu, Meizhen Wang
更新时间: 2026-09-16
摘要: Interfacial activation of dissolved oxygen by nanoscale zerovalent iron (nFe0) through corrosion-derived Fe(II) offers an effective pathway for oxidative remediation of contaminated water. However, its performance is limited by aggregation, surface passivation, and inefficient Fe(II) utilization, which hinder oxygen activation and oxidative transformation. Herein, humic acid-modified nFe0 (HA-nFe0) was constructed via a Fe(II) pre-coordination strategy for efficient imidacloprid (IMI) removal. Synchrotron-based analyses revealed that HA introduced low-coordination Fe–O structures and redistributed interfacial charges, significantly promoting electron transfer. The optimized HA-nFe0(1/40) achieved 91.5% IMI removal, with a ∼3.5-fold higher reaction rate constant than pristine nFe0. Crucially, the enhanced reactivity was governed not simply by increased Fe(II) production, but by the HA-regulated speciation and dynamic evolution of interfacial Fe(II). Through Fe coordination and electron shuttling, HA regulated the dynamic redistribution of strongly bound, weakly adsorbed, and dissolved Fe(II), thereby sustaining reactive interfacial Fe(II) and promoting the sequential conversion of oxygen intermediates to sustain ·OH generation. DFT calculations further showed that HA lowered *OH adsorption energy for rapid radical release, facilitating ·OH release and sustained oxidative reactivity. Continuous-flow experiments confirmed excellent stability over 28 days with reduced ecotoxicity of transformation products. This work establishes a mechanistic link between HA-regulated interfacial Fe(II) dynamics and oxygen activation, providing an interfacial perspective for regulating the oxidative reactivity of Fe-based environmental materials via natural organic matter.

31. 题目: Unraveling the mechanism of persistent lake eutrophication: Organic phosphorus molecular composition mediates internal phosphorus feedback
文章编号: N26091605
期刊: Water Research
作者: Mi Wang, Yi Wang, Chunlei Song, Xiuyun Cao, Guanglong Liu
更新时间: 2026-09-16
摘要: Sediment organic phosphorus (OP) is a key internal source sustaining lake eutrophication after external P reduction, yet its molecular-level response to trophic gradients and regulatory mechanisms remain unclear. In this study, we characterized OP fractions, bioavailability, and molecular composition in sediments from 11 lakes across trophic states in China using chemical extraction, enzymatic hydrolysis, and Fourier transform ion cyclotron resonance mass spectrometry. The results showed that sediment OP content was positively correlated with trophic states. Bioavailable OP, including labile OP (LOP) and moderately labile OP (MLOP), accounting for 28.8%-76.5% of sediment OP. With increasing trophic level, LOP and MLOP contents increased significantly; LOP hydrolysis shifted from labile monoester P to diester P dominance, whereas MLOP remained labile monoester P dominated. The P‑containing molecules showed higher molecular weight, enhanced aromaticity, lower oxidation state, and greater labile molecules abundance with increasing trophic states. Relative abundances of lipid‑, protein‑, and lignin‑like compounds of P‑containing molecules were positively correlated with trophic level, indicating algal production and external inputs synergistically drove sediment OP accumulation. Partial least squares path modeling showed that OP bioavailability had a negative direct effect on trophic level, but a positive indirect effect via molecular composition, suggesting molecular composition may act as a important mediator converting potentially available OP into long‑term ecological effects. Our findings indicate that enrichment of labile molecules (lipids and proteins) in sediment OP enhances bioavailability, exacerbates eutrophication and promotes algal sedimentation, forming a self‑reinforcing positive feedback. This study reveals the molecular mechanisms by which sediment OP drives persistent eutrophication, providing a basis for internal P risk assessment and targeted eutrophication control.

