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121. 题目: Influence of polarity and charge on fractionation and treatability of organic matter during drinking water treatment: lab study and field application
文章编号: N25112805
期刊: Water Research
作者: Yu Wang, Yuxuan Xie, Zhiwei Ye, Fan Zhou, Jun Wang, Irwin Mel Suffet, Chao Chen
更新时间: 2025-11-28
摘要: Understanding the general properties of dissolved organic matter (DOM) is crucial for optimizing water treatment processes to remove DOM and enhancing the drinking water quality. However, the chemodiversity of DOM as a mixture of various organic chemicals in water poses significant challenges to understanding comprehensively its sources, fate and treatability during water treatment train. In this study, polarity and charge of DOM determined by the Polarity Rapid Assessment Method (PRAM) were used as two of key parameters of chemodiversity to elucidate its distribution and changing patterns in source waters and along the water treatment processes. Our evaluation suggests that the intracellular organic matter (IOM) from algal metabolism during blooms may explain the observed increase in positively charged fraction of DOM in source water. During water treatment process, coagulation and sedimentation primarily removed the negatively charged fraction of DOM, while ozonation was more effective at removing the non-polar fraction. Additionally, we investigated the retention mechanism of specific fractions by PRAM approach using model compounds such as amino acids containing specific functional groups. This revealed the structural characteristics of the different polar and charge fractions. Propane sulfonate in strong cationic exchange SPE used in PRAM electrostatically interacts with compounds containing protonated basic groups. In their deprotonated state, basic groups are retained on the cartridge via hydrogen bonds, likely due to a sufficient number of hydrogen bond donor sites. Thus, the PRAM method enhances the understanding of the sources and fate of DOM chemodiversity in drinking water and this can guide the assessment and optimization of drinking water treatment processes.

122. 题目: Hydraulic manipulation enhances 1,2-dichlorobenzene (DCB) removal in porous aquifers by zero-valent iron/biochar reactive barriers: Mechanistic insights from sandbox validation and TMVOC simulations
文章编号: N25112804
期刊: Journal of Hazardous Materials
作者: Xinbo Yao, Junxiang Shi, Tingting Wang, Qingquan Zhang, Shuyuan Zhu, Jichun Wu, Hongyan Guo
更新时间: 2025-11-28
摘要: Groundwater contamination by dense non-aqueous phase liquids (DNAPLs) remains a persistent challenge due to their low solubility, high density, and complex subsurface behavior. Permeable reactive barriers (PRBs) provide in situ treatment, yet their efficiency is often constrained by limited plume–barrier contact. Here, we investigate the coupling of PRBs with hydraulic manipulation strategies—pumping-only and dual-well recirculation—to enhance DNAPL removal. PRBs composed of zero-valent iron (ZVI), biochar, diatomite and bentonite were applied for in situ removal of 1,2-dichlorobenzene (DCB), a representative chlorinated DNAPL. Large-scale sandbox experiments combined with TMVOC-based numerical simulations revealed that hydraulic regulation significantly modified plume distribution and geochemical conditions within the PRB. The dual-well system increased plume–PRB contact area, accelerated mass transfer, and reduced remediation time by 24.2% in sandbox experiments and 27.6% at the field scale. Geochemical monitoring showed that hydraulic manipulation enhanced alkaline and reductive microenvironments (pH up to 12.0; ORP down to –80 mV), which promoted reductive degradation of DCB. Microbial community analysis indicated that biochar-supported bacteria capable of degrading chlorinated aromatics were selectively enriched under coupled conditions, suggesting a synergistic contribution of biotic and abiotic pathways. This work highlights the mechanistic benefits of integrating hydraulic control with PRBs, revealing how flow-field manipulation alters contaminant transport, geochemical conditions, and microbial activity. The findings provide a process-level understanding of coupled hydraulic–reactive systems and offer guidance for designing more robust and sustainable in situ remediation strategies for DNAPL-contaminated aquifers.

