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41. 题目: Particulate and mineral-associated organic carbon exhibit contrasting long-term trajectories across photovoltaic microhabitats in arid deserts
文章编号: N26100502
期刊: Environmental Technology & Innovation
作者: Jianhua Xiao, Anlin Wang, Fenghua Sun, Daiying Yin, Guobin Kan, Jing Zhou, Xinxin Li, Chenchen He, Qinghui An, Rui Ma, Longfei Chen
更新时间: 2026-10-05
摘要: Large-scale photovoltaic (PV) deployment is expanding rapidly across arid deserts, yet the decadal responses of soil organic carbon (SOC) fractions within panel-induced microhabitats remain poorly understood. Utilizing a 14-year PV chronosequence in arid Northwest China, we tracked the spatiotemporal dynamics and drivers of particulate (POC) and mineral-associated organic carbon (MAOC) across three panel-induced microhabitats: under-panel (UP), between-panels (BP), and front-edge (FE). At the 14-year PV power station, SOC, POC, and MAOC contents were significantly higher across all three panel-induced microhabitats than in their corresponding local controls. Crucially, the accumulation rates of SOC and POC exhibited distinct temporal thresholds at different panel positions: the UP entered the rapid accumulation phase earliest, whereas the BP reached its acceleration point after approximately 7 years; conversely, and the FE decelerated after 9 years. In contrast, MAOC increased approximately linearly across the chronosequence in all three microhabitats. Within the chronosequence, operational age explained the largest proportion of POC variability, whereas MAOC variability was jointly associated with operational age, microhabitat, and their interaction. Meanwhile, POC and MAOC are also indirectly driven by the local improvements in soil moisture and nutrients induced by operational duration and panel microhabitats. These findings highlight the necessity of integrating carbon fraction dynamics and microhabitat-specific processes into assessments of long-term carbon sequestration potential within expanding dryland PV ecosystems.

42. 题目: Fixed-bed adsorption and techno-economic analysis of malic acid-activated corncob biochar within a solvent recovery system
文章编号: N26100501
期刊: Environmental Technology & Innovation
作者: Ratthakarn Jumroonrat, Nattawin Chawaloesphonsiya, Thaksina Poyai, Pharkphum Rakruam, Pisut Painmanakul
更新时间: 2026-10-05
摘要: Hydrocarbon-contaminated drill cuttings pose a critical environmental challenge due to their complex composition and high loading of persistent organic pollutants. This study evaluates the application of previously developed malic acid-activated corncob biochar (MCB) for a fixed-bed solvent recovery process. MCB exhibited outstanding removal of total petroleum hydrocarbons (TPH) from ethyl lactate, achieving the maximum adsorption capacity of 132.66 mg g⁻¹ , prolonged breakthrough time, and superior bed utilization compared with commercial powdered activated carbon (PAC). Thermal regeneration demonstrated excellent MCB recyclability, with regeneration efficiency exceeding 90% over multiple cycles. Based on techno-economic evaluation, the laboratory-scale production cost of MCB was relatively high (149.25 USD kg⁻¹), but it became more economical under industrial-scale production (3.21 USD kg⁻¹). The industrial-scale scenario achieved an estimated ROI of 74.24% with a payback period of approximately 1.35 years. The integration of biomass valorization, adsorption, regeneration, and refuse-derived fuel (RDF) production establishes an integrated solvent recovery system with resource recovery, in which agricultural residues are transformed into adsorbents, utilized for pollutant removal, regenerated for reuse, and ultimately converted into energy resources.

43. 题目: 10-year trends of particle size distributions and equivalent black carbon at the Environmental-Climate Observatory (ECO) in Lecce (Italy)
文章编号: N26100416
期刊: Environmental Pollution
作者: Daniele Contini, Daniela Cesari, Marianna Conte, Adelaide Dinoi
更新时间: 2026-10-04
摘要: This study investigates the long-term (2015–2024) inter-annual and seasonal trends of PM2.5, coarse particles (PM10-2.5), particle number size distribution (PNSD, 10–10,000 nm), and equivalent black carbon (eBC) at the ECO Observatory in Lecce (Southern Italy) measured with online instruments. Organic (OC) and elemental (EC) carbon were analysed offline to evaluate the Mass Absorption Cross-section (MAC). Results showed a clear decoupling between fine and coarse mass fractions. PM2.5 decreased significantly by −2.58% yr−1, consistent with a reduction of local anthropogenic combustion sources. Conversely, PM10-2.5 remained stable due to the strong influence of natural Saharan dust events, which impacted 13.2% of the monitored days and induced opposite seasonal patterns between the two size fractions. eBC concentrations exhibited a statistically significant decline of −3.17% yr−1, consistent with European urban background trends. The mass absorption cross-section remained stable (12.4 ± 2.4 m2g-1). The reduction of absorption and a stable MAC suggest that the decrease of absorption is due to a decrease of eBC consistent with a decrease of combustion emissions. Seasonally, the eBC/PM10 ratio increases from 2.8% in summer to 4.2% in winter, tracking PM2.5 variations and highlighting the impact of wintertime emissions and boundary layer dynamics. Total particle number concentration (PNC) decreased by −2.99% yr−1, primarily driven by reductions in the Aitken and accumulation modes. While submicron particles peaked in winter due to combustion, the coarse mode peaked in summer due to dust. The nucleation mode lacked inter-annual seasonality because summer nucleation countered winter traffic inputs. Diurnal variations were governed by boundary layer dynamics, except for the nucleation mode, which peaked midday due to photochemical new particle formation events happening, on average, in 25% of the days.

