论文检索

总访问量：5360576次

总访客量：313709人

所有论文

41. 题目: Macadamia nutshell-derived N-doped biochar supported Co-Fe/CoFe2O4 with strong electronic coupling for enhanced peroxymonosulfate activation and 2,4-dichlorophenol degradation
文章编号: N26061006
期刊: Separation and Purification Technology
作者: Nguyen Lan Thanh, Nguyen Nhat Huy, Phan Thi Thuy, Le Viet Ngan, Ta Cong Khiem, Kun-Yi Andrew Lin, Vu Dinh Thao, Le The Son, Tran Viet Thu, Tran Tien Dat, Nguyen Trung Dung
更新时间: 2026-06-10
摘要: In this study, a magnetic N-doped macadamia nutshell biochar-supported Co-Fe/CoFe2O4 catalyst (CF@NBCM) was synthesized from agricultural waste-derived biochar and Co/Fe-MIL-101-NH2 and applied for the degradation of 2,4-dichlorophenol (2,4-DCP) in aqueous solutions via peroxymonosulfate (PMS) activation, achieving removal efficiencies of 77.10–96.83%. The high degradation efficiency of 93.03% and mineralization efficiency of 63.25% within 40 min is due to the synergistic effect among the accelerated electron mediator NBCM and Co and Fe species in the CF@NBCM/PMS system. Radical quenching experiments, electron paramagnetic resonance analysis, and electrochemical analysis indicate that both radical (SO4•-) and nonradical (1O2 and direct electron transfer) pathways are involved in 2,4-DCP degradation in the CF@NBCM/PMS system. The primary active species were identified as Co0/Co2+/Co3+ and Fe0/Fe2+/Fe3+, while pyridinic N and graphitic N significantly enhanced the catalytic performance. Furthermore, N doping modulated the electronic structure of adjacent carbon atoms and activated delocalized π electrons on the biochar surface, creating robust anchoring sites that facilitated efficient electron transfer between Co and Fe atomic sites. The high stability of the catalyst was attributed to the synergistic effects of N incorporation and the encapsulation of metal particles within an N-doped carbon layer, which prevented direct contact between the metals and strong acidic or oxidative environments. In addition, mass spectrometry combined with density functional theory calculations was employed to identify the degradation intermediates of 2,4-DCP and to assess the toxicity of its degradation products. This study provides a novel strategy for designing highly efficient bimetal and N-doped carbon composite materials for the degradation of organic pollutants in water.

42. 题目: Regional diversity in black carbon emissions, size, and mixing state Across Asia: Implications for climate and public health
文章编号: N26061005
期刊: Earth-Science Reviews
作者: Shalini Mishra, Saehee Lim, I seul Cho
更新时间: 2026-06-10
摘要: Black carbon (BC) is a major short-lived climate forcer whose physical properties critically influence its atmospheric lifetime, radiative impacts, and health effects. Across Asia, increasing numbers of observational studies have revealed substantial heterogeneity in BC concentration and physicochemical properties, underscoring its significant yet complex role in regional climate forcing. This review synthesizes recent advances in BC inventories, concentration, size distribution, mixing state, and associated optical enhancement, drawing from emission inventories, ground-based observations, and process-level studies. BC observations reveal pronounced spatial gradients across Asia, with urban concentrations ranging from ~0.5 to 25 μg m-3, declining to ~0.2 - 6 μg m-3 at suburban and rural sites, and remaining detectable at background and remote locations (~0.5 - 1.2 μg m-3). Mass median diameters (MMDs) vary widely from 120 – 280 nm, with fossil fuel-dominated conditions exhibiting smaller interquartile range of values (145 – 180 nm) and biomass burning showing shift toward larger MMDs (175 – 215 nm), albeit with overlap between source regimes. Observations accumulated since 2009 have quantified BC mixing state, consistently reporting relative coating thicknesses (RCT or Dp/Dc = 1.54 ± 0.31) and coated particle number fractions (Fthick = 48.29 ± 20.03%). Spatiotemporal variability in BC mixing state across Asia is governed by the interplay between emission sources, atmospheric aging, and meteorological conditions, with thicker coatings and higher coated fractions preferentially observed during stagnant boundary-layer conditions during pollution episodes that enhance secondary aerosol formation and particle residence time. Absorption enhancement by internally mixed BC typically ranges from 1.1 - 1.5, increasing up to ~2.0 during high pollution episodes due to secondary coatings in urban sites. Taken together, the results indicate that a better characterization of size- and source-dependent BC mixing state is needed to improve both climate-forcing estimates and assessments of population health impacts in Asia.