123. 题目: Increased drought intensity stimulates the extracellular polymeric substance accumulation and their contribution to soil organic carbon rather than microbial necromass
文章编号: N25112803
期刊: Soil Biology and Biochemistry
作者: Huijun Li, Baorong Wang, Haoning Chen, Na Li, Yue Zhou, Zhaolong Zhu, Jinshi Jian, Gurpal S Toor, Shaoshan An
更新时间: 2025-11-28
摘要: Beyond the recognized role of microbial cell wall residues in soil organic carbon (SOC), microbes under drought stress appear to strategically divert C toward the production of extracellular polymers (EPS), positioning them as a dynamic C pool. Their contrasting environmental behavior and turnover create a fundamental uncertainty in predicting SOC dynamics in drying ecosystems. Despite their importance, the dynamics of EPS and microbial necromass (indicated by amino sugars) under prolonged drought, their relative contributions to SOC accumulation, and the factors regulating them remain poorly constrained. We hypothesized that intensified drought would preferentially stimulate EPS accumulation over microbial necromass, as microbes divert more C toward EPS synthesis to mitigate water stress. To test this, a 9-year drought experiment was conducted with four treatments (control and 20%, 40%, and 60% reductions). We found that under prolonged drought, the contents of both EPS and microbial necromass declined, with the former decreasing by 30.2% and the latter more sharply by 76.0% under extreme conditions, indicating their asynchronous formation and accumulation. However, increasing drought intensity enhanced the EPS accumulation coefficient rather than that of microbial necromass, indicating a greater microbial C investment in EPS production and higher formation efficiency under water stress. Long-term drought also restructured the microbial community, shifting C allocation from biomass growth and necromass formation (associated with taxa like Proteobacteria and Ascomycota) toward EPS production (e.g., Bacteroidota, Basidiomycota and Glomeromycota). In parallel, abiotic variables such as Olsen phosphorus, nitrate, and ammonium were tightly coupled to EPS accumulation, underscoring EPS role in sustaining bioavailable nutrient pools as soil moisture declines. Collectively, these findings provide direct evidence that EPS contributes more actively to SOC than microbial necromass. The strategic shift in microbial carbon from necromass to EPS buffers SOC pools,with important implications for ecosystem C cycling and climate feedbacks under drought.

124. 题目: Financial feasibility of biochar production: A comparative analysis of business scenarios
文章编号: N25112802
期刊: Journal of Cleaner Production
作者: Ana Carolina Morim, Mara Madaleno, Luís A C Tarelho, Flávio C Silva
更新时间: 2025-11-28
摘要: The climate crisis is a global challenge that demands action. Portugal is committed to achieving carbon neutrality; however, a recurring obstacle is wildfires. An effective way to prevent wildfires is the removal of excess biomass as the shrubs and other residual biomass from forestry operations (e.g., tree tops), which act as a vector for fire propagation. To stimulate operations of forestry management and maintenance through the valorization of residual biomass, an economic incentive is required. To address this, a technoeconomic analysis was developed to assess the economic potential of valorizing residual forestry biomass for biochar production. Three business scenarios were created, differing in revenue: 1 - Biochar and carbon credits; 2 - Forest management operations, biochar, and carbon credits; 3 - Forest management operations, biochar, carbon credits, and sale of surplus biomass. All scenarios assumed the use of an autothermal decentralized pyrolysis reactor. Economic viability was assessed using Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PP). Scenario 1 had a negative NPV of € −1,360,620. In contrast, scenarios 2 and 3 were viable, with NPVs of € 172,426 and € 685,234, respectively. Scenario 2 had an IRR of 7 % and a PP of 15 years, while scenario 3 achieved an IRR of 13 % and a PP of 8 years. Sensitivity analysis identified key variables influencing NPV. Results show that integrating the entire production chain significantly improves the financial viability of biochar production, offering a sustainable solution to forest management challenges while contributing to decarbonization efforts.

125. 题目: Biochar accelerated soil atrazine degradation by promoting dechlorination pathway: A novel mechanism revealed by DNA stable isotope probing (DNA-SIP)
文章编号: N25112801
期刊: Bioresource Technology
作者: Guiqiong Yang, Zhen Zhen, Kun Zhang, Junyong Yin, Xiaolan Zhong, Xiaofeng Li, Qing Li, Kaijiang Nie, Xiaoyang Miao, Zhong Lin, Dayi Zhang
更新时间: 2025-11-28
摘要: Biochar can accelerate atrazine degradation in soils, with surface modification being a widely accepted method to improve the performance. Nevertheless, the underlying mechanisms remain unclear. This study explored the efficiency of modified biochar in facilitating soil atrazine biodegradation with the aid of DNA stable isotope probing (DNA-SIP) and metabolite profiling. DNA-SIP results confirmed the involvement of ten bacterial genera and six atrazine degradation-related genes in atrazine metabolism in situ. Among them, Candidatus Nitrososphaera, Pedosphaera and Conexibacter were reported to be associated with atrazine degradation for the first time. FeCl3-modified biochar significantly accelerated atrazine degradation (85%) by improving soil physicochemical properties (pH, soil organic matter and humus) and enriching the active atrazine degraders. Notably, atrazine dechlorination pathway was preferentially promoted by modified biochar. The findings suggested that DNA-SIP enabled the discovery of the active atrazine degraders and degradation-related genes in biochar-amended soils, providing novel insights into the mechanisms of biochar-facilitated atrazine removal.

