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1. 题目: Differential fouling behaviors of standard and monovalent-selective membranes by digestate-derived dissolved organic matter in selectrodialysis
文章编号: N26051515
期刊: Water Research
作者: Xiaofang Pan, Jingwei Xu, Yenan Li, Yahui Huang, Victor Nikonenko, Natalia Pismenskaya, Zhi-Long Ye
更新时间: 2026-05-15
摘要: The selective recovery of nutrients from anaerobic digestate via selectrodialysis (SED) is hampered by dissolved organic matter (DOM) which induced membrane fouling. This study systematically investigates the impact of real digestate DOM on the performance of standard (SA, SC) and monovalent-selective (MVA, MVC) ion-exchange membranes during SED. Results indicated that DOM presence increased energy consumption by 10-15% and notably reduced the current efficiency of anions. Fluorescence excitation-emission matrix analysis revealed that humic acid-like and soluble microbial by-product-like substances were the primary foulants. Anion-exchange membranes, particularly SA, were most susceptible to fouling, evidenced by significant surface morphological changes and increased hydrophobicity. DOM fouling was found to promote water splitting at the membrane surface, leading to substantial pH fluctuations in the process streams, which further influenced DOM speciation and transport. Interestingly, monovalent-selective membranes, especially MVA, exhibited superior antifouling properties compared to their standard counterparts. Furthermore, biofouling was identified as a key factor contributing to the selective loss of ammonium nitrogen. This study provides critical insights into the multifaceted mechanisms of DOM fouling in SED and underscores the importance of membrane selection and process control for the efficient nutrient recovery from organic-rich waste streams.

2. 题目: Fluvial connectivity drives carbon cycle dynamics in a tropical mega‐delta
文章编号: N26051514
期刊: Limnology and Oceanography
作者: Adrian M Bass, Wenguang Tang, Andrew C G Henderson, Virginia N Panizzo, James Fielding, Abhra Chanda, Souvik Shil, Tuhin Ghosh, Charlotte Slaymark, Andy Large
更新时间: 2026-05-15
摘要: Coastal estuaries are hotspots of biogeochemical cycling, biodiversity, and sediment processing, yet the drivers of carbon cycle processes remain poorly constrained. Here, we elucidate the influence of hydrological connectivity on carbon biogeochemistry in the Indian Sundarban over successive monsoon seasons by comparing hydrologically connected channels with perennial freshwater flow to channels isolated from feeding rivers. Results demonstrate dissolved organic carbon (DOC) and particulate organic carbon (POC) varied significantly with both season and connectivity. Dissolved organic carbon peaked pre‐monsoon and POC during the monsoon, with higher concentrations in hydrologically connected sites. Dissolved inorganic carbon (DIC) declined during the monsoon season but showed no connectivity effect. Elevated DOC relative to conservative mixing was attributed to freshwater runoff or groundwater input. Isotope data (δ 13 C) indicated POC respiration dominated during pre‐ and post‐monsoon, while DOC flocculation during the monsoon controlled POC dynamics, particularly in connected sites. Carbonate dissolution primarily regulated pre‐monsoon DIC, while organic matter degradation dominated in the monsoon and post‐monsoon periods. CO 2 efflux, measured across all sites, was consistently a source to the atmosphere and two to four times higher in connected channels, with higher turbulence driving maximum fluxes. Our findings demonstrate that hydrological connectivity fundamentally structures estuarine carbon cycling, lowering organic carbon concentrations and enhancing CO 2 fluxes. Shifts in global coastal delta sediment dynamics, in association with anthropogenic river management, therefore, have the potential to significantly alter delta carbon dynamics on a global scale.

3. 题目: Soil Respiration in a Karst Old‐Growth Forest Responds Inconsistently to Driving Factors Across Different Seasons
文章编号: N26051513
期刊: European Journal of Soil Science
作者: Jie He, Yujiao Qi
更新时间: 2026-05-15
摘要: Soil respiration (Rs) is a critical component of the carbon cycle in forest ecosystems and is governed by a complex interplay of biotic and abiotic factors. However, the seasonal variations in how Rs respond to these factors remain unclear, particularly in ecologically sensitive karst old‐growth forests. On the basis of these findings, we conducted seasonal measurements of Rs alongside a comprehensive suite of above‐ and belowground variables in a representative subtropical karst evergreen and deciduous broad‐leaved mixed forest and used a structural equation model (SEM) to investigate the dominant drivers of spatiotemporal variation in Rs across different seasons and to elucidate their potential interrelationships. The results indicate that the seasonal variations in Rs are largely determined by soil temperature. Soil temperature ( β —path coefficient in SEM = 0.71), litter organic carbon ( β = 0.06), soil organic carbon ( β = 0.11), soil available phosphorus ( β = −0.08), and slope position ( β = −0.13) directly affect Rs. Additionally, soil temperature variation also constitutes a significant pathway influencing Rs by affecting changes in soil organic carbon and soil available phosphorus contents. Spatially, moderate to strong spatial autocorrelation of Rs was detected across all four seasons. The spatial autocorrelation ranges for spring, summer, autumn, and winter are 15.3, 17.7, 65.3 and 26.4 m, respectively. In spring, soil temperature ( β = 0.35) was the most significant driver of spatial heterogeneity in Rs. During summer, soil factors explained the majority of the spatial heterogeneity in Rs. The autumn Rs was significantly influenced by stand density ( β = −0.20) and slope position ( β = −0.31), whereas the variation in the winter Rs was primarily regulated by litter factors. These findings highlight the critical role of different factors in modulating both the magnitude and spatial heterogeneity of Rs, thereby enhancing our understanding of how forest soil carbon emissions fluctuate with climate change and providing new insights into understand and assess terrestrial ecosystem C cycling.