43. 题目: Impact of polysaccharides, proteins, lipids, and humic-like substances on thermal stability and flammability of wastewater sludge extracellular polymeric substances
文章编号: N26061004
期刊: Journal of Cleaner Production
作者: Tan Minh Le, Yuemei Lin, Wei-Qin Zhuang, Mark C M van Loosdrecht, Krishnan Jayaraman, Nam Kyeun Kim
更新时间: 2026-06-10
摘要: The current study investigates the application of extracellular polymeric substances (EPS), recovered from municipal wastewater sludge, as sustainable flame-retardant materials. While EPS show significant fire-safety potential, their compositional complexity requires a clear understanding of fire performance. The primary objective of this research is to elucidate how key EPS components, such as proteins (PN), polysaccharides (PS), lipids (LP), and humic-like substances (HS), govern thermal decomposition and flammability. Thermogravimetric analysis reveals that PN and HS have higher activation energies than those of other components, enhancing EPS thermal stability. PS yield the highest char residue (48.7% at 900 °C), while PN achieve the highest graphitisation degree, highlighting their crucial roles in char formation of EPS. Pyrolysis gas analysis indicates that PN and HS are main sources of nitrogenous compounds, diluting oxygen. Moreover, flammability tests show PS have the lowest peak heat release rate (29.7 W/g), underlining the important role in increasing flame-retardancy of EPS. However, TGA-FTIR analysis indicates lipid as a primary source of combustible gases likely due to their hydrocarbon chains. This study provides valuable insight into the role of major EPS components in the flame-retardant properties and suggest a sustainable approach to enhance flame retardancy through targeted component optimisation.

44. 题目: Mesospace-Domain Biochar Regulates Electron Transfer to Enhance Elemental Sulfur-Driven Autotrophic Denitrification for Low-Carbon Mariculture Wastewater Treatment
文章编号: N26061003
期刊: Water Research
作者: Yue Chen, Seibin Yoo, Subin Ahn, Hafiz Zargham Bin Imran, Yasmani Alba Reyes, Duc Viet Nguyen, Tayyebeh Soltani, Di Wu
更新时间: 2026-06-10
摘要: Elemental sulfur-driven autotrophic denitrification (S0AD) offers a promising approach for nitrate removal from recirculating aquaculture system (RAS) wastewater. However, it is constrained by the low bioavailability and restricted electron-donating kinetics of elemental sulfur (S0). This study developed an enhanced S0AD system based on mesospace-domain biochar-embedded hydrogel scaffolds (S0AD-BCgel) that modulated electron transfer to promote denitrification and enabled sulfur recovery. Biochar (pyrolyzed at 800°C; charBC800) increased denitrification efficiency and kinetics by 1.5-fold and 18.1-fold, respectively, compared to the biochar-free control. The improved S0AD was attributed to its three synergistic roles in regulating electron transfer: (i) a biopseudocapacitor with abundant quinone functionalities and high electron exchange capacity that facilitated electron relaying; (ii) a bioconductor with graphite-like structures that stimulated interfacial electron transfer; and (iii) a biomodulator that stimulated intracellular electron transfer and promoted extracellular electron transfer in extracellular polymeric substances by enriching cytochrome c and flavin-like compounds. These coordinated properties optimized S0 utilization and interspecific microbial interactions. Metagenomic assembled genomes (MAGs) further unveiled a shift in the denitrifying microbiota toward modularized consortia characterized by robust metabolic cross-feeding, underpinning improved S0AD stability. Moreover, spent hydrogels after S° consumption enable in-situ and ex-situ recovery of biogenic sulfur, supporting material reusability. These findings shed light on the mechanisms by which immobilized biochar regulated electron transfer and microbial interactions during S0AD within hydrogel matrices, providing valuable references for sustainable mariculture wastewater treatment and resource recovery.