126. 题目: Effect of Pisha Sandstone and Biochar on Improving the Physical Properties of a Sandy Soil Under Constant Mechanical Stress
文章编号: N25112715
期刊: Land Degradation & Development
作者: Xiao Yu, Lidong Ren, Xiaoxu Jia, Yuhao Dong, Mingbin Huang
更新时间: 2025-11-27
摘要: Soils in the Jin-Shaan-Meng region are prone to erosion and poor water retention, restricting agricultural productivity. Despite the known benefits of soil amendments like Pisha sandstone and biochar, their combined effects on sandy soil properties remain underexplored, particularly under constant mechanical stress conditions. We conducted a controlled indoor incubation with combinations of five Pisha sandstone ratios (0%, 25%, 50%, 75%, 100%) and three biochar application rates (0%, 2%, 4%) under constant mechanical stress, measuring bulk density, shear strength, hydraulic conductivity, water retention, and X-ray micro-computed tomography (X-ray micro-CT) derived soil structure. The results indicate that both amendment materials significantly increased soil compressibility, as evidenced by decreased bulk density driven by Pisha sandstone's silt-clay fractions optimizing soil particle arrangement, and biochar's low particle density plus porous structure buffering particle compression under constant mechanical stress. However, no significant difference in bulk density was observed between the 2% and 4% biochar treatments. Soil erodibility, assessed through shear strength and aggregate size distribution, was generally increased with biochar alone but substantially reduced at 25%–50% Pisha sandstone content combined with 4% biochar, caused by their synergistic interaction: biochar acts as a “cementing agent” and Pisha sandstone provides skeletal support to enhance inter-particle occlusion. X-ray micro-CT analysis revealed improved pore structure with the incorporation of biochar and Pisha sandstone by increasing pore connectivity and micropore abundance. Soil water retention was markedly enhanced at the 4% biochar rate, underscoring the critical role of biochar in improving the physical properties of sandy soil.

127. 题目: Slope Aspect Influences the Organic Carbon Content and Stock in Soil Aggregates of Cut Slopes in the Alpine Region of Southwest China
文章编号: N25112714
期刊: Land Degradation & Development
作者: Shenghao Ai, Mei Chen, Meihua Sheng, Xiaoyan Ai
更新时间: 2025-11-27
摘要: Road construction in alpine regions generates extensive bare cut slopes, which aggravates soil erosion and leads to substantial loss of soil organic carbon (SOC). Slope aspect modifies hydrothermal conditions, making it a critical regulator of SOC dynamics; however, it is unclear how it affects the physical protection of SOC within various soil aggregates in engineered cut slopes. In this study, we investigated the distribution and drivers of soil-aggregate-associated SOC across four slope aspects [south-, west-, east-, and north-facing (SFS, WFS, EFS, and NFS, respectively)] in the alpine region of Southwest China. Wet sieving for aggregate separation and partial least squares path model (PLS-PM) for causal inference demonstrated that SOC content and stock in both bulk soil and aggregate fractions systematically varied with slope aspect type, generally following the order NFS > EFS > WFS > SFS. Small macroaggregates (SMA) and microaggregates (MIA) were identified as the dominant SOC reservoirs. Their combined dominance was the most pronounced in SFS, WFS, and EFS. PLS-PM revealed that slope aspect type did not directly influence aggregate-associated SOC but indirectly influenced it by affecting soil water content, total nitrogen, and soil organic matter (R² = 0.84). These factors governed the composition of soil aggregates and the SOC amount associated with them, which ultimately served as the most direct and decisive controls on total SOC dynamics (R² = 0.99). Our findings demonstrated that the stabilization of carbon in SMA and MIA is the central mechanism underlying slope-aspect-driven SOC sequestration patterns in these systems. This mechanistic insight offered a scientific basis for designing aspect-specific restoration strategies to enhance carbon storage and soil quality in engineering and road construction projects in alpine regions.

128. 题目: Urinary and tissue black carbon and their impact on kidney function in transplant recipients
文章编号: N25112713
期刊: Environmental Pollution
作者: Leen Rasking, Kenneth Vanbrabant, Liesa Engelen, Michelle Plusquin, Katrien De Vusser, Tim S Nawrot
更新时间: 2025-11-27
摘要: Air pollution, particularly exposure to black carbon (BC) nanoparticles, has been linked to adverse kidney outcomes. Transplant recipients may be especially vulnerable, making investigation of environmental influences on kidney function in this subpopulation essential. Building on recent evidence that BC nanoparticles can translocate into urine and kidney tissue, this study explores the link between internal and external air pollution on kidney function in transplant recipients one year post-transplantation. We included 183 kidney transplant recipients with protocol biopsies and 24-h urine samples between October 2019 and December 2023. BC in tissue and urine was assessed using white-light generation under femtosecond-pulsed illumination. Kidney function biomarkers were evaluated in association with modelled PM_2.5 and BC, proximity to a major road, and tissue and urinary BC using Pearson correlation and linear regression. Each 10% increase in urinary BC was associated with a 14.24 mg/dL increase in urinary urea (95%CI: 10.83, 17.64; p<0.01), a 2.71% increase in KIM-1 (95%CI: 1.85, 3.59; p<0.01), a 4.47% increase in microalbumin (95%CI: 0.89, 4.88; p<0.01), a 4.60% increase in alpha-1-microglobulin (95%CI: 2.58, 6.67; p<0.01), and a 0.02 mg/dL reduction in urinary creatinine clearance (95%CI: -0.03, -0.01; p<0.01). Tissue BC was borderline associated with reduced eGFR (0.20 mL/min/1.73 m²; 95%CI: -0.42, 0.02; p=0.07). Living farther from a major road was associated with lower urinary KIM-1 (-1.28%; 95%CI: -2.16, -0.40; p<0.01) and reduced urinary urea (-5.00 mg/dL; 95%CI: -8.84, -1.16; p=0.01). In kidney transplant patients, urinary BC was significantly associated with biomarkers of glomerular and tubular kidney damage. Additionally, living farther from major roads correlated with improved kidney function, emphasizing the impact of e.g., BC accumulation on post-transplant kidney health.