4. 题目: Microbe-mediated changes of soil dissolved organic matter in the rhizosphere of Pinus massoniana during vegetation restoration in a typical red soil erosion region of southern China
文章编号: N26051512
期刊: Plant and Soil
作者: Chuifan Zhou, Yilin Fan, Shuzhen Wang, Yanlin Zhang, Weijuan Qiu, Yuanchun Yu, Lei Chen
更新时间: 2026-05-15
摘要: Background Vegetation restoration enhances soil carbon sequestration, yet the mechanisms linking soil organic matter accumulation to rhizosphere microbial dynamics remain unclear. Methods This study examined rhizosphere DOM and microbial communities of Pinus massoniana across a restoration chronosequence in Changting County, a typical red soil-eroded region in southeastern China. Using FT-ICR-MS (Fourier transform ion cyclotron resonance mass spectrometry) and high-throughput sequencing, we characterized root-associated DOM composition and rhizosphere microbial diversity. Results Results showed that vegetation restoration was associated with increased DOM molecular diversity and Shannon index, alongside rising O/C ratios, NOSC (average nominal oxidation state of carbon), AImod (modified aromaticity index), and CHO indices, and declining H/C ratios and MLBL percentage. The abundance of lignin/CRAM-like (lignin/carboxyl-rich alicyclic-like) and tannin compounds increased, accompanied by a shift toward larger DOM molecules (mass-to-charge ratio (m/z) > 450) and a reduction in smaller ones (m/z < 300). Rhizosphere bacterial and fungal alpha diversity increased across the chronosequence, with the abundance of oligotrophic taxa (Alphaproteobacteria, Acidobacteria, Solibacteres) also increasing and potentially contributing to nutrient cycling and recalcitrant SOM decomposition in the plant rhizosphere. PICRUSt2 (phylogenetic investigation of communities by reconstruction of unobserved states) suggested a functional shift from inorganic phosphate transport in early stages to phosphate solubilization and mineralization in later stages. Correlations between DOM properties and microbial assembly were consistent with substrate preference and life-history strategies influencing rhizosphere DOM stability. Conclusion This study reveals an association between vegetation restoration and a successional shift from labile to recalcitrant rhizosphere DOM states, patterns consistent with root-associated microbial restructuring toward oligotrophy. These findings improve understanding of rhizosphere biogeochemical cycling under vegetation restoration, providing a basis for understanding root-mediated carbon persistence mechanisms in degraded red soils.

5. 题目: Riverbed sediment controls organic carbon mineralization pathways in Rivers of revegetated watersheds on the loess plateau
文章编号: N26051511
期刊: Catena
作者: Zechao Gao, Peng Shi, Yalong Han, Lulu Bai, Zhanbin Li, Peng Li
更新时间: 2026-05-15
摘要: The water-sediment interface acts as a core reactor for the riverine carbon cycle, releasing substantial CO2 into the atmosphere through the microbial mineralization of dissolved organic carbon (DOC). However, the role of riverbed sediment in regulating organic carbon mineralization and its quantitative mechanisms remain unclear, particularly in ecosystems undergoing large-scale vegetation restoration. This study investigated rivers within a revegetated small watershed on the Loess Plateau. Using laboratory dark incubation experiments at constant temperature, combined with analyses of microbial communities and functional genes, we elucidated the seasonal mechanisms governing the sediment's contribution to organic carbon mineralization. Results indicated that riverbed sediment served as a continuous carbon source for the overlying water; after a 42-day incubation, particulate organic carbon (POC) content was at 0.598–0.824 times its initial value. The sediment significantly enhanced total CO2 emission primarily by alleviating nitrogen limitation in the water column and altering DOC composition. The contribution of sediment to organic carbon mineralization potential (CS) peaked during the wet season (52.020 ± 8.054%), coinciding with the lowest cumulative mineralization, and reached a minimum during the dry season (43.417 ± 6.688%), when cumulative mineralization was highest. A high CS state was characterized by a low abundance of carbon degradation (e.g., xylA, sga) and carbon fixation (e.g., rbcL) genes in the initial water column, and was significantly positively correlated with sediment fungi capable of decomposing recalcitrant organic matter (e.g., Amniculicola, Castanediella). These findings provide a theoretical reference for understanding the drivers of microbial spatiotemporal patterns in riverine carbon cycling and offer a scientific basis for comprehensively assessing the ecological benefits of vegetation restoration on the Loess Plateau.