44. 题目: Microbial necromass and aggregate structure jointly regulate divergent SOC sequestration pathways under straw return practices
文章编号: N26100415
期刊: Soil and Tillage Research
作者: Haoyang Han, Miao Wang, Lixia Liu, Yingle Liu, Zheming Liang, Peng Wu, Jiancan Liu, Ju Bai, Shanchao Yue, Yongliang Wang, Zhiping Yang
更新时间: 2026-10-04
摘要: Straw return enhances soil organic carbon (SOC) sequestration, but different practices may regulate C accumulation and stabilization through distinct pathways. A 2014 field experiment on the Loess Plateau compared conventional fertilization (CF), straw return (SR), and straw return with plastic film mulching (SRM) using SOC fractions (2016–2025), microbial necromass and enzyme activities (2016, 2019, and 2025), and aggregate characteristics (2024–2025). From 2016–2025, SOC under SR increased by 30.97%, with an early rate of 0.29 g kg−1 yr−1 and a breakpoint around the 8th experimental year. SRM showed a faster early rate of 0.39 g kg−1 yr−1 but increased SOC by 22.92% and approached an apparent equilibrium around the 6th experimental year. POC accumulated faster under SR than SRM (0.28 vs. 0.15 g kg−1 yr−1), whereas MAOC increased mainly after 2018 under SR but before 2019 under SRM, by 18.87% and 15.48%, respectively. PLS-PM identified significant positive paths from bacterial necromass carbon (BNC) to POC under SR and SRM, whereas MAOC was associated with fungal necromass carbon under SR and with BNC under SRM. SR increased aggregate stability by approximately 50.36%, and SOC retention was mainly associated with the increased proportion of > 2 mm macroaggregates. By contrast, SRM increased aggregate stability by 23.02%, while its SOC increase was associated with the > 2 mm macroaggregate proportion and C concentrations in < 0.25 mm fractions. Overall, SR may be more suitable for sustained SOC improvement, whereas SRM favors faster early accumulation but approaches apparent equilibrium earlier.

45. 题目: Explainable Machine Learning-Driven Targeted Modification of Biochar and Its Remediation Performance for Saline-Alkaline Soil
文章编号: N26100414
期刊: Environmental Research
作者: Panpan Yao, Tianhao Chen, Wenjing Liu, Ziliang Guo
更新时间: 2026-10-04
摘要: Biochar is a low-cost, eco-friendly candidate for saline-alkali soil remediation. Its practical efficacy, however, is constrained by high alkalinity, an underdeveloped pore structure, and limited surface functional sites, all of which conventional modification methods have yet to adequately address. To bridge this gap, this study developed an explainable machine learning prediction system that integrates multi-source data spanning biochar preparation parameters, physicochemical properties, and remediation outcomes, thereby enabling the reverse design of modification processes for enhanced efficacy. From the SHAP feature-importance and dependence results, the recommended ranges for the key modification parameters were derived as follows: pyrolysis temperature=600–800 °C, particle size=10–70 mesh, specific surface area (SSA)=58–698 m2/g, electrical conductivity (EC)=349–3554 μS/cm, cation exchange capacity (CEC)=80–273 cmol/kg, pH=1.76–7.8, O/C ratio=0.36–0.56, and an addition ratio =2%–10%. The feature importance ranking was: EC > pH > SSA > CEC > particle size > O/C ratio > addition ratio > pyrolysis temperature. Based on the above results, this study proposed a phosphoric acid-chitosan composite modification process. The modified biochar exhibited an enriched pore structure (SSA = 21 m2/g), abundant oxygen-containing functional groups (O/C = 0.31), and low EC (625 μS/cm). Although its SSA and O/C ratio fell outside the recommended ranges, its EC was within the ideal range. Within 14 days, it reduced the saline-alkali soil pH from 10.26 to 9.28, whereas soil treated with unmodified biochar maintained a pH of approximately 10.2. This confirms EC as a core indicator and validates the reliability and practical applicability of machine learning-optimized preparation.