129. 题目: Unraveling the distribution and stability of deep soil organic carbon after long-term conservation tillage practices
文章编号: N25112712
期刊: Soil and Tillage Research
作者: Jianye Li, Yong Zhu, Na Li, Yunying Fang, Xiaolin Dou, Yuanyuan Lu, Xingyi Zhang, Bojie Fu, Chunlong Liu, Shuguang Liu, Xinqiang Liang
更新时间: 2025-11-27
摘要: The dynamics of soil organic carbon (SOC) in deep soil layers (below 20 cm) represent a critical uncertainty in assessing the carbon sequestration potential of conservation agriculture. This study unravels the response of SOC distribution and stability to 15 years of no-till with straw mulching (NT) versus conventional tillage (CT) in a boreal agroecosystem. Our findings indicate that NT notably enhanced active SOC fractions in deep soil (DS), with increases observed in microbial biomass carbon (MBC) by 104 %, particulate organic carbon (POC) by 112 %, light fraction organic carbon (LFOC) by 42 %, and dissolved organic carbon (DOC) by 22 %. More importantly, NT fundamentally altered the composition and stability of the deep SOC pool. It enhanced the stability of microbial necromass carbon (MNC) in DS by elevating the fungal-to-bacterial necromass carbon ratio. Additionally, plant-derived carbon (PDC) demonstrated increased stability in DS under NT, indicated by a 58 % reduction in (Ac/Al)s values, a 28 % decrease in (Ac/Al)v values, and an 84 % increase in V-type phenols. In the 20–100 cm layer, FNC and MBC emerged as key factors influencing SOC contents. Our findings suggest that long-term NT farming fundamentally transforms the distribution and stability of SOC in DS. It not only enriches labile carbon pools but also promotes a shift towards a more persistent carbon pool dominated by fungal necromass and physically protected plant-derived compounds in deep soil. This demonstrates that long-term NT fundamentally affects SOC fractions, origins and stability in DS, providing new insights into carbon biogeochemical cycling under long-term conservation tillage and highlighting its potential to enhance carbon sequestration beyond the topsoil in agricultural systems.

130. 题目: Mechanistic links between phosphorus activators and organic phosphorus mineralization: Phosphatase-mediated responses in soils with contrasting microbial activity
文章编号: N25112711
期刊: Applied Soil Ecology
作者: Chenran Wu, Nan Jiang, Yulan Zhang, Dongqi Jiang, Shuqiang Wang, Jingmin Hu, Zhenhua Chen, Lijun Chen
更新时间: 2025-11-27
摘要: Phosphatase-mediated mineralization of soil organic phosphorus (P) critically governs P bioavailability in agricultural systems, yet microbial regulation of phosphatase dynamics under P-activator amendments remains poorly resolved. We investigated six P-activator treatments—phytase (S1), phosphate-solubilizing microorganisms (PSM, S2), and their combinations with yeast-derived peptides (S13, S23, S123)—in soils with contrasting microbial activity (soilhigh vs. soillow) over 35 days. Analyses focused on phosphatase (including acid phosphomonoesterases [AcP], alkaline phosphomonoesterases [AlP], and phosphodiesterases [PD]) activities, dehydrogenases (DHA) as a proxy for metabolic activity, and available P. The results revealed P-activators universally enhanced soil AcP and AlP activities and available P release, with synergistic effects in combined treatments (S123 > S13/S23 > S1/S2 > control). Temporal dynamics differed between soils, PD activity in soilhigh increased consistently post-day 3 (excluding day 14), while soillow exhibited a pronounced increase in AcP or AlP activity during days 1–28 but limited PD or DHA responses. Microbial activity modulated activator efficacy by stimulating phosphatase activities, evidenced by sustained DHA elevation (days 1–21) and its significantly correlation with the variation in APases activities. Except for S2, the stimulation of AcP activity by the activators was significantly greater in soilhigh compared to soillow. In contrast, S1, S13, and S2 enhanced PD activity more strongly in soillow. Additionally, S1 and S2 led to a more pronounced increase in available P content in soillow than in soilhigh. Crucially, microbial-driven DHA activity strongly correlated with the functional role of phosphatases in releasing available P, highlighting microbial-phosphatase coordination as a central mechanism in P-activator efficacy. These findings demonstrate that tailored P-activator combinations can optimize soil-specific P mobilization, providing a technical strategy to improve P use efficiency and reduce fertilizer dependency in sustainable agriculture.