6. 题目: Co-variation among DOM components, Fe fractions, and Cd / As mobility under fulvic acid amendment in flooded paddy soils.
文章编号: N26051510
期刊: Ecotoxicology and Environmental Safety
作者: Bo Li, Jibiao Geng, Qihong Zhu, Yanan Wang, Shiming Su, Daoyou Huang, Xibai Zeng
更新时间: 2026-05-15
摘要: Both dissolved organic matter (DOM) and Fe oxides are key factors associated with cadmium and arsenic (Cd / As) behavior in paddy soils. However, the co-variation of DOM and Fe fractions induced by humic acid-like substances and their effects on Cd / As availability are not fully evaluated under flooded conditions. Hence, a 60-day incubation experiment was conducted to elucidate the effects of fulvic acid on Cd / As behavior under reduction conditions using a Cd / As co-contaminated paddy soil. Results showed that FA addition resulted in a significant decrease in CaCl2-Cd (14.1-28.5%) and an increase in KH2PO4-As (9.5-28.1%). These were accompanied by a redistribution of Cd from the exchangeable fraction (EX-Cd) toward more stable forms (CA-Cd, WOM-Cd, and OX-Cd), and by a reduction in Fe-As together with increases in AE-As and Al-As fractions. Total DOM content increased markedly upon FA addition, with substantial increases in humic-like (C1 and C2, 0.9-1.5-fold) and protein-like (C3, 1.3-3.7-fold) components. Furthermore, decreases in Fed (6.2-11.5%) and increases in Feo (6.2-25.9%) under reduction conditions were accelerated by FA amendment. Random Forest (RF) and Structural Equation Modeling (SEM) analysis consistently identified DOM components and Fe fractions as the dominant predictors of Cd / As availability. The relationships among DOM components, Fe oxide fractions, and metal availability suggest that the co-variation of DOM components and Fe fraction changes may contribute to reduced Cd availability. In contrast, the increased As mobility may be associated with Fe oxide reduction, DOM competitive interaction, and possible As valence transformation. These findings provide association-based evidence linking DOM composition, Fe fraction changes, and Cd / As behavior in flooded paddy soil.

7. 题目: Coupled controls of river stage dynamics and vegetation evapotranspiration on the retention of dissolved organic carbon in the riparian zone
文章编号: N26051509
期刊: Journal of Hydrology
作者: Zhibo Zhang, Shaolin Yang, Chaomeng Dai, Zhi Li
更新时间: 2026-05-15
摘要: Riparian zones serve as crucial transitional zones linking terrestrial and aquatic ecosystems. Their intense hydrological exchange processes render them significant hotspots for biogeochemical cycling. However, the combined influence of hydraulic forcing induced by river stage fluctuations and ecological regulation driven by vegetation evapotranspiration on the migration of externally sourced dissolved organic carbon (DOC) remains insufficiently understood. This study developed a coupled numerical model simulating the movement of soil water and solute transport under variable saturation conditions. A vertical two-dimensional simulation domain was established based on China’s Jianghan Plain. Multiple numerical scenarios were designed with different river stage amplitudes ranging from 0 to 1.5 m and leaf area index scaling coefficients () ranging from 0 to 1.5. The model systematically analysed the interactive effects governing riparian DOC exchange fluxes, their spatiotemporal distribution, and enrichment processes. The results showed that river stage fluctuations acted as the primary physical driver controlling the strength of external solute inputs. In contrast, vegetation cover primarily reshaped internal solute distribution by altering the hydrodynamic field. The hydraulic pump effect generated by vegetation transpiration, coupled with in situ evaporation and concentration processes, jointly drove the active accumulation of solutes from deep pore water towards the root zone. The temporal analysis revealed a pronounced counterclockwise hysteresis in the response of DOC transport to hydraulic gradients. This pattern indicated that vegetation evapotranspiration effectively retained high solute concentrations during the recession phase of river stage fluctuations. Moreover, the fitted results from the Generalized Additive Model (GAM) indicate that a nonlinear threshold in soil hydraulic properties constrains the enhancing effect of vegetation on solute enrichment. At low cover levels, increased vegetation significantly boosts enrichment efficiency. However, when leaf area index (LAI) exceeds the threshold of 4.5, the partial effect actually shows a declining trend. In summary, this study clarifies the physical mechanisms of solute transport in riparian zones, explaining its shift from hydraulic-driven input to vegetation-controlled retention. These findings provide a scientific basis for managing riparian carbon sinks through optimized vegetation and hydrologic regulation.