46. 题目: Depth-dependent patterns of soil organic carbon fractions in Sphagnum and herbaceous wetlands
文章编号: N26100413
期刊: Geoderma
作者: Wen Tian, Changchun Song, Jiantao Xue, Hao Zhang, Yanyu Song, Wenwen Tan, Xing Xiang, Han Liu, Huan Yang
更新时间: 2026-10-04
摘要: Wetlands are global hotspots for soil organic carbon (SOC) storage, comprising particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) fractions. However, these two SOC fractions are not typically considered along soil depth when assessing SOC persistence in wetland systems. Here, based on soil sampling at two depths (surface: 0–10 cm; subsurface: 20–30 cm) across three representative wetlands spanning subtropical, mid-temperate, and cold temperate regions, including Sphagnum- and herbaceous-dominated wetland systems, the distribution of SOC fractions was delineated, alongside soil properties and microbial characteristics. Results showed that Sphagnum wetlands stored more SOC in the POC fraction, with a higher surface soil POC/MAOC ratio relative to subsurface soils. By contrast, SOC in herbaceous wetlands was dominated by MAOC, with a lower surface soil POC/MAOC ratio than in subsurface soils. The POC/MAOC ratio was positively correlated with the ratio of particulate nitrogen to mineral-associated nitrogen in both two horizons. C/N imbalance destabilized surface SOC, whereas microbial diversity and abundance promoted subsurface SOC stabilization. Bacterial and fungal carbon pump efficacies emerged as dominant controls on POC/MAOC ratios in surface and subsurface soils, respectively. Collectively, these findings illuminated divergences of SOC functionality and potential persistence between surface and subsurface soils in Sphagnum- and herbaceous-dominated wetlands, with implications for SOC dynamics under anthropogenic perturbations and climatic stress.

47. 题目: Iron-bound organic carbon responses to land-use change vary with soil carbon availability and Fe-pool composition
文章编号: N26100412
期刊: Geoderma
作者: Yanping Wu, Jinying Xu, Zhengjun Jian, Hailin You, Zheren Yan, Jiafei Ye, Wenjing Yang, Yong Ge, Bo Yao, Qiwu Hu
更新时间: 2026-10-04
摘要: Iron-bound organic carbon (Fe-OC) contributes to soil organic carbon (SOC) persistence, but its broad-scale response to land-use change (LUC) remains unclear. We synthesized paired-site observations from 75 publications worldwide. Degradation and restoration were analyzed separately relative to their respective paired reference sites. Degraded soils contained less SOC, Fe-OC, clay, total nitrogen, and total Fe, but had higher topsoil bulk density and pH. They also showed smaller relative contributions of short-range-order and organically complexed Fe forms. Restored soils contained more SOC, Fe-OC, clay, nutrients, and total Fe and showed greater relative contributions of these Fe forms, but had lower pH. However, Fe-OC accounted for a smaller share of SOC in restored soils, while organic carbon loading relative to extractable Fe was higher. Predictor support differed between LUC categories: SOC, pH, and microbial biomass carbon (MBC) received the strongest statistical support under degradation, whereas SOC, C/N, and the Feo/Fed ratio received the strongest support under restoration. Overall, these independent contrasts indicate that Fe-OC responses vary with soil carbon availability and Fe-pool composition. Higher bulk SOC in restoration comparisons therefore does not necessarily indicate a proportionally greater contribution of Fe-associated carbon.

48. 题目: Effect of hydrogen bonding on the humification of humic precursors with Fe-Mn concomitant minerals
文章编号: N26100411
期刊: Journal of Environmental Chemical Engineering
作者: Zhiwei Zhang, Xiang Li, Chenghong Ao, Yan Xie, Duowen Yan, Xinchen Shang, Shakeel Ahmad, Danping Wu, Xinwei Dong, Bo Pan
更新时间: 2026-10-04
摘要: In nature settings, iron minerals usually coexist with manganese in an isomorphous-replacement manner, attributable to the equal ionic radii of ferric iron and trivalent manganese. Nevertheless, it remains unclear whether abundant surface hydroxyl groups on manganese-substituted iron minerals influence humification. Herein, the abiotic humification of humic precursors with manganese-substituted iron mineral (e.g. Mn-substituted goethite) was systematically investigated for the first time, especially in the role of hydrogen bonding interactions between the mineral and humic precursors. Mn-substituted goethite possessed a greater surface hydroxyl density compared to pure goethite, resulting in a significantly accelerated humification rate. Furthermore, the introduction of a hydrogen bonding shielding agent, such as dimethyl sulfoxide (DMSO), into the reaction system containing humic precursors and the mineral resulted in a marked decrease in both the manganese concentration within the precursor solution and the system’s overall electron transfer capability. These results demonstrated that hydrogen bonding between the mineral and humic precursors enhanced their electron transfer rate, thereby facilitating the humification process. This research offers new insights into abiotic humification mediated by iron/manganese concomitant minerals, enriching the understanding of the global carbon cycle affected by soil geochemical processes.