131. 题目: Study on the efficiency of co-composting of nitrobenzene-contaminated soil and cow manure enhanced by manganese dioxide modified biochar and synthetic microbial communities
文章编号: N25112710
期刊: Journal of Environmental Management
作者: Mengmeng Zhang, Shenghui Wang, Chenglong Fu, Hui Qi, Junxing Zhu, Jie Li, Fengting Qu, Zimin Wei, Caihong Song
更新时间: 2025-11-27
摘要: Composting shows high potential to remediate nitrobenzene (NB)-contaminated soils. However, it currently suffers from inefficient NB degradation and limited humification. In this study, a co-composting experiment involving cow manure and NB-contaminated soil was conducted to investigate the effects of MnO2 (Mn group), MnO2-modified biochar (MBC, B group), and a high-efficiency NB-degrading synthetic microbial community (SynComs, J group) on the efficiency of co-composting, as well as their potential biological and abiotic roles. The results demonstrated that high NB degradation rates were observed in all treatments, with groups J (99.69 %) and Mn (99.67 %) having the highest NB degradation rates. Both addition of functional materials and inoculation with SynComs significantly promoted the humification process. The humification index of groups J, Mn and B increased by 25.62 %, 12.20 % and 2.44 %, respectively. Both Procrustes analysis and correlation analysis confirmed that inoculation with SynComs and addition of functional materials strengthened the direct correlation between NB degradation and humus synthesis. Enhanced laccase/polyphenol oxidase/protease activity drove cellulose/lignin breakdown, and their hydrolysates boosted humus formation, sharply advancing humification. Inoculation with SynComs was most beneficial for microorganisms to utilize total sugar, polyphenols and convert them into more stable humus. Without additives, natural co-composting mineralizes rather than humifies organic matter degradation products. Bacterial composition and diversity in group J played an important role in humus biosynthesis. The addition of both MnO2 and MBC boosted biotic humus synthesis, while MBC also promoted abiotic condensation in humus formation. This study offered practical guidance for enhancing the efficiency of co-composting in remediating NB-contaminated soil.

132. 题目: Biophysical and management drivers of soil organic carbon accumulation in operational farms across Tennessee, USA
文章编号: N25112709
期刊: Soil and Tillage Research
作者: Rasu Eeswaran, Patricia A Lazicki, Alemu Mengistu, Sindhu Jagadamma
更新时间: 2025-11-27
摘要: While various factors influence SOC accumulation, region-specific drivers in producer-managed farms remain unclear, especially beyond the surface layer (∼30 cm), where research has been limited. To address this gap, we quantified SOC stocks at 0–5, 5–15, 15–30, 30–45, and 45–60 cm depths from 22 operational crop and pasture farms, adopting a range of soil health practices, located in three Major Land Resource Areas (MLRAs) in Tennessee, USA. Biophysical variables such as normalized difference vegetation index (NDVI), slope, and climatic variables were collected. Management variables were assigned qualitative scores based on information collected from field surveys. Depth-specific regression models were developed to elucidate drivers of SOC stock and their relative importance (RI). SOC stock and stratification ratio showed significant responses to management practices, and these responses were prominent in shallow depths compared to deeper layers. Intensively managed rotational pastures with long duration presence of livestock and long-term no-till (i.e., 38-years) row crop systems with organic inputs significantly increased SOC stock compared to other managed systems. SOC accumulation is influenced by land use and soil depth. Precipitation and NDVI were dominant drivers in the topsoil across both crop and pasture systems (RI: 55–56 %). In crop farms, cropping diversity (RI: 14 %) and organic inputs (RI: 17 %) emerged as key management factors. Subsoil SOC stock was primarily shaped by biophysical drivers (RI: 76 %)—precipitation, NDVI, and clay—with residue retention (RI: 24 %) being the sole management factor. In pastures, grazing management played a critical role in the topsoil (RI ∼25 %), while clay became increasingly important in deeper layers (RI: 25–47 %) across both systems. These findings highlight the importance of combining cropping diversity, residue retention, organic amendments, and strategic grazing management to enhance SOC stocks and improve soil health; both contributing to high productivity.