8. 题目: Seasonal variability in trace metal deposition and total organic carbon fluxes on a productive South Atlantic western continental margin.
文章编号: N26051508
期刊: Science of the Total Environment
作者: Alina Criane de Oliveira Pires, André Luiz Belém, Ana Luiza Espadano Albuquerque, Vinicius Tavares Kütter
更新时间: 2026-05-15
摘要: Metals and metalloids play fundamental roles in ocean biogeochemical cycling, modulating processes in the carbon cycle. In the South Atlantic, there are still significant gaps in knowledge about the distribution and biogeochemical dynamics of these elements, particularly in offshore regions of the Brazilian continental margin. This study investigated the fluxes of these elements on the continental margin of Cabo Frio (RJ), using sediment traps for 263 days (24 samples). Total mass fluxes showed a wide range of variation. Metal fluxes also varied considerably among the analyzed elements. Among them, V exhibited the highest variability, whereas Mn showed the most stable behavior, with the narrowest range. TOC fluxes similarly displayed noticeable variability over the study period from 4.5 × 10-5 to 6.4 × 10-3 mg/m2/day. Multivariate analyses revealed the organization of the elements into groups with distinct geochemical behaviors: lithogenic elements associated with terrigenous transport (Al, Ti, and As), elements related to biogeochemical and nutritional processes (Ni, Zn, and Cr), and manganese exhibiting redox control. During periods of upwelling, TOC exhibited decoupled behavior with respect to metals, indicating distinct sources and deposition mechanisms for organic matter and inorganic elements. The results indicated wide variability in mass fluxes and the analyzed elements, reflecting the strong influence of specific hydrodynamic processes, such as upwelling and downwelling.

9. 题目: Valorising cinnamon crop residue: Hydrochar production for sustainable agriculture and carbon emission mitigation.
文章编号: N26051507
期刊: Journal of Environmental Management
作者: R A Don Rasanja Asela Ranasinghe, Gajasinghe Arachchige Ganga Kavindi, Wenjun Liu, Ge Gao, K H G M Tharanga, Tian Yuan, Motoo Utsumi, Zhongfang Lei
更新时间: 2026-05-15
摘要: Thermal conversion of crop residue into soil amendment is a negative emission technology used in circular agriculture. However, limited research has explored the large amounts of crop residues, like wood, scrape, and leaves generated during cinnamon production in Sri Lanka for hydrochar production and its agri-environmental implications. This study used cinnamon leaf waste to produce hydrochar at 190, 220, and 260 °C for 30 and 60 min, and compared it with the raw material and its biochar counterpart produced at 550 °C for 30 min. Both char materials eliminated the phytotoxicity and reduced the electrical conductivity of cinnamon leaves, promoting seed germination. The hydrochar yield reduced with temperature and marginally increased with reaction duration (67% at 190 °C for 60 min and 49% at 260 °C for 30 min), whereas biochar yield remained below 30%. The hydrochar has a lower pH (5.1 - 6.3) than biochar (pH ∼ 7.8) and retained more nitrogen (>1.6%) than biochar (0.8%). According to the carbon persistence quantified by H/C ratios, hydrochar produced at 260 °C for 60 min had a shorter mean residence time (111 years) and a greater carbon storage capacity (442 kg CO2eq/ha) than biochar (over 600 years and 437 kg CO2eq/ha), owing to its higher yield and organic carbon content. Producing hydrochar at 260 °C for 60 min presented the best results for carbon sequestration and agricultural application of biomass, suggesting a promising approach for valorising cinnamon leaf waste for sustainable agriculture.

10. 题目: Physicochemical properties of agricultural biochar for the removal of perfluoroalkyl substances (PFAS) from aqueous solutions.
文章编号: N26051506
期刊: Journal of Environmental Management
作者: Kalidas Mainali, Brajendra K Sharma, Charles A Mullen, Majher I Sarker, Wei Zheng, Candice Ellison, Rafael A Garcia
更新时间: 2026-05-15
摘要: Per- and polyfluoroalkyl substances (PFAS) are increasingly prevalent in aquatic ecosystems worldwide, with their concentration continuing to rise. Carbon-rich sorbents have attracted growing attention as promising materials for removing PFAS from contaminated water. In agricultural settings, PFAS present in irrigation water pose emerging risks to crops and may ultimately enter the human food supply. This study provides a systematic comparison of 12 pristine and activated biochars for PFAS removal using controlled laboratory batch experiments. The physicochemical properties of these biochars were comprehensively characterized using thermal analysis (TGA, DTG), elemental analysis, FTIR, BET surface area measurements, SEM-EDX imaging, and Zeta potential measurements. The activated biochars exhibited high specific surface areas (817-1372 m2/g) and substantial pore volumes. Notably, the fully activated biochars produced from switchgrass, willow, and soy straw achieved 98.0-99.5% removal of long-chain PFAS through adsorption. Enhanced PFAS removal was associated with materials possessing high surface area and optimized pore structures, which increase both the number and accessibility of active sites. Hydrophobic interactions between PFAS's fluorinated chains and nonpolar surfaces, together with hydrogen bonding and pore-filling, were identified as the dominant removal mechanisms. Overall, tailoring the physicochemical properties of biochar is a promising and sustainable strategy for the effective removal of long-chain PFAS from aqueous systems.