49. 题目: Feedstock-Derived Biochar Heterogeneity Regulates Ammonia Volatilization and Soil Nitrogen Dynamics in AWD Paddies
文章编号: N26100410
期刊: Environmental Technology & Innovation
作者: Yihao Hu, Yalong Li, Wanting Zhang, Yujiang Xiong, Yuan Qiu, Linlin Fan, Hongwei Han, Feng Zhang, Taotao Chen
更新时间: 2026-10-04
摘要: Agri-forestry residue biochar boosts soil inorganic nitrogen (N) availability and cuts N loss for better agricultural N management. However, biochars derived from different feedstocks can exert contrasting effects on NH3 volatilization, while their multi year responses under alternate wetting and drying (AWD) irrigation and the relationships between biochar physicochemical properties and soil N dynamics remain poorly understood. A 3-year field trial was carried out under AWD conditions, including four treatments: no biochar application (B0), maize straw biochar at 20 t·ha−1 (BMS), rice husk biochar at 20 t·ha−1 (BRH), and sawdust biochar at 20 t·ha−1 (BSD). The results showed that compared with B0, BRH consistently mitigated cumulative NH3 volatilization by 7.30%-22.68% across 3-year, while BMS and BSD increased emissions by 35.85%-38.54% in the first year, then decreasing it by 9.96-13.94% and 12.04-15.72% in the subsequent two years, respectively. BRH also exhibited the strongest enhancement on soil inorganic N, significantly increasing soil NH4+-N by 28.89-52.74% throughout the 3-year experimental period, while a significant increase in soil NO3−-N (35.40%) was observed only in 2022. The superior performance of BRH from its mild pH (8.23), the highest specific surface area (107.56 m2·g−1) and ID/IG ratio of BRH was 0.77 which was 10.00-14.93% higher than that of BMS and BSD. Therefore, biochar physicochemical properties, governed by feedstock type, are critical determinants of NH3 volatilization and soil inorganic nitrogen dynamics under AWD. Among the tested biochar, BRH is the most effective option for enhancing soil nitrogen retention and reducing NH3 volatilization.

50. 题目: Controlled transition from hydrothermal carbonization to fulvification for artificial humic substance production from wheat straw
文章编号: N26100409
期刊: Chemical Engineering Journal
作者: Opeyemi Ayodeji Akogun, Giulia Ischia, Mohaddeseh Mohammadebrahimi, Fabiano Bisinella Scheufele, Silvia Román, Nicole D Berge, Luca Fiori, Judy A Libra, Vera Susanne Rotter, Thomas Hoffmann, Nader Marzban
更新时间: 2026-10-04
摘要: This study presents a controlled hydrothermal pathway for valorizing wheat straw through carbonization (HTC), humification (HTH), and fulvification (HTF) by systematically varying temperature and alkalinity. Increasing alkalinity and temperature promoted depolymerization and solubilization of lignocellulosic structures, enabling a continuous transition from solid-dominated to liquid-dominated product regimes. HTC produced the highest solid yield (67.5%) and carbon recovery (77.9%), but generated high levels of furfural and 5-hydroxymethylfurfural (HMF). Compared with HTC, HTH and HTF strongly suppressed furanic and phenolic compounds, with furfural and HMF reduced to 70% in solids and >90% in liquids. HTF reduced solid yield to 3.3% while maximizing the solubility of lactic acid (37.5 g/L) and formic acid (14.6 g/L). At 180 °C, HTF yielded substantially higher liquid-phase total organic carbon (TOC) of 50.66 g/L than HTC (16.03 g/L) and HTH (42.51 g/L). Within HTF, increasing temperature from 180 to 220 °C further enhanced carbon solubilization, with liquid-phase TOC increasing by ~32% to 66.84 g/L, indicating intensified conversion of lignocellulosic carbon into soluble organic products, in contrast to HTC and HTH, where increasing temperature led to a decrease in liquid-phase carbon content. Spectroscopic and thermal analyses showed humic- and fulvic-like structures with enhanced thermal stability at higher alkalinity. These findings show that process tuning enables targeted biomass conversion into energy-rich hydrochar via conventional HTC or more homogeneous, nutrient- and carbon-rich liquid products via HTF, opening new opportunities for agriculture and liquid-phase biorefinery research.