133. 题目: The benthic environment of the Aleutian Trench region: Sediment provenance, organic carbon sources and deposition dynamics
文章编号: N25112708
期刊: Progress in Oceanography
作者: M B Sindlev, J P Balmonte, F Wenzhöfer, W Xiao, P Stief, K Oguri, M Tsuchiya, Y Yokoyama, A Rudra, D E Canfield, H Sanei, A Brandt, R N Glud
更新时间: 2025-11-27
摘要: Sedimentological, mineralogical, chronological and basic biogeochemistry document that the Aleutian Trench region consists of four distinct regions, each with their respective benthic habitat, deposition dynamics, and material sourcing: the Northern Aleutian Slope (NS), Aleutian Trench – Axis (AT-A), Aleutian Trench – South Slope (AT-SS), and Southern Aleutian Slope (SS). The carbon pool is characterized by pyrolysis derived hydrogen and oxygen indices (HI and OI), radionuclides (Δ14C) and stable isotopes (δ13C-values), clearly varying among the respective regions. The NS has elevated total organic carbon (TOC) content, including distinct imprint of fresh, marine-derived organics originating from upwelling in the Gulf of Alaska with subsequent westward transport by the Alaskan Stream, sustaining high remineralization rates, with well-defined infaunal burrow structures in the sediment. Stations at the AT-A have a 2.5–24.1 cm thick, glacially derived fluid mud layer (FML) deprived of infauna, blanketing the original sediment surface. Chronological markers document that the infilling of the FML happened since the mid 1950′s and now extends to at least one fifth of the entire Aleutian Trench axis. The FML contains a mixture of fresh, marine-derived and recalcitrant terrigenous organics, with elevated microbial mineralization rates, presumably enhanced by microbial priming and efficient microbial degradation of otherwise recalcitrant organics. The AT-SS and SS have low TOC contents, exhibit very low microbial remineralization rates, with only sparse infaunal imprints. Our investigations document that the Aleutian Trench forms a unique hadal environment, while simultaneously confirming that hadal trenches generally act as depocenters with intensified microbial activity, sustained by various sources of organics.

134. 题目: Wet-Mechanochemical Enteromorpha-Derived Biochar Nanoparticles for Efficient Remediation of Cd- and Pb-Contaminated Soil
文章编号: N25112707
期刊: Water, Air, & Soil Pollution
作者: Sehar Anum, Sheng Liu, Peng Zhang, Srđan D Rončević, Hongwen Sun
更新时间: 2025-11-27
摘要: The utilization of low-cost seaweed biomass waste for biochar (BC) production has been demonstrated to be an effective solution in remediating heavy metals (HMs)-contaminated soil, thereby enhancing soil health and mitigating the environmental risks associated with HMs contamination. This study successfully synthesized and characterized a novel Enteromorpha-derived BC nanoparticles (MEBC-900) from Enteromorpha by wet-mechanochemical sand milling and applied it to remediate Cd2+- and Pb2+-contaminated soil. Sand milling significantly increased the specific surface area of MEBC-900 (466.5 m2/g) by reducing it into nanosized particles and enriching it with abundant O- and N-functional groups. These modifications improved its adsorption for HMs, achieving 68.9 mg/g for Cd2+ and 170.8 mg/g for Pb2+ through the surface complexation, electrostatic interaction and precipitation. The adsorption kinetics and isotherm analysis conformed to the pseudo-second-order and Langmuir models, confirming that monolayer chemisorption is the primary mechanism. Pot experiments demonstrated that MEBC-900 improved soil conditions, including increasing soil pH, organic matter, and nutrient level while promoting microbial community. Furthermore, MEBC-900 effectively enhanced the immobilization of Cd2+ and Pb2+ in soil, reducing their accumulation in maize by 52% and 43%, respectively. It also facilitated oxidative stress in maize by reducing malondialdehyde levels by 40% and enhancing plant enzymatic activity under Cd2+ and Pb2+ stress conditions. This study presents a promising and low-cost sand-milled adsorbent (MEBC-900) for the remediation of HM-contaminated soil.

135. 题目: Reductive Dechlorination of Trichloroethene by Carboxymethyl Cellulose Stabilized and Sulfidated Nanoscale Zero-Valent Iron: Effect of Humic Acid
文章编号: N25112706
期刊: Water, Air, & Soil Pollution
作者: Bo Chen, Qi Li, Yuhan Hang, Si Chen, Zihan Xie, Hao Yuan, Yadong Yang, Feng He
更新时间: 2025-11-27
摘要: Carboxymethyl cellulose stabilized and sulfidated nanoscale zero-valent iron (CMC-S-nZVI) has demonstrated considerable promise for the in-situ dechlorination of trichloroethylene (TCE) in groundwater. However, the effects of natural groundwater components, notably humic acid (HA), on the reactivity and electron efficiency (εe) of CMC-S-nZVI remains unclear. This study investigated the degradation of TCE by both sulfidated and unsulfidated CMC-nZVI particles in the presence of HA. Compared to CMC-nZVI, the dechlorination rate constant of TCE by CMC-S-nZVI increased by 40 times (from 0.01 h−1 to 0.47 h−1), enabling the complete conversion of TCE to ethylene within 10 h. The dechlorination rate of CMC-S-nZVI decreased with the addition of HA, while the electron efficiency increased from 44 to 75%. This phenomenon is attributed to HA decreasing the reduction of water by CMC-S-nZVI, thereby optimizing the process and enhancing its efficiency for TCE degradation. Furthermore, HA inhibited the hydrogenation of acetylene to ethylene by CMC-S-nZVI during TCE dechlorination, as it suppressed H2 generation by CMC-S-nZVI. The effect mechanism of HA on the dechlorination of CMC-S-nZVI provides a scientific foundation for optimizing the application in actual polluted groundwater remediation.