11. 题目: Tannic acid: an underexplored fraction of natural organic matter in ultrafiltration membrane processes.
文章编号: N26051505
期刊: Journal of Environmental Management
作者: Bongyeon Jung, Sungju Im, Chang Min Park, Min Jang, Yeomin Yoon
更新时间: 2026-05-15
摘要: Ultrafiltration (UF) membranes are effective for removing natural organic matter (NOM), a known precursor of carcinogenic disinfection byproducts. Most previous studies have used humic acid (HA) as a representative NOM in UF processes, whereas research on tannic acid (TA), a naturally occurring polyphenolic compound, remains limited. In this study, the performance (i.e., water flux and NOM removal) of UF membranes treating TA-containing water was evaluated and compared with that of UF membranes treating HA-containing water. Under different pH conditions, both HA and TA showed the highest removal efficiencies at pH 3 (80-84% for both HA and TA), followed by pH 7 (71-78% for HA and 46-79% for TA), and then pH 10 (62-69% for HA and 18-38% for TA). However, TA removal dropped significantly at pH 10 owing to the hydrolysis of TA molecules, whereas the decrease in HA removal was relatively minor. Under all the tested conditions, TA consistently caused a greater flux decline than HA, and TA fouling was more irreversible. Substantial reduction in the pore size of the TA-fouled membranes was observed, indicating severe fouling. This pronounced fouling was also observed when TA was added to the HA solutions and natural river water. Overall, our results highlighted that the presence of TA in UF processes can lead to more severe fouling than HA, a commonly used NOM surrogate. These findings suggest that greater attention should be paid to the presence of TA in feed water during water treatment processes.

12. 题目: Stage-Dependent Counteracting Effects of Biochar on Arsenic Mobilization and Immobilization in Paddy Soil
文章编号: N26051504
期刊: Journal of Hazardous Materials
作者: Jianxin Fan, Maoyu Liao, Ting Duan, Tingting Fan, Jiaoxia Sun, Bocong Huang
更新时间: 2026-05-15
摘要: Biochar amendment has been widely reported to influence arsenic (As) mobility in flooded paddy soils. While previous studies have mainly attributed biochar-induced As behavior to feedstock, pyrolysis temperature and modification methods, how As dynamics evolve across different incubation stages remains poorly understood. In this study, four types of biochar were applied to flooded soil columns to investigate their effects on As risk. Results showed a potential stage-dependent counteracting effect: biochar may promote As mobilization during the first two weeks, while subsequently facilitated As immobilization (days 14–30), and subsequently re-mobilized As (days 30–90). In the early stage, biochar induced an alkaline, reducing, and DOC-enriched environment, which may have contributed to As mobilization in association with As(V) and Fe(III) reduction. Conversely, after two weeks, high-molecular-weight DOC (humic substances) was likely associated with As immobilization through complexation with Fe. Biochar addition enhanced nitrate- and sulfate-reducing microbial functions, which may have contributed to As mobilization through the dissolution of Fe (hydro)oxides. Although this enhancement was more pronounced during the early incubation stage, microbial processes may have remained important after day 30. Furthermore, biochar samples with higher ash content, pH, and H/C ratios showed stronger associations with both initial mobilization and subsequent immobilization. In contrast, biochar samples with higher BIX and FI indices showed stronger associations with microbial community variation, and correspondingly exhibited the greatest re-increase in aqueous As concentrations after day 30. This study highlights the importance of temporal dynamics in biochar application in flooded As-contaminated soil.

13. 题目: Electron‑Flow‑Driven Synergistic Mineralization of Naphthalene by an S‑N‑Doped Biochar‑Bridged engineered Consortium
文章编号: N26051503
期刊: Journal of Hazardous Materials
作者: Fuliang Bai, Chao Yang, Ze Yu, Zeya Wu, MingXia Sun
更新时间: 2026-05-15
摘要: Microbial synergy in naphthalene biodegradation is frequently constrained by the inefficiency of diffusion-based metabolite transfer. To address this limitation, we assembled immobilized engineered microbial systems (imGEMs) by co-anchoring engineered Pseudomonas stutzeri (overexpressing nahAc and nahB) and Rhodococcus rhodococcus (overexpressing nahH and catA) on S-N-doped biochar (S-N-BC). In this engineered consortium, Pseudomonas stutzeri acts as an oxidative bio‑anode that initiates naphthalene degradation and releases electrons. The S‑N‑BC matrix functions as an electron‑conductive interface, facilitating direct interspecies electron transfer (DIET) and enhancing extracellular electron transfer (EET). This directed electron flux is harnessed by Rhodococcus rhodococcus, serving as a reductive bio‑cathode, to drive its oxygenolytic ring‑cleavage catalysis. The resulting bioelectrochemical synergy achieved exceptional naphthalene removal (>98.3%) and mineralization efficiency (89.5%) by circumventing diffusive bottlenecks and minimizing intermediate accumulation. Electrochemical and multi‑omics analyses confirmed the establishment of this syntrophic circuit, demonstrating elevated electron flux, coordinated upregulation of catabolic genes, and reorganization of electroactive membrane components. Moreover, the immobilized system exhibited outstanding operational stability, maintaining high degradation efficiency over 30 days under varying environmental conditions. In conclusion, this work establishes a robust electron‑flow‑driven paradigm that integrates metabolic engineering with conductive material design for the efficient and sustainable bioremediation of persistent aromatic pollutants.