45. 题目: Coupling polymer traits and environmental drivers to predict microplastic aging and DOC release in aquatic systems
文章编号: N26061002
期刊: Journal of Cleaner Production
作者: Pu Li, Yujia Xiao, Zekun Zhang, Yitian Zhong, Xiaomei Zhong, Baiyu Zhang, Kedong Zhang, Jie Yang, Haibo Niu
更新时间: 2026-06-10
摘要: Microplastic (MP) photoaging in aquatic environments reflects coupled controls from polymer traits and environmental forcing, yet transferable prediction across polymers remains limited. Here, we combine 32-day xenon-lamp photoaging experiments with a trait-environment kinetic framework for polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polyethylene (PE), using baseline-corrected carbonyl development (ΔCI) and polymer-mass-normalized DOC yields to quantify oxidation and dissolved-product export. Under the reference condition (100 μm, 0 psu, 0 rpm), PS showed the strongest oxidation development (ΔCI = 0.3163 at day 32), whereas PE and PET exhibited weaker ΔCI growth (0.0848 and 0.0415), and PVC remained near-zero/negative, consistent with non-carbonyl pathways. DOC increased monotonically for all polymers but diverged by day 32 (PS 1.2141, PVC 0.8765, PE 0.7041, PET 0.4626 mg g−1). Trajectory-based decoupling index metrics further showed that oxidation- and DOC-leading phases differed among polymer–treatment series. Across all scenarios, PS reached the highest DOC yield (2.1874 mg g−1 at 3 μm) while PET peaked under intensified mixing (0.9215 mg g−1 at 800 rpm), indicating that surface-area scaling and hydrodynamic forcing jointly regulate cumulative dissolved-product export with polymer-dependent sensitivity. Methodologically, we introduce a Monte Carlo-based trait-environment parameterization that maps fitted kinetic descriptors (ΔCImax, kCI, DOCmax, kDOC) to explicit predictive equations driven by polymer physicochemical traits and environmental conditions. This framework jointly predicts ΔCI and DOC from trait–environment coupling without using polymer identity as a categorical fitting term, achieving strong predictive performance across polymers and treatments (R2 = 0.8499–0.9983). Fluorescence characterization resolved three reproducible components that changed systematically with irradiation, indicating progressive changes in the optical signatures of dissolved products beyond bulk DOC.

46. 题目: Modeling soil organic carbon stocks and changes in agricultural cropping systems using a decision support tool and process-based model
文章编号: N26061001
期刊: Journal of Environmental Management
作者: Emileigh R Lucas, Elizabeth Ellis, Keith Paustian, Suzanne Dorsey, Gurpal S Toor
更新时间: 2026-06-10
摘要: Soil organic carbon (SOC) is a key indicator of soil health, yet changes in SOC often take decades to detect. Assessment tools, accessible to non-expert users, are needed to accurately and cost-effectively quantify SOC stocks. Soil sampling and analysis are ideal for quantification but are also resource- and time-intensive. A decision-support tool, COMET-Farm, could improve the transition to low-C agricultural supply chains; however, it was designed to estimate ΔSOC rather than SOC stocks directly, and its accuracy across diverse agricultural settings remains uncertain. We investigated whether the COMET-Farm tool could accurately estimate SOC stocks on 15 working farms in Maryland with variable management practices, including tillage, cover cropping, manure application, and irrigation. Field-measured SOC stocks (0–20 cm soil depth) of 17.1 to 73.6 Mg ha−1 were compared with model-predicted values using farmer-reported data in (i) COMET-Farm with default inputs supplied to DayCent, versus (ii) expert-applied DayCent. We found COMET-Farm predictions were lower than measured SOC stocks (R2 = 0.101; RMSE = 18.80 Mg ha−1), while expert-applied DayCent predictions more closely matched field measurements (R2 = 0.73; RMSE = 7.89 Mg ha−1). Poorly drained soils and long-term manure applications caused greater discrepancies between measured and predicted SOC. These findings suggest that COMET-Farm estimates could improve with better model initialization, more accurate site-specific soil data, such as measured soil texture and drainage conditions, and more regionally representative land-use histories. With these improvements and further testing, COMET-Farm could be expanded beyond its original purpose of estimating ΔSOC to directly estimate SOC stocks for non-expert users.