51. 题目: Coffee ground biochar enhances the purification of agricultural runoff in constructed wetlands: Responses and mechanisms at the plant, substrate, and microbial levels
文章编号: N26100408
期刊: Chemical Engineering Journal
作者: Yuansong Tian, Jingchang Zhang, Jimeng Feng, Jian Shen, Xinze Wang
更新时间: 2026-10-04
摘要: Constructed wetlands (CWs) remain insufficient for mitigating agricultural non-point source pollution caused by pesticide-laden runoff and mismanaged agro-industrial byproducts. While biochar is a widely established amendment, the efficiency and underlying mechanisms of a “waste-treats-waste” strategy—using agro-industrial byproduct-derived biochar to boost CW performance in treating pesticide-laden agricultural runoff—are still insufficiently elucidated. This study prepared spent coffee ground (SCG) biochar at varying pyrolysis temperatures (400–800 °C) as functional amendments for CWs. Their performance and mechanisms in treating atrazine (ATZ)-contaminated farmland drainage were systematically evaluated. The results demonstrated that the CW-800 system achieved significantly higher ATZ removal efficiencies (75.63–100%) compared with the control (2.68–20.48%), while concurrently boosting COD, nitrogen, and phosphorus removal. Furthermore, biochar amendment promoted wetland plant biomass, elevated soluble protein content, and optimized antioxidant enzyme activities. Substrate characterization and adsorption experiments revealed that the high specific surface area and well-developed microporous structure of high-temperature biochar facilitated ATZ removal via adsorption. Concurrently, substrate enzyme activity assays indicated that biochar supplementation boosted key enzyme activities involved in organic load degradation and nutrient removal. Microbial community analysis showed that biochar increased community evenness and diversity under high-load conditions without significantly altering richness, while simultaneously enriching potentially degrading taxa including Patescibacteria, Pseudomonadota, and Thermodesulfobacteriota. Integrated LC-MS and qPCR analyses revealed that key functional genes (atzA and trzN) drive dechlorination and hydrolysis pathways, thereby attenuating ATZ ecotoxicity. Overall, this study offers crucial theoretical insights that support the resource utilization of agro-industrial byproducts and advance the application of CWs for agricultural drainage remediation.

52. 题目: Adsorption performance and mechanism of nitrofurazone on iron-nitrogen co-doped biochar derived from waste sugarcane bagasse
文章编号: N26100407
期刊: Journal of Environmental Chemical Engineering
作者: Haijun Tan, Zucheng Wu, Lu Wang, Jun Liu, Xi Chen, Zongfeng Pu, Boguang Niu, Peipei Zhang
更新时间: 2026-10-04
摘要: The widespread contamination of water bodies by nitrofurazone (NFZ) poses a serious threat to ecosystems and human health; however, studies on its efficient adsorptive removal remain limited. In this study, iron–nitrogen co-doped biochar (FeNHC) was prepared from sugarcane bagasse using ferric nitrate and urea as modifiers through hydrothermal pretreatment coupled with high-temperature pyrolysis. Magnetic Fe₃O₄ was generated in situ during pyrolysis, enabling rapid solid–liquid separation under an external magnetic field. The iron leaching concentration was below 0.01 mg·L⁻¹ (pH = 6.6, 120 min), indicating satisfactory chemical stability. FeNHC exhibited a maximum adsorption capacity of 113.6 mg·g⁻¹ toward NFZ, and the adsorption process was well described by the Langmuir isotherm model. Based on XPS, FTIR, and DFT calculations, the adsorption mechanism was proposed to involve the synergistic effects of pore filling, hydrogen bonding, π–π interactions, and surface complexation. Under a wide pH range, in the presence of coexisting ions and humic acid, and in real water matrices, FeNHC maintained a removal efficiency above 70% for NFZ and exhibited good reusability. This study provides a green and recoverable adsorbent for the valorization of waste biomass and the remediation of NFZ-contaminated water, and also offers a reference for biochar functionalization strategies.

53. 题目: Effects of novel stover valorization pathways on soil organic matter dynamics in a highly weathered soil
文章编号: N26100406
期刊: Geoderma
作者: E Sonntag, A Parodi, G Rahmann, J W van Groenigen, A Vidal
更新时间: 2026-10-04
摘要: Soil organic matter (SOM) is vital for soil health and productivity in the highly weathered soils of Sub-Saharan Africa, where crop residue management is crucial for replenishing SOM. Novel circular stover valorization pathways for stover, including oyster mushroom cultivation and vermiculture, can enhance food security while returning organic amendments to soil. However, from an equivalent amount of maize stover, these pathways generate amendments varying in carbon quantity and quality due to differing conversion efficiencies and losses, and their effects on soil carbon relative to conventional stover management remain unclear. We evaluated five maize stover-derived amendments in a 51-day incubation of a highly weathered soil: stover, burned stover, spent mushroom substrate (SMS), vermicomposted stover (VCstover), and vermicomposted SMS (VCSMS), applied at rates reflecting each pathway’s biophysical potential. Novel pathways produced amendments with roughly one-third to one-half the carbon content of stover and lower C/N ratios (43–63 vs. 94). All amendments except burned stover significantly increased heterotrophic respiration. Despite contrasting carbon inputs, bulk soil carbon after 51 days remained unchanged across all novel amendments relative to the control. However, vermicomposted amendments (VCSMS and VCstover) shifted SOM partitioning toward particulate (POM) and away from mineral-associated organic matter (MAOM), with POM rising from 43 % to 51–53 %. This suggests that the vermicomposting pathway could influence early SOM formation, reflecting the combined effects of amendment processing and lower C inputs rather than either alone. Although observed over 51 days, this effect could carry longer-term implications for carbon persistence given MAOM’s greater stability. In the short-term, novel stover valorization pathways show potential to maintain soil carbon while supporting food security.