14. 题目: Optimizing Nitrogen Fertilization through Combined Sources and Split Humic Acid Application Improves Wheat Productivity and Stress Resilience in Semi-arid Soils
文章编号: N26051502
期刊: Water, Air, & Soil Pollution
作者: Tahir Fazal, Muhammad Aurangzaib, Umar Arshad, Rashid Iqbal, Muhammad Raheel, Allah Ditta, Mohamed Taha Yassin
更新时间: 2026-05-15
摘要: Globally, increasing wheat productivity remains a major challenge, particularly in regions where soil fertility is declining and climate change impacts are increasing. Low soil organic matter limits nutrient availability, reduces nitrogen (N) use efficiency, and increases N losses, ultimately affecting crop performance. This field study evaluated individual and combined nitrogen fertilizer sources with single and split humic acid applications at wheat key growth stages (tillering and booting). The combined application of nitrogen sources (urea, CAN, AS) with split humic acid (HA) significantly enhanced physiological, morphological, and biochemical attributes compared with unfertilized control. Photosynthetic parameters improved markedly, including chlorophyll a (56.08%), chlorophyll b (85.36%), total chlorophyll (54.92%), membrane stability index (44.07%), stomatal conductance (43.01%), internal CO₂ concentration (46.91%), transpiration rate (51.42%), and photosynthetic rate (51.84%). Growth and yield traits were substantially enhanced, with increases in plant height (37.5%), tillers m−2 (90.1%), grain yield (94.06%), and biomass yield (107.09%). Antioxidant enzyme activities (SOD, POD, CAT, APX) also increased significantly, suggesting improved oxidative stress regulation under elevated temperature conditions. Among N sources, the combined N treatment performed best, while split HA application proved superior to single application. Notably, although urea is prone to higher losses in semi-arid conditions, it exhibited greater effectiveness than CAN and AS when combined with split HA. The findings demonstrate that integrated nutrient management using diversified N sources and split HA application enhances nitrogen fertilizer productivity, physiological performance, antioxidant activity and wheat yield under semi-arid condition.

15. 题目: Designing biochars for improved sorptive removal of per‐ and polyfluoroalkyl substances
文章编号: N26051501
期刊: Journal of Environmental Quality
作者: Wei Zheng, Erin Huggett, Sophie Circenis, Kalidas Mainali, Brajendra Sharma
更新时间: 2026-05-15
摘要: The widespread occurrence of per‐ and polyfluoroalkyl substances (PFAS) in aquatic environments, along with their adverse impacts on human health, has been recognized as an emerging issue. Sorption using carbon‐based sorbents is the most common approach for PFAS removal. However, conventional biochars typically underperform compared to activated carbon, which is effective but relatively costly. In this study, a designer biochar was developed by using lime sludge, a no‐cost byproduct from drinking water treatment plants, as a pretreatment for woody biomass followed by systematic optimization of lime‐sludge loading, pyrolysis temperature, and residence time. The results showed that the pretreatment process enhanced pore development and modified the surface chemistry of the designer biochar. Under optimal conditions (1:4 lime sludge‐to‐biomass, 850°C, 5 h), the designer biochar achieved near‐quantitative removal (>99%) of perfluorooctanoic acid and both linear and branched perfluorooctane sulfonate, outperforming unmodified biochar and comparable to a commercial activated carbon. Sorption kinetics and isothermal studies confirmed the superior performance of the designer biochar, exhibiting rapid equilibration (<1 h) and increased sorption capacity. Mechanistic analysis revealed that improved PFAS removal by the designer biochar was driven by multiple adsorption mechanisms, including hydrophobic interactions, electrostatic attraction, and cation bridging facilitated by Ca 2 + and Mg 2 + species derived from lime sludge. This study highlights lime sludge pretreatment as a sustainable and cost‐effective strategy for producing high‐performance carbon‐based sorbents for PFAS remediation in contaminated water systems.