32. 题目: Contrasting mechanisms of soil carbon sequestration in upland soils: Fungal-driven physical protection with straw versus bacterial-driven mineral stabilization with biochar
文章编号: N26091604
期刊: Journal of Environmental Management
作者: Caidi Yang, Yang Liu, Yu Zheng, Keying Qi, Fazhu Zhao, Jun Wang
更新时间: 2026-09-16
摘要: Understanding the distinct mechanisms by which straw and biochar regulate soil organic carbon (SOC) sequestration is essential for optimizing agricultural practices. To investigate the physical-microbial coupling mechanisms of SOC sequestration, we amended three upland soils collected from Yuzhong (YZ), Yangling (YL), and Changwu (CW) of the Loess Plateau with 13C-labeled straw and biochar. Straw promoted the formation and carbon (C) enrichment of macroaggregates (>0.25 mm), increasing macroaggregate-associated SOC by 40–110% in YZ and YL soils. Conversely, biochar increased the proportion of silt-clay fractions (<0.053 mm) and elevated SOC therein, with a 257% increase observed in CW soil. Straw stimulated certain r-strategist bacteria such as Proteobacteria and Bacteroidota, whereas biochar favored K-strategists such as Actinobacteriota, leading to more complex bacterial co-occurrence networks and greater niche differentiation. Path modeling and correlation analyses revealed two distinct sequestration pathways: a fungal-driven physical protection pathway under straw, wherein fungi promoted macroaggregate formation that physically protected particulate organic C (POC); and a bacterial-driven mineral stabilization pathway under biochar, wherein its chemical stability and porous structure enhanced organic matter adsorption and bacterial activity, promoting the formation of stable mineral-associated organic C (MOC). Specifically, straw was better suited for coarse-textured or low-SOC soils with unsaturated aggregate formation, whereas biochar was more effective in fine-textured or high-SOC soils with abundant mineral surfaces for MOC stabilization. Matching amendment type to soil conditions could therefore maximize C sequestration potential in dryland farming systems.

33. 题目: Interactions between Photochemical and Microbial Degradation on the Pyrogenic Soil-Derived Dissolved Organic Matter
文章编号: N26091603
期刊: Environmental Science & Technology
作者: Yingran Song, Biwei Yang, Gege Yin, Guoping Chen, Chen He, Quan Shi, Guangcai Zhong, Chunling Luo, Gan Zhang, Junjian Wang
更新时间: 2026-09-16
摘要: Photochemical and microbial processes act as primary pathways regulating the transformation and fate of pyrogenic dissolved organic matter (pyDOM) in natural environments, yet their interactions remain poorly understood under different heating conditions. Here, we combined optical spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry to elucidate how photochemical and microbial degradation (applied individually, concurrently, or sequentially) altered pyDOM carbon loss and molecular composition. Microbial degradation caused 38–67% dissolved organic carbon (DOC) reduction and preferentially removed labile aliphatic and peptide-like compounds, whereas photochemical degradation yielded smaller DOC losses (28–62%) but extensive molecular diversification (20–68% newly formed formulas). Concurrent degradation led to intermediate DOC loss but the highest molecular diversity, likely due to transient microbial suppression by reactive oxygen species. Sequential degradation revealed strong process-order dependence. Photochemical pretreatment enhanced subsequent microbial degradation, particularly for high-temperature pyDOM enriched in aromatic molecules (up to 20% extra DOC degradation), while microbial pretreatment produced microbially processed residues that were only slightly further photodegraded. Despite distinct pathways, both sequences converged toward similar optical and molecular signatures, indicating a persistent pyDOM fraction dominated by photochemical transformation products. These findings reveal that not only the fire conditions but also the temporal coupling of photochemical and microbial reactions. not only the fire conditions but also the temporal coupling of photochemical and microbial reactions; refers to two independent factors that jointly regulate the degradation efficiency, compositional trajectory, and persistence of pyDOM..