54. 题目: Effects and mechanisms of sustained-release embedded composite biochar in carbon enhancement and acid reduction of acidified black soil
文章编号: N26100405
期刊: Journal of Environmental Management
作者: Yali Sun, Wenxin He, Guangxuan Yin, Junhao Wan, Ciming Yi, Jian Ke, Weitao Shen, Mingshuang Zhang, Ruixin Guo, Yanhua Liu, Jingge Shang, Jianqiu Chen, Qianjiahua Liao
更新时间: 2026-10-04
摘要: Black soils in Northeast China are undergoing acidification and organic matter degradation, and are in urgent need of efficient and environmentally sustainable improvement technologies. In this study, a novel sustained-release embedded composite biochar material was fabricated through a ball-milling integration process, in which biochar, reduced iron powder, and polymer materials were combined. A systematic screening process was established through the optimization of biochar substrate preparation conditions, the selection of functional loading components, and the development of a sustained-release carrier process. Through physicochemical characterization and evaluation of environmental effects, Chitosan-Fe-Biochar(CS-Fe-BC) and Polyacrylamide-Fe-Biochar(PAM-Fe-BC) were ultimately identified as the optimal materials. A 180-day incubation experiment was conducted under simulated climate conditions representative of Northeast China. Within 180 days, the application of 5‰ CS-Fe-BC[5] increased soil pH by approximately 0.5 units and enhanced SOC content by about 26.88%.The application of different material treatments effectively improved the structural integrity of the soil carbon pool, leading to significant increases in POC, ROC, andMOC contents. The metagenomic sequencing results revealed that, while maintaining overall abundance stability, the composite material reshaped the soil microbial community structure, facilitated the enrichment of functional bacteria involved in carbon fixation and acid mitigation, and achieved carbon enhancement and acid reduction through differentiated metabolic pathways. These findings suggest that the material plays a pivotal role in driving the processes of carbon accumulation and acid mitigation.The research findings may offer novel materialand theoretical support for the sustainable management of black soil acidification in Northeast China.

55. 题目: Molecular associations between dissolved organic matter restructuring and anammox-derived nitrate reduction in pilot-scale mature landfill leachate treatment
文章编号: N26100404
期刊: Chemical Engineering Journal
作者: Mi Lin, Bifeng Zhang, Yunyun Li, Huilin Gan, Jingjing Wang, Junxing Liu, Yonggan Li, Zhenguo Chen, Xiaojun Wang
更新时间: 2026-10-04
摘要: Mature landfill leachate contains high ammonium and refractory dissolved organic matter (DOM), making deep nitrogen removal challenging. Although anammox-based processes have been widely applied to mature landfill leachate treatment, their high total nitrogen removal often exceeds what can be explained by anammox stoichiometry alone. The molecular basis of this ‘beyond-anammox’ nitrogen removal remains unclear. In this study, a pilot-scale integrated partial nitritation–denitrification–PN/A (PN–DN–PN/A) system treating mature landfill leachate was investigated by integrating water quality monitoring, DOM molecular characterization, microbial functional prediction, paired mass distance analysis, and DOM–function association networks. The system achieved stable NH4+–N and total inorganic nitrogen removal efficiencies of 94.54 ± 0.47% and 93.97 ± 0.28%, respectively. Observed NO3−–N in the PN/A effluent was only approximately 3.95% of the anammox-stoichiometric prediction, suggesting additional nitrate-consuming processes. DOM was selectively restructured along the treatment train, with depletion of protein- and lipid-like molecules and enrichment of lignin-, tannin-, and condensed aromatic-like components. Higher oxygenation, unsaturation, aromaticity, and carbon oxidation state indicated preferential removal or transformation of reduced DOM with higher electron-donating potential. Microbial functional prediction and DOM–function association networks further linked PN/A-depleted DOM molecules with heterotrophic carbon metabolism, nitrate reduction, denitrification, and anammox-related functional potentials. These results suggested that upstream DOM restructuring may contribute to an endogenous electron-donor pool associated with the reduction of anammox-derived nitrate in the PN/A reactor. This DOM-quality perspective provides a molecular basis for optimizing low-carbon PN/A treatment of mature landfill leachate.