136. 题目: Precipitation increase promotes soil organic carbon formation and stability via the mycorrhizal fungal pathway
文章编号: N25112705
期刊: Proceedings of the National Academy of Sciences of the United States of America
作者: Tangqing He, Yunfeng Zhao, Xiaodong Wang, Yunpeng Qiu, Jun Deng, Kangcheng Zhang, Xinyu Xu, Yexin Zhao, Kaiyun Qian, Hao Wang, Tongshuo Bai, Yi Zhang, Cheng Feng, Lijin Guo, Huaihai Chen, Liang Guo, Yi Wang, Shuijin Hu
更新时间: 2025-11-27
摘要: Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with roots of most terrestrial plants, playing a crucial role in regulating soil organic carbon (SOC) dynamics. While precipitation increase (Pi) is a major facet of climate change, its impacts on root- and AMF-mediated SOC formation and stability remain largely unexplored. Here, we combined a meta-analysis across global grasslands with a multiyear precipitation manipulation experiment in a semiarid grassland on the Loess Plateau to disentangle the relative effects of roots and their associated AMF on microbial communities and SOC as influenced by Pi. We show that Pi induced tradeoffs between roots and AMF, and promoted SOC formation and stability via the mycelium- rather than the root-pathway, leading to an increase of 136% (±40) and 297% (±90) in mycelium-derived C and mineral-associated organic C (MAOC), respectively. Pi altered plant community composition, favoring subshrubs and forbs over grasses. Also, Pi reduced specific root length, but increased root diameter, tissue density, and root colonization and extraradical biomass of AMF. Furthermore, Pi-induced change in AMF shifted the soil bacterial community by favoring K-strategists, increasing bacterial necromass C and promoting MAOC accumulation. Our findings provide direct evidence that Pi enhances AMF-driven SOC sequestration by expanding the mycorrhizosphere and promoting microbiota with high C use efficiency, highlighting a key mechanism by which mycorrhizal fungi mediate SOC formation and stability under shifting precipitation regimes.

137. 题目: Crop straw biochar enhances hydrocarbon adsorption in ground water
文章编号: N25112704
期刊: Chemosphere
作者: Abhijeet Pathy, M Anne Naeth, Scott X Chang
更新时间: 2025-11-27
摘要: Hydrocarbon fuel production and use can pose environmental risks, such as spills during extraction and transportation, which can contaminate soil, damage vegetation, adversely affect human and animal health, and contaminate ground water with soluble hydrocarbons, that could spread to surrounding areas. Our study evaluates the simultaneous adsorption capacity of canola straw biochar for 12 hydrocarbon pollutants in ground water from a northern peatland. This approach simulates the simultaneous contamination of multiple hydrocarbon classes in a complex aqueous matrix. In the laboratory, canola straw biochar remediated benzene, toluene, ethylbenzene, and xylene (BTEX), and linear chained and polycyclic aromatic hydrocarbons from ground water. BTEX concentrations significantly decreased with application of 1 g L−1 biochar, achieving a remediation efficiency of over 95 % within 7 days. Increasing application rates enhanced remediation efficiency, exceeding 99 % at a 2 g L−1 application rate. Hydrocarbon adsorption on biochar is a complex process involving surface interactions and diffusion-controlled steps, with the kinetic data fitting well to models indicative of chemisorption. X-ray photoelectron spectroscopy, BET/CO2 porosimetry and Fourier transform infrared spectroscopy corroborated theoretical isotherm and kinetic models, indicating that functional groups on the biochar surface play a crucial role in adsorption, primarily through hydrophobic and π-π interactions. The results enhanced our understanding of adsorption mechanisms for multiple hydrocarbon classes in complex matrices under controlled laboratory conditions, and positioned canola straw biochar as an effective remediation technique for hydrocarbon water treatment. Biochar is made from waste agricultural materials and sequesters carbon, contributing to environmentally sustainable remediation and a circular economy.