34. 题目: Unraveling the Importance of Carboxyl Groups in Photochemically Excited Triplet Formation of Chromophoric Dissolved Organic Matter
文章编号: N26091602
期刊: Environmental Science & Technology
作者: Huajing Zhou, Hongyan Ren, Lingxiang Zhao, Yu Lei, Xin Lei, Jiarui Han, Bo Pan
更新时间: 2026-09-16
摘要: Carboxylation and decarboxylation are among the most ubiquitous processes in chromophoric dissolved organic matter (CDOM) transformation, occurring during humification, photooxidation, and microbial activity. However, their impacts on the formation of excited triplet-state CDOM (3CDOM*) remain poorly constrained. Using more than 20 model compounds representing common CDOM chromophores, we demonstrate that carboxylation enhances triplet quantum yields (Φ) by 1.1–69-fold relative to their parent compounds. Consistently, Φ values of CDOM isolates positively correlate with their carboxyl content. Theoretical calculations reveal that carboxylation shifts the lowest excited state from locally excited π–π* character toward mixed n−π*/charge-transfer states and increases spin–orbit coupling, thereby promoting intersystem crossing and triplet formation. Building on these insights, we developed quantitative models that predict Φ using thermodynamic and electronic descriptors and established empirical relationships between Φ and bulk CDOM properties, including molecular weight and total antioxidant capacity. Furthermore, solar irradiation of humic acid induced decarboxylation accompanied by a decline in Φ, whereas carboxyl introduction enhanced the overall photochemical reactivity of CDOM toward organic contaminant degradation. Together, these findings elucidate how carboxylation–decarboxylation modulates 3CDOM* formation, advancing mechanistic understanding of aquatic reactive species generation and natural attenuation of organic contaminants.

35. 题目: Disturbance-Driven Reactive Oxygen Species Generation Promotes Organic Carbon Mineralization in Sediments of Lake Taihu
文章编号: N26091601
期刊: Environmental Science & Technology
作者: Wenkang Li, Na Song, Huacheng Xu, Siwen Li, Kunliang Jiang, Wei Yao
更新时间: 2026-09-16
摘要: Lake sediments are prone to disturbance from anthropogenic and natural processes, inducing O2 intrusion that can generate reactive oxygen species (ROS). However, the occurrence and accumulation of ROS production in O2-perturbed lake sediments are poorly documented. Herein, we investigated ROS production in oxygenated sediments from the sediment-water interface to a depth of 41 cm at 14 different sites in Lake Taihu, China. Results showed that ROS exhibited distinct depth-dependent variations, such that the concentrations of H2O2 and •OH increased with increasing depth, while those of O2•– peaked in 11–16 cm range. Autoclaving sterilization experiments revealed that the proportion of biotic ROS declined while those of abiotic ROS increased with increasing depth, with specific contribution determined by sediment characteristics. Surface-disturbed sediments contained rich and active microbial communities, with biotic processes contributing significantly to ROS production. Abiotic process became the dominant contributor in deep-disturbed sediments due to more reduced components. Random forest and partial least-squares path model analyses further demonstrated that physicochemical properties and bacteria community were primary drivers for ROS production in sediments. Moreover, the generated •OH significantly promoted the abiotic mineralization of sediment organic carbon, accounting for 7.0–32.4% of CO2 efflux. Our research expanded ROS distribution and demonstrated mechanisms for ROS production in lake sediments, which can contribute to a deeper understanding of the carbon cycle as well as pollutant attenuation in lake ecosystems.