47. 题目: A self-perpetuating cycle: how heavy metals shape DOM chemistry to promote their own immobilization in soil.
文章编号: N26060904
期刊: Environmental Monitoring and Assessment
作者: Shuyi Zhang, Wenjun Zhang, Ye Li, Longfei Zhao, Chunmei Ran, Hongming Cai, Zhineng Hao, Junjie Zhang, Lei Wang
更新时间: 2026-06-09
摘要: Dissolved organic matter (DOM) plays an important role in the migration of heavy metals. However, the effect of heavy metal contamination on the characteristics of soil DOM has not yet been verified on field scale. In this study, DOM extracted from the soils of a site historically contaminated with heavy metals was compared with that extracted from the control soils. Although they had similar physical and chemical properties, vegetation coverage and microbial community structure, fluorescence spectrum showed that DOM from the in situ polluted soil (PS) had higher aromaticity and heavy metal complexation constant than that from the control soil (CS). Fourier-transform ion cyclotron resonance mass spectrometry revealed that PS-DOM had significantly higher concentrations of lignins, tannins, and heteroatoms as well as higher average molecular weight than CS-DOM. Density functional theory calculations confirmed the strong heavy metal complexation abilities of lignins and tannins, which explain the higher heavy metal complexation constant of PS-DOM than that of CS-DOM. Atomic force microscopy images revealed that the aggregate size of PS-DOM was larger than that of CS-DOM, and Cu2+ and Pb2+ caused obvious DOM aggregation. Complexation with heavy metals may affect DOM morphology and related environmental behaviors, resulting in difference in DOM characteristics of contaminated site.

48. 题目: Effects of low-molecular-weight organic acids and manganese-modified biochar application sequences on the environmental risk of soil cadmium and arsenic.
文章编号: N26060903
期刊: Environmental Geochemistry and Health
作者: Yongqiang Yang, Mingjun Li, Yipan Zhao, Liping Li, Yale Wang, Weiqin Xing, Chunhong Xu, Qipo Yang, Yali Wang, Yu Liu
更新时间: 2026-06-09
摘要: Although manganese-modified biochar (MBC) effectively immobilizes Cd and As, the effects of low-molecular-weight organic acids (LA) on the performance and efficiency of Cd and As remediation in agricultural soils when co-applied with MBC in different application sequences remain unclear. This study examined the effects of LA on the MBC-mediated remediation of Cd/As-contaminated soil via the immersion of MBC in LA and LA-MBC to facilitate co-applications on contaminated soil using different application sequences. Results revealed that after LA immersion, the pH of MBC decreased by 0.14-2.10 units, accompanied by increases in electrical conductivity and Mn concentration. LA treatment also induced surface alterations characterized by cracks, depressions, reduced Mn oxide particles, and weakened MnO2 diffraction peaks. These changes promoted soil Cd/As mobilization, increasing the TCLP-Cd by 40.2-110.1% and available As by 22.0-70.0%, thereby reducing MBC immobilization efficiency. Application sequence markedly affected the remediation outcomes, in order of decreasing remediation effectiveness: LA pre-addition > MBC pre-addition > simultaneous application. Simultaneous LA-MBC application led to a 12.4-62.6% decrease in the relative abundance of soil Gemmatimonadota. In contrast, the relative abundance of Firmicutes and Myxococcota increased by 47.0-184.9% and 39.5-273.8%, respectively. This study systematically assessed the effects of LA and MBC application sequences at different time intervals on the bioavailability of Cd/As. A LA-MBC-microorganism interaction model is proposed, demonstrating that LA structurally reshapes MBC and alters microbial communities, which may modulate Cd/As speciation. Based on pollutant behavior and amendment dynamics, a spatiotemporally optimized strategy is proposed to improve in situ remediation and reduce environmental risks.

49. 题目: A Synergistic Molecular Mechanism Defines Pyrogenic Dissolved Organic Matter (pyDOM) Coagulation.
文章编号: N26060902
期刊: Environmental Science & Technology
作者: Baoju He, Yixuan Mao, Longyi Ran, Hanqian Pan, Sheng-Ao Li, Hua Ma
更新时间: 2026-06-09
摘要: Climate change is exacerbating wildfires, resulting in an increased influx of pyrogenic dissolved organic matter (pyDOM) into aquatic systems. The distinctive molecular signature of pyDOM, which is markedly different from that of conventional humic substances, is hypothesized to have an impact on its environmental fate, especially during coagulation that is a crucial process for carbon sedimentation and water purification. Nevertheless, the specific removal mechanisms and the resulting floc architectures remain unclear. Through a comparative investigation of pyDOM from subtropical burnt soils and standard humic acid (HA) during aluminum sulfate coagulation, we have discovered a selective coagulation mechanism governed by pyDOM's molecular properties. pyDOM with condensed aromatics and oxygenated aliphatics is removed via synergistic π-π stacking and Al coordination. This stands in stark contrast to the charge neutralization dominated pathway observed for HA. The pyDOM-specific pathway gives rise to larger, denser flocs with a wider size distribution. At the molecular level, aggregation initiates with the condensation of aromatic cores, and oxygen and heteroatom functional groups form stable Al-O-C complexes, acting as chemical cross-links that strengthen floc integrity. This research identifies a previously neglected coagulation paradigm unique to pyDOM, which differs fundamentally from the traditional HA-centric framework, thus enhancing our mechanistic understanding of pyDOM-driven particle assembly and carbon export. These findings are essential for precisely predicting carbon stability in fire-affected watersheds and for devising effective water treatment strategies in wildfire-prone regions.