56. 题目: Influence of pore structure and nitrogen-containing functional groups on the competitive adsorption of high-pressure CO2/H2 by biochar
文章编号: N26100403
期刊: Separation and Purification Technology
作者: Hong Tian, Jiwen Fu, Lei Liu, Hongyu Chen, Zheng Zeng, Sijin Chen, Fubin Ma
更新时间: 2026-10-04
摘要: In steam methane reforming (SMR) for hydrogen production, efficient CO2 removal is essential. Although ultra-micropores and nitrogen doping enhance CO2 adsorption on carbon adsorbents, their combined effects under high-pressure conditions remain unclear. Herein, a nitrogen-doped biochar (NC), an activated biochar (AC), and a nitrogen-doped activated carbon (NC-AC) were prepared from waste coconut shell. AC exhibited a highly developed pore structure (specific surface area of 1547 m2/g and micropore volume of 0.644 cm3/g), whereas NC was rich in nitrogen content (16.49 wt%). NC-AC combined a moderate nitrogen content (3.06 wt%) with an abundant porous network. High-pressure CO2 adsorption isotherms revealed a pressure-dependent evolution in the relative contributions of nitrogen-containing functional groups and pore structure: the contribution of nitrogen-containing functional groups was more pronounced at low pressures (2 bar). Dynamic column breakthrough experiments with a CO2/H2 mixture (20/80 vol%) demonstrated that NC-AC exhibited the highest CO2 uptake. Molecular simulations showed that at low pressure, the 0.6 nm pore exhibited the highest CO2 adsorption, while at 10 bar, the 0.8 nm pore surpassed due to its strong interaction forces and large packing space. In the 0.8–1.0 nm pores, CO2 preferentially formed multilayer adsorption near the pore walls and pushed H2 toward the pore center. Among nitrogen-functional groups, pyrrolic N (N-5) significantly enhanced the CO2 adsorption capacity and selectivity.

57. 题目: Modeling microbial regulatory feedback in organic matter decomposition identifies copiotrophic traits as key drivers of positive priming
文章编号: N26100402
期刊: Biogeosciences
作者: Firnaaz Ahamed, James C Stegen, Emily B Graham, Timothy D Scheibe, Hyun-Seob Song
更新时间: 2026-10-04
摘要: . Microbial decomposition of complex soil organic matter (OM) is often regulated by labile organic carbon inputs, a phenomenon known as priming, which plays a critical role in belowground biogeochemical cycling. However, the strength and direction of microbial priming of soil OM pools varies significantly across ecosystems. A generalizable mechanistic framework explaining the factors that lead to accelerated (positive priming) or impeded (negative priming) rates of OM decomposition is still lacking. In this work, we conceptualize priming as a microbial feedback loop that optimizes the costs and benefits of maximizing growth rate, specifically, the cost of exoenzyme synthesis for decomposing complex OM versus the benefit of energy acquisition from labile OM. We examined the impacts of microbial functional traits and interactions on priming by employing a cybernetic modelling approach, which predicts complex microbial growth patterns by accounting for dynamic metabolic regulations. We simulated microbial priming across ecological community configurations composed of degraders and non-degraders with either oligotrophic or copiotrophic traits, resulting in seven combinations that included both single functional groups (degraders with either trophic trait) and binary functional groups (combinations of degraders and non-degraders, or degraders only, with differing or common trophic traits). Configurations with only non-degraders were excluded, as they are irrelevant for studying priming in OM decomposition. Monte Carlo simulations for these scenarios revealed: (1) positive priming is prevalent, while negative priming occurs sporadically under specific parameter settings; (2) positive priming is more frequently observed in microbial systems with copiotrophic degraders than those with oligotrophic degraders; (3) the presence of copiotrophic non-degraders suppresses positive priming, whereas the presence of oligotrophic non-degraders promotes it; and (4) the temporal dynamics of priming is also influenced by microbial functional traits and interactions. These findings highlight the driving role of microbial functional traits and interactions in priming. Notably, copiotrophic degraders inducing strong positive priming is consistent with microbial energy mining through enhanced degradation of complex OM, whereas suppression of positive priming under copiotrophic non-degraders suggests reduced use of labile OM for co-metabolism and complex OM-degrading enzyme production. Most strikingly, our simulations predicted a dramatic positive priming effect triggered by the addition of a small amount of labile OM (i.e., specifically less than 10 % of the total OM in the complex and labile OM mixture in this study), with no notable changes observed beyond this point. This indicates that microbial regulatory feedback operates nonlinearly, possibly reflecting saturation of microbial demand for energy. As we used a generalized microbial model, we hypothesize that our findings may reflect common features of OM priming across diverse microbial systems and environments. Overall, this work, combining new theories and models, significantly enhances our understanding of priming by providing model-generated and empirically testable hypotheses on the mechanisms governing it.