36. 题目: Applying a combination of artificial humic acid and microbial agent to increase rhizosphere soil organic carbon content and maize yield
文章编号: N26091514
期刊: Plant and Soil
作者: Yue Yuan, Wentao Li, Qingyu Liu, Xi Zhang, Fan Yang, Zhuqing Liu, Kui Cheng
更新时间: 2026-09-15
摘要: Background and Aims Biostimulants, including artificial humic acid (A-HA) and microbial inoculants, are gaining attention for enhancing soil fertility and crop growth. This study explores their combined effects on rhizosphere soil organic carbon (SOC) fractions and microbial activity. Methods In this investigation a pot experiment of maize was carried out with six treatments, including the synergistic or independent action of artificial humic acid and microbial agents, and a control. Then soil at various growth stages were collected to determine organic carbon, enzyme activity, microorganism community structure, and the growth of the maize, which has been calculated and analysed by high throughput sequencing, principal component analysis and Shannon index to evaluate the effects of different treatments. Results A-HA at 200 mg/kg enhances the availability of nutrients, enzyme activity, root development and favors superior growth, better yielding capacity and increasing stability of soil carbon with microbial agents. It increases soil humification, decreases the activity of enzymes for carbon turnover at 400 mg/kg, decreases gene abundance for metabolism of nutrients, increases gene abundance for carbon fixing microbes and gene abundance of stable pathway of carbon so as to increase the active organic carbon to stable organic carbon and elevate the content of overall soil organic matter. Conclusion The combined application of A-HA and microbial inoculants significantly enhanced SOC fractions and soil nutrient conditions, while stabilizing microbial community abundance in the rhizosphere. This study provides theoretical guidance for improving crop yield through practical application of these soil amendments.

37. 题目: Waste-derived hierarchical biochar with lignosulfonate/melamine-induced mesopore formation and S-assisted N retention for sustained nutrient delivery
文章编号: N26091513
期刊: Bioresource Technology
作者: Yuyang Cong, Dongni Qiu, Jie Li, Honghao Chen, Zhenlin Huang, Yuchen Pan, Donghai Wang, Ke Zhang, Mingfeng Wang
更新时间: 2026-09-15
摘要: The sustainable valorization of waste biomass into high-value functional materials via advanced thermochemical processes is a critical frontier for environmental nutrient management. Herein, a novel spatial-infilling and interfacial reconstruction strategy was proposed to engineer a rice husk biochar carrier via the synergistic vacuum impregnation and co-pyrolysis of lignin sulfonate and melamine. This process induced mesopore formation, pore-structure reconstruction, and pore-size redistribution, shifting the average pore width from 28.41 to 2.71 nm while increasing the surface area from 5.42 to 120.70 m2/g. Meanwhile, sulfur-assisted nitrogen retention promoted the enrichment of Lewis-basic pyridinic-N and polarizable thiophenic-S sites. Adsorption investigations demonstrated a highly efficient, spontaneous, and exothermic multilayer urea capture capacity (Qm = 236.49 mg/g; ΔH° = −16.97 kJ/mol), driven by internal pore-filling and strong interfacial hydrogen bonding/dipole interactions. Crucially, the 2.71 nm nanoconfinement effect restricted urea crystallization, trapping the guest molecules in an amorphous state that established a robust kinetic barrier against dissolution. Multi-model release kinetics confirmed the profound suppression of the initial burst release, with the first-cycle rapid release fraction plummeting from 87.89 % (pure urea) to 13.79 %. The composite displayed a highly stable, slow-phase diffusion-governed sigmoidal profile (λ = 4.80). Pearson correlation verified that the release longevity was controlled by a dual-effect synergistic mechanism combining physical confinement within tortuous channels with robust chemical anchoring by polar functional groups, rendering this engineered biochar a highly promising nutrient delivery platform for sustainable agriculture.