16. 题目: Volcanism-driven anomalous organic matter enrichment in saline lacustrine basins: insights from the Permian Lucaogou Formation, NW China
文章编号: N26051421
期刊: Organic Geochemistry
作者: Yingxing Gan, Hongjing Zhao, Yongbin Quan, Jie Wang, Xiongfei Xu, Liwen Yang, Xiaohong Lei
更新时间: 2026-05-14
摘要: The mechanism linking volcanism to anomalous organic matter enrichment in saline lacustrine basins remains unclear. Here, the second member of the Middle Permian Lucaogou Formation (P2l2) in the Malang Sag, Santanghu Basin, is examined using TOC, Rock-Eval parameters, biomarker proxies, mineral compositions, and major- and trace-element data. The P2l2 is divided into a non-volcanic activity stage (NVAS) and a stable volcanic activity stage (SVAS) based on tuff occurrence, volcanic material content (Vm), and rhythmic mineralogical variations. The two stages exhibit similar organic matter types and thermal maturity, indicating that these factors did not control the observed TOC differences. All anomalously high TOC intervals occur in the SVAS. Proxy data indicate that the NVAS was deposited under hot, arid, saline, shallow-water, and strongly reducing conditions in which organic matter enrichment was primarily controlled by preservation. During the SVAS, volcanic activity likely moderated the hot and arid climate, intensified chemical weathering, deepened the lake, reduced salinity, weakened persistent bottom-water reduction, and increased redox variability. At the same time, paleoproductivity increased significantly compared to the NVAS. Volcanism thus reorganized the lake system by modifying hydroclimate, basin hydrology, water chemistry, and nutrient supply, thereby shifting the dominant control on organic matter enrichment from preservation to productivity. These results provide a process-based explanation for volcanism-driven source-rock development in saline lacustrine basins.

17. 题目: Zinc isotope fractionation during the interaction with different molecular weight fractions of dissolved organic matter
文章编号: N26051420
期刊: Applied Geochemistry
作者: Qiyuan Liu, Yaqin Zhang, Zening Lü, Tongying Yan, Rui Zuo, Yuanzheng Zhai, Liuting Song
更新时间: 2026-05-14
摘要: The bioavailability and mobility of zinc (Zn) are predominantly governed by dissolved organic matter (DOM) in natural environments. Although Zn isotopes are known to fractionate during complexation with organic ligands, the mechanism of how DOM heterogeneity modulates this process remains poorly constrained. In this study, we investigated Zn isotope fractionation induced by complexation with different molecular weight (MW) fractions of two natural DOM: Pahokee Peat Fulvic Acid (PPFA) and Suwannee River Fulvic Acid (SRFA). The Donnan Membrane Technique (DMT) was employed to separate Zn-DOM complexes from free Zn species. The results indicate that while no discernable isotopic fractionation was observed ( = −0.12‰ to +0.06‰) induced by bulk PPFA and SRFA, the MW-fractionated components displayed a broad range of distinct isotopic fractionation ( = −0.01‰ to +0.55‰). For PPFA fractions, heavy Zn isotopes are preferentially enriched in the Zn complexes ( = +0.28‰ to +0.30‰), which is attributed to the formation of strong, stable bonds with abundant aromatic phenolic moieties, particularly within the high-MW fractions. SRFA components exhibited more pronounced isotopic fractionation compared to PPFA, with values reaching up to +0.55‰ for the 100–1000 kDa fraction and +0.53‰ for the <10 kDa fraction. This enhanced fractionation is primarily attributed to the formation of stronger inner-sphere complexes with shorter Zn-ligand bond lengths, likely involving coordination with carboxyl and/or hydroxyl functional groups. This study reveals how structural and functional group differences among different MW fractions of DOM affect metal complexation capacity and consequently influence Zn isotope fractionation, providing a better understanding of Zn biogeochemical cycling in natural systems.

18. 题目: Soil organic carbon response to no-till is conditioned by edaphoclimatic moderators in tropical agriculture: Evidence from Brazil
文章编号: N26051419
期刊: Soil and Tillage Research
作者: Altene JEAN-LOUIS, Giulia Ketlen SANCHES, Sérgio Abílio AZEVEDO, Johnny JEAN, Bruno Montoani SILVA, Ana Carolina BARBOSA, Samara Martins BARBOSA, Jessica Oliveira Notorio RIBEIRO, Renan PREVIL, Vânessa Lopes de FARIA, Rafaella Tatiane Silva de SÁ, Juliano Vilela OLIVEIRA, Junior Cesar AVANZI
更新时间: 2026-05-14
摘要: Fixed-depth soil sampling can bias soil organic carbon (SOC) stock comparisons between no-tillage (NT) and conventional tillage (CT) when bulk density differs between systems, yet many tropical syntheses have not corrected for this effect. A systematic review compiled 46 studies from 58 sites across five Brazilian biomes, Cerrado, Mata Atlântica, Amazônia, Caatinga, and Pampa, and applied a CT-anchored equivalent soil mass (ESM) framework to harmonize SOC stocks across cumulative depth strata of 0–20, 0–40, 0–60, and 0–100 cm. The dataset was dominated by Ferralsols (Latossolos, Oxisols), Cambisols (Cambissolos, Inceptisols) and Acrisols (Argissolos, Ultisols). In the paired meta-analytic subset, NT increased SOC stocks by 18% relative to CT (NT/CT = 1.18, 95% CI: 1.11–1.26), although the prediction interval (0.84–1.74) indicated substantial context dependence. ESM-standardized profiles showed that gains extended to 0–60 cm in the Cerrado and Mata Atlântica, whereas responses were near zero in the Caatinga and largely surface-confined in Amazônia. Time since NT adoption was not a significant moderator, despite NT showing higher SOC stocks throughout the entire evaluated period. In moderator analyses of SOC stocks under NT, clay content showed a positive association, whereas mean annual rainfall showed a negative association. These findings demonstrate that mass-corrected, profile-integrated accounting substantially alters estimates of NT mitigation potential in tropical agroecosystems and underscore the need for carbon accounting frameworks to incorporate ESM approaches and stratification by texture and moisture regime to avoid systematic bias in cross-climate comparisons. Such integration is relevant for Measurement, Reporting, and Verification systems supporting national climate commitments, including Brazil’s Nationally Determined Contribution and Low Carbon Agriculture Plan, but is equally applicable to global assessments of conservation agriculture.