58. 题目: Vertical carbon and biochar transport in a sandy soil lysimeter experiment
文章编号: N26100401
期刊: Geoderma
作者: Arthur Gross, Jens Kruse, Nina Siebers, Bruno Glaser, Snežana Maletić, Marijana Kragulj Isakovski, Slaven Tenodi, Lutz Weihermüller
更新时间: 2026-10-04
摘要: Sandy soils are characterized by high water infiltration, low water and nutrient retention, and low soil organic matter (SOM). Organic soil amendments (OSA) can improve hydraulic properties and SOM levels, making them suitable for sustainable agricultural use. Additionally, biochar amendments sequester atmospheric carbon dioxide and interact with SOM, potentially enhancing its stability. This study analyzed carbon dynamics in a sandy soil following the addition of OSA, including dredged sediment (20 %) and compost (5 %), mixed with and without biochar (1 %). For this purpose, a lysimeter experiment was setup in Novi Sad, Serbia, and conducted for 441 days. Total organic carbon (TOC) stocks in the lysimeters were measured after the experiment and compared with the amounts of TOC added at the beginning. Drained water amounts were collected throughout the experiment and analyzed for truly dissolved organic carbon (DOC) and particulate organic carbon (POC) in the first six months. Black carbon was used to specifically analyze biochar in 5 cm increments of the lysimeter columns at the end of the experiment. This molecular marker revealed no significant vertical biochar transport but accumulation trends in intermediate lysimeter levels. The addition of compost exhibited the highest relative TOC loss with 24.5 %, although differences were not statistically significant. DOC leaching with increased by 0.17 % (p < 0.05) if compost was added purely. Mixing compost with biochar did not affect the TOC loss but significantly reduced DOC leaching. Sediment additions led to the highest relative POC loss with 0.023 % but were significantly mitigated (p < 0.05) by co-additions of biochar. Combining both OSA with biochar was associated with lower DOC and POC leaching than adding sediment and compost alone, while the relative TOC loss was not significantly affected. These findings suggest that biochar influences the partitioning and leaching of organic carbon in coarse-textured soil agroecosystems.

59. 题目: Dissolved organic matter addition alters diel nitrogen and phosphorus uptake downstream of a wastewater treatment plant effluent
文章编号: N26100310
期刊: Biogeochemistry
作者: David Pineda-Morante, Miquel Ribot, Susana Bernal, Anna Lupon, Sara Castelar, Esperança Gacia, Stephanie N Merbt, Francesc Sabater, Helena Guasch, Eugènia Martí
更新时间: 2026-10-03
摘要: Wastewater treatment plant (WWTP) effluents deliver high loads of dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) to receiving streams and can generate dissolved organic carbon (DOC): nutrient imbalances, potentially constraining microbial DIN and SRP processing and increasing downstream nutrient export. We hypothesized that increasing bioavailable DOC supply and altering DOC: nutrient stoichiometry would stimulate heterotrophic activity and enhance in-stream DIN and SRP uptake downstream of a WWTP effluent. We conducted a four-day reach-scale enrichment with a brewery-derived dissolved organic matter (DOM) solution rich in bioavailable DOC in a Mediterranean headwater stream fed exclusively by WWTP effluent. Hourly samples were collected upstream and at two downstream stations relative to the DOM injection point to quantify spatiotemporal variation in net nutrient uptake. Stoichiometric analysis suggested that heterotrophic nutrient uptake was constrained by DOC and DIN relative to high SRP availability. DOM enrichment partly alleviated DOC limitation, and rapid net DOC removal occurred within the first meters downstream of the injection point, coinciding with strong oxygen depletion and benthic mat development. During enrichment, the reach shifted from net DIN source to sink, mainly through enhanced nitrate uptake. Ammonium uptake showed a weaker, more localized, and diel-dependent response, whereas no clear effect was detected for SRP uptake. Despite enhanced local uptake, whole-reach reductions in DIN and SRP export remained < 15% relative to WWTP nutrient loads. Overall, our results support using system-specific C:N:P stoichiometry to guide DOC-based nutrient attenuation strategies by identifying C, N, and P limitation or excess in WWTP-receiving streams.

60. 题目: Litter nitrogen drives soil organic carbon sequestration by promoting microbial residue carbon accumulation
文章编号: N26100309
期刊: Plant and Soil
作者: Min Zhang, Han Li, Yanmeng Wang, Yongxing Cui, Yi Gao, Yanlong Jia, Hongwei Yu, Qinglong Dong, Ying Wang, Zhongqi Xu
更新时间: 2026-10-03
摘要: Aims Microbial residue carbon (MRC) plays a critical role in soil organic carbon (SOC) sequestration and stability. Yet, its accumulation depends on litter inputs, and the role of litter quality in regulating MRC remains unclear. Methods We assessed litter quality, SOC content and fractions, as well as amino-sugar and lignin-phenol contents in broadleaved, coniferous, and mixed forests, and evaluated microbial nutrient limitations using an ecological stoichiometric approach. Results We found that lignin content, and C lability were lowest in the broadleaved forest, while litter N, P, and cellulose content, the N/Lignin ratio, SOC content, and the microbial N limitation were highest. Soil MRC, bacterial residue carbon (BRC), and fungal residue carbon (FRC), lignin phenols, and the degree of lignin degradation were also highest in the broadleaved forest. Microbial and plant residue C accumulated synchronously with SOC across the different stand types. Random forest analysis indicated that litter N was the primary factor driving the accumulation of MRC. Structural equation modeling revealed that higher litter N intensified the microbial N limitation, which promoted MRC accumulation. The accumulation of MRC, especially BRC, increased ROC content, thereby reducing the C lability of the overall SOC. Conclusions Changes in stand type lead to shifts in litter N, which primarily regulate SOC sequestration through the microbial C pump. The input of N-rich broadleaved stimulated microbial growth, increased the accumulation of MRC, particularly BRC, enhanced ROC content, and consequently improved SOC stability.