50. 题目: Sunlight Switches Natural Organic Matter (NOM)-Mediated Redox Pathways and Suppresses CeO2 Nanoparticle Dissolution.
文章编号: N26060901
期刊: Environmental Science & Technology
作者: Yixin Tan, Zixin Han, Bei Liu, Aling Wan, Mengxia Wang, Weiwen Chen, Chaoqun Zhu, Yufei Shu, Zhongying Wang
更新时间: 2026-06-09
摘要: The environmental transformation of engineered CeO2 nanoparticles is strongly mediated by natural organic matter (NOM); however, the interplay between NOM and light in regulating their fate remains unclear. Here, we systematically investigated the dissolution behavior of CeO2 in the presence of NOM under dark and illuminated conditions. Results revealed that NOM-induced Ce3+ release was significant in the dark but suppressed under visible light, which is a striking phenomenon validated in both aqueous and soil systems. Spectroscopic and microscopic analyses reveal that in the dark, the carbonyl-rich aliphatic components of NOM preferentially coordinate with Ce(III) at the oxygen vacancy sites of CeO2, promoting continuous ligand-driven Ce3+ release. Under visible light, however, the dominant interfacial redox pathway shifted. We found that the photoactivation of quinone chromophores within macromolecular NOM diverts interfacial electron transfer away from surface Ce(IV) reduction toward dissolved O2, initiating a cascade of reactive oxygen species (ROS) formation that degrades NOM and stabilizes the CeO2 surface against dissolution. In contrast to previously reported light-enhanced dissolution of metal oxides by NOM, this work reveals that the effect of NOM photochemistry is fundamentally governed by the intrinsic dissolution pathway of the oxide and thus provides a conceptual basis for predicting when illumination will enhance or suppress metal release in natural environments.

51. 题目: Mechanistic insights into nZVI-enhanced denitrification resilience in biological aerated filters under chlorfenapyr stress: Roles of EPS stability and electron-transfer pathways
文章编号: N26060712
期刊: Water Research
作者: Liangjie Li, Jiawei Jiang, Yufan Liu, Zhilin Xing, Tiantao Zhao
更新时间: 2026-06-07
摘要: To address the decline in nitrogen removal performance of biological aerated filters (BAFs) caused by the inhibition of key denitrification processes by the arylpyrrole insecticide chlorfenapyr, this study established a nanoscale zero-valent iron (nZVI)-enhanced BAF system and systematically investigated the enhancement effects and regulatory mechanisms of nZVI. The results demonstrated that nZVI markedly improved shock load resistance and recovery resilience. The NH4+-N removal efficiency remained above 90% under different chlorfenapyr concentrations, while the total nitrogen (TN) removal efficiency reached up to 88.82%. Extracellular polymeric substance (EPS) analysis indicated that nZVI effectively mitigated the adverse effects of stress on the surface properties of the biofilm, maintaining the protein-to-polysaccharide ratio at approximately 2.0 and thereby preserving biofilm structural stability. High-throughput sequencing revealed that nZVI sustained microbial community diversity and evenness. The relative abundance of the dominant phylum Pseudomonadota consistently remained above 54%, and the targeted enrichment of functional genera such as Paracoccus and members of Rhizobiaceae was promoted. Integrated analysis of carbon and nitrogen metabolic pathways had revealed that nZVI, acting as an electron donor, had promoted the TCA cycle while significantly upregulating the expression of iron transport genes (afuABC) and key denitrification genes (napA, nirB, and nosZ). From the perspectives of electron transfer and microbial community ecology, this study elucidates the intrinsic mechanisms by which nZVI enhances the stress resistance of biological systems, providing a theoretical basis for the engineering treatment of refractory pesticide wastewater.