19. 题目: Hierarchical porous biochar with enhanced performance inspired by “corn straw/cow manure co-compost” designed for efficient removal of antibiotics
文章编号: N26051418
期刊: Environmental Technology & Innovation
作者: Yuhan Zheng, Ziyu Guo, Ruihangyi Zhang, Siji Chen, Chunjie Tian, Shanshan Tang, Guang Chen
更新时间: 2026-05-14
摘要: In this study, corn straw (CS) was processed using two pretreatment routes, namely corn straw/cow manure co-composting and solid fermentation with a homologous microbial community isolated from cow manure. The pretreated materials were converted into biochar (BSC-3 and BSF-3) through carbonization-activation. Changes in microbial communities and their effects on straw composition and structural characteristics were investigated through comparative dynamic analysis. The characterization results indicated that compared with the biochar produced directly from raw straw without pretreatment (BCS), the biochars derived from both co-composting and solid fermentation pretreatments exhibited superior physicochemical properties. The specific surface areas of BSC-3 and BSF-3 were 2946.21 and 2504.56 m2/g, respectively. The total pore volumes increased to 1.8422 and 1.4721 cm3/g, representing increases of 45.6–71.3% and 47.2–79.4% over BCS. This enhancement was mainly attributed to two factors. First, microbial pretreatment disrupted the lignocellulosic structure, thereby generating more porous precursors for activation. Second, the mycelial structures introduced during microbial modification contributed additional microstructural features favorable for biochar formation. In adsorption experiments using hydrochloric tetracycline (TH) and sodium sulfadiazine (SD-Na) as model antibiotics, the biochars exhibited outstanding adsorption performance. The maximum adsorption capacities reached 1513.56 and 1422.45mg/g for TH, and 1281.65 and 1258.85mg/g for SD-Na, exceeding those of previously reported adsorbents. In addition to producing high-performance biochar for efficient antibiotic removal from water, this study verified the feasibility of microbial community pretreatment for improving the functionality of the derived biochar, providing a promising strategy for the development of lignocellulosic biochars.

20. 题目: Hierarchical FeWO4@biochar triggering efficient interfacial charge transfer for photocatalytic CO2 reduction and sulfamethazine degradation
文章编号: N26051417
期刊: Journal of Environmental Chemical Engineering
作者: Jie Wan, Lei Chen, Siyu Du, Changjian Zhang, Yunchang Peng, Xiaofan Yang
更新时间: 2026-05-14
摘要: The integration of biomass-derived carbon supports with semiconductor catalysts represents an effective and sustainable approach to improving photocatalytic performance for energy and environmental applications. In this work, a dual-functional ferrous tungstate-biochar composite (FeWO4@biochar) was synthesized via hydrothermal method and independently evaluated for visible-light-driven CO2 reduction and sulfamethazine (SMZ) degradation. SEM, TEM, and density functional theory (DFT) calculations confirmed the uniform in-situ growth of flower-like FeWO4 nanostructures and their strong interfacial anchoring on the biochar surface, resulting in a well-contacted heterointerface that triggers rapid interfacial electron migration. The generation of key intermediate *COOH was confirmed by the In-situ FTIR analysis, which are essential for CO2 conversion to CO. The FeWO4@biochar attained a CO yield of 13.23 μmolg⁻¹h⁻¹, while 93.7% SMZ degradation was attained within 120min under visible light. LC-ESI/MS analysis was employed to elucidate plausible SMZ degradation pathways, while ECOSAR 2.0 indicated substantial toxicity reduction after photocatalytic treatment. In addition, DFT deformation charge density calculations and in-situ XPS results revealed directional electron transfer from FeWO4 to biochar, which triggers efficient interfacial charge-transfer pathways governing both CO2 reduction and SMZ mineralization. These results providing guidance for designing multifunctional FeWO4-based photocatalysts for solar energy conversion and pollutant remediation.