38. 题目: Natural humification-inspired bioenzymatic catalysis drives hydroponic root-zone decontamination and carbon sequestration
文章编号: N26091512
期刊: Journal of Hazardous Materials
作者: Ziyan Niu, Qian Yin, Chunxia Liu, Mengke Song, Shunyao Li, Jialin Yu, Zhao Ma, Kai Sun
更新时间: 2026-09-15
摘要: Endocrine disruptors bioaccumulate along food chains, impairing reproductive function in wildlife and elevating chronic disease risk in humans. Natural humification-inspired bioenzymatic catalysis (NH-IBC) can interrupt pollutant transfer from crops to higher trophic levels, but its efficacy in hydroponic root-zone decontamination and carbon sequestration remains poorly characterized. Here, we demonstrated that NH-IBC enhanced the polymerization and humification of dissolved organic carbon in the hydroponic root-zones of ryegrass (Lolium perenne L.), resulting in a 17.3-fold increase in the dissipation kinetic constant of bisphenol A (BPA, a model endocrine disruptor) relative to the bioenzyme-deficient control. Mechanistically, NH-IBC generated reactive radical intermediates that boosted the copolymerization of root exudates (phenolic acids, amino acids) with BPA, forming water-insoluble, high-molar-mass polymers through stable covalent cross-coupling. This efficient polymerization, coupled with carbon sequestration, reduced BPA phytotoxicity and promoted ryegrass root cell proliferation and elongation. Mass balance and 14C-ring-labeled BPA analyses confirmed that NH-IBC diminished BPA uptake and subcellular distribution in ryegrass. Hydrophobic BPA oligomers and polymers accumulated primarily in root epidermal and cortical tissues, limiting translocation to the endodermis and edible aerial parts. Our findings present a natural humification-inspired biocatalytic framework to remediate contaminant pollution and sequester carbon, advancing agroecosystem sustainability and improving crop- and animal-derived food safety.

39. 题目: Bonded Water Is an Integral Component of Dissolved Organic Matter in the Ocean
文章编号: N26091511
期刊: Geophysical Research Letters
作者: Kaijun Lu, Xiao You, Laodong Guo, Carlos Baiz, Zhanfei Liu
更新时间: 2026-09-15
摘要: Dissolved organic matter (DOM) in the ocean, as one of the largest pools of reduced carbon on Earth, plays an important role in the global carbon cycle, yet its chemical structure remains largely unknown. Here we show that high molecular weight DOM (HMW‐DOM) contains approximately 10% bonded water (H 2 O) by weight. These bonded H 2 O molecules are an integral part of the DOM organic complex, likely maintained through strong intermolecular hydrogen bonds, as they are not released during freeze drying and show minimal exchange with surrounding water. When the bonded H 2 O was removed by mild heating (70°C), the HMW‐DOM became more bioavailable as shown by laboratory incubation experiments. These findings suggest that the bonded H 2 O plays a key role in regulating the stability and biogeochemical cycling of DOM in the ocean.

40. 题目: Hydroclimatic seasonality, bacterioplankton, and dissolved organic matter in a semi-enclosed plateau lake
文章编号: N26091510
期刊: Journal of Hydrology
作者: Wei Zheng, Fan Xia, Qian Bao, Yalan Zhu, Muzi Li, Xiaoyan Tang
更新时间: 2026-09-15
摘要: Dissolved organic matter (DOM) is a central component of carbon cycling, yet the associations among hydroclimatic conditions, bacterioplankton communities, and DOM composition remain insufficiently understood in plateau lakes. This study investigated the seasonal variation of chromophoric dissolved organic matter (CDOM) and its associations with bacterioplankton communities in Qionghai Lake, a semi-enclosed plateau lake in southwestern China. Across the four sampling campaigns, CDOM exhibited a strong autochthonous and microbial signature, with protein-like components accounting for 53.2% of the total fluorescence. CDOM abundance peaked in autumn, when aCDOM(355) reached 1.94 ± 0.24 m−1, coinciding with elevated concentrations of TN and NH4+-N and a higher contribution from the microbial humic-like component C1. In contrast, winter exhibited the lowest aCDOM(355) (0.85 ± 0.23 m−1), the highest Ca2+ concentrations, and the lowest contribution from the tryptophan-like component C4. Bacterioplankton communities also showed clear seasonal shifts, and network analysis identified different bacterial assemblages associated with humic-like and protein-like CDOM fractions. At the annual scale, partial least squares path modeling revealed contrasting microbial patterns: nutrient conditions were positively related to α-diversity, which was inversely related to microbial CDOM, whereas physicochemical conditions were more strongly related to β-diversity, which covaried positively with terrestrial CDOM. Overall, seasonal hydroclimatic variation was accompanied by shifts in CDOM abundance, composition, and bacterioplankton community structure, providing new insights into seasonal carbon cycling and bacterioplankton–DOM linkages in plateau lakes.