138. 题目: The impact of soil and water conservation configurations on soil organic carbon loss from meter-resolution imagery in the Loess Plateau, China
文章编号: N25112703
期刊: Journal of Hydrology
作者: Wangliang Ge, Jianzhao Wu, Miao Zhang, Shihe Zhang, Feng Yang, Lei Deng
更新时间: 2025-11-27
摘要: China’s Loess Plateau (CLP) has undergone substantial landscape transformation due to the widespread implementation of soil and water conservation (SWC) measures, resulting in a marked reductions in both sediment yield and soil organic carbon (SOC) loss. However, the extent to which these measures influence SOC loss remains insufficiently unexplored, limiting the transferability of these successes to other erosion-prone regions. Here, we first map the spatial distribution of the SWC measures in dam-controlled watersheds by integrating high-resolution satellite imagery, digital surface models, and Random Forest-based machine learning algorithms, achieving an average overall accuracy and F1-score of 0.94. We subsequently combine these spatial datasets with sediment yield and SOC loss records from 25 dam-controlled watersheds to investigate the impacts of SWC measure configurations on SOC loss across the watershed, slope-position, and landscape scales. We show that rainfall, topography, and vegetation exert substantial influences on SOC loss, with extreme rainfall events exhibiting particularly pronounced effects. Both vegetation-based SWC measures and terracing substantially reduce SOC loss, with terracing demonstrating maximum effectiveness at 0–40 % coverage. The effectiveness of SWC measures varied by slope position and watershed type, with mid-slope zones (15–25°) exhibiting the strongest influence on SOC loss mitigation. Moreover, the landscape configuration of SWC measures exert a notable effect on SOC loss, with higher levels of spatial fragmentation associated with greater losses. These findings advance mechanistic understanding of the role of SWC measures in SOC dynamics and provide an empirical foundation for optimizing erosion control strategies and the spatial allocation of conservation interventions in the CLP and similar erosion-ecological systems.

139. 题目: Divergent pathways of shaping soil organic carbon accumulation in a riparian wetland modulated by vegetation type and microbial‑iron coupling
文章编号: N25112702
期刊: Applied Soil Ecology
作者: Lei Zhang, Wenbo Liu, Hongying Du, Weichao Wang, Yuyang Xie, Junkang Guo, Yinping Bai, Aigang Lu, Zhiping Wang
更新时间: 2025-11-27
摘要: Although vegetation restoration with increased species diversity benefits soil organic carbon (SOC) accumulation in wetland ecosystems, however, the mechanisms involved and coupling plant-microbe-mineral interactions under different vegetation regimes and flooding gradient remain insufficiently explored. Here, 42 plots were selected in a typical Yellow River wetland with sandy soil, where the changes in microbial life history strategy, plant- and microbial-derived components, and Fe-mediated dual oxidation/mineral protection in SOC accumulation were assessed in response to different vegetation types, including an unplanted floodplain. The restoration significantly increased SOC (1.06–7.58 g kg−1), total microbial necromass C (MNC, 12.8–24.3 % of SOC) and lignin phenol contents. High-biomass woody and graminoid species, particularly Phragmites australis exhibited high bacterial and fungal K/r ratios, enhancing accumulation from lignin-derived and fungal necromass, thereby facilitating the development of mineral-associated organic carbon (MAOC, ∼66 % of SOC) for long-term stabilization. Concurrently, the negative correlation between MNC (lignin phenols) and its relative contribution to the formation of SOC highlights the MAOC formation or the accumulation of other recalcitrant compounds. In contrast, low-biomass herbaceous species favor bacterial r-strategists that accelerate particulate organic carbon (POC) turnover via heightened hydrolytic enzyme activities, while stimulating Fe(II)-derived •OH oxidation, promoting CO₂ emission and carbon pool lability. Additionally, iron in waterlogged systems couples anaerobic preservation of DOC with the highest CO₂ emissions through Fe-mediated oxidation. Our study demonstrates that plant types regulate microbial life history strategies, thereby influencing SOC dynamic and turnover, offering a clear mechanism for enhancing carbon sequestration and stability through strategic vegetation management.

140. 题目: Insights into the complex nature of dissolved organic matter from plant residues using multiple spectroscopic techniques
文章编号: N25112701
期刊: Organic Geochemistry
作者: Zongtang Yang, Biswaranjan Mohanty, Feike A Dijkstra, Georg Guggenberger, Balwant Singh
更新时间: 2025-11-27
摘要: Dissolved organic matter (DOM) is the most active and labile organic fraction in soils, participating in numerous biogeochemical processes. Comprehensive understanding of DOM composition at the molecular level remains a challenge due to limited or contrasting analytical data based on a single technique or limited analysis, which may be addressed using multiple complementary techniques. In this study, we utilized five prevalent and novel spectroscopic and spectrometric techniques, i.e., XPS, FTIR, NEXAFS, NMR, and FT-ICR-MS, coupled with multivariate analysis to decipher the complexity of DOM. We extracted DOM from four decomposed plant residues − pine, eucalyptus, pasture, and wheat. The organic carbon concentration in the DOM samples followed the order: pine > eucalyptus > wheat > pasture. Eucalyptus and pasture DOM exhibited similarities in aromatic compounds but differed in saturation and O-containing groups. Pine DOM was enriched in aromatic and carboxylic compounds, whereas wheat DOM contained more lipid and aliphatic compounds. The differences in the abundance of functional groups and compound families were attributed to the influence of both the original plant residues and microbial degradation. Chemical convergence of the four DOM samples, reflected by their broadly similar spectral composition was possibly due to similar biodegradation processes but in different stages. Multivariate analysis of multiple spectroscopic data comprehensively captured the DOM composition.