52. 题目: Cooperation between cellulose-degrading complex microflora and enzymes on improving soil organic carbon turnover and stabilization in the saline-alkali soils
文章编号: N26060711
期刊: Applied Soil Ecology
作者: Sainan Gao, Xuelian Liu, Chong Wang, Haoyue Qin, Honghao Cheng, Xueya Liu, Mengli Liu
更新时间: 2026-06-07
摘要: Straw incorporation is a popular practice for enhancing soil organic carbon (SOC). However, the severe environmental characteristics of saline-alkali soils suppress microbial activity and extracellular enzyme production, thereby constraining the transformation and stabilization of straw-derived carbon into SOC. The application of straw-degrading microorganisms or hydrolytic enzymes can substantially accelerate straw decomposition. This research was conducted to study the synergistic cooperation between cellulose-degrading complex microflora and enzymes on the transformation of straw carbon into SOC in saline soil. Results indicated that enzymatic significantly increased the cellulose and hemicellulose decomposition at 30 days, while the complex microflora significantly enhanced overall straw decomposition and substantially increased SOC content at 60 days by promoting the decomposition of cellulose, hemicellulose and lignin in saline soils. These results suggested that complex enzymes primarily function during the early stages, whereas complex microflora exert their effects predominantly during the later stages. During the early stages, the synergistic application of cellulose-degrading complex microflora and enzymes increased Ascomycota abundance and genes associated with labile carbon degradation, thereby enhancing the efficiency of straw-derived carbon conversion into SOC. In the later stages, the synergistic effects promoted the conversion of particulate organic carbon (POC) to mineral-associated organic carbon (MAOC) by increasing Basidiomycota abundance and genes associated with recalcitrant carbon degradation. Overall, this study demonstrates a temporally coordinated cooperation between complex microflora and enzymes on the regulation of SOC turnover and stabilization in saline-alkali soils.

53. 题目: Fungal necromass carbon mediates soil organic carbon under film mulch regimes in a potato cropping system
文章编号: N26060710
期刊: Applied Soil Ecology
作者: Mei Zhang, Furong Du, Ke Li, Mingming Zhao, Xinyan Hu, Xiaoguang Chen
更新时间: 2026-06-07
摘要: Microbial necromass carbon (MNC) is an important component of soil organic carbon (SOC). While film mulch is known to influence the accumulation of SOC, the microbial processes by which different mulch regimes regulate SOC via MNC remain poorly understood. This study aimed to elucidate how different film mulch regimes influence SOC accumulation, MNC content, and microbial community characteristics in a potato cropping system. We conducted a 2-year field experiment in the Huang-Huai-Hai Plain of China under five treatments: non-mulch film (non-mulch), black film (black), black film & shed film (black+shed), white film (white), and white film & shed film (white+shed). 16S and ITS rRNA amplicon sequencing and amino sugar biomarker analyses were used to assess the changes in the soil microbial communities, extracellular enzymes, fungal (FNC) and bacterial necromass carbon (BNC). Compared to the other treatments, the white treatment considerably increased SOC content, accompanied by the highest MNC and FNC (p < 0.05). Notably, FNC contributed an average of 17.1% to SOC, far exceeding the 1.9% contribution from BNC (p < 0.05), indicating that FNC played a more crucial role than BNC in promoting SOC accumulation. Variations in soil available nutrients (N, P) and N-acquiring enzymes primarily shaped microbial community composition, particularly altering the abundance of Firmicutes and Ascomycota, which largely facilitated the accumulation of FNC. These findings highlight the key role of FNC in SOC sequestration and identify white film mulch is the optimal practice to enhance the accumulation of SOC.

54. 题目: Impact of management intensity of agricultural systems and soil intrinsic characteristics on soil organic carbon stocks
文章编号: N26060709
期刊: Agriculture, Ecosystems & Environment
作者: Alex Castellón Meyrat, Lilian O’Sullivan, Paul Holloway, David Wall, Giulia Bondi
更新时间: 2026-06-07
摘要: Enhancing carbon in soils is crucial for improving soil health and building sustainable agroecosystems. Inherent SOC stocks are site-specific and vary due to complex interactions between climate, soils, land use, and management practices. However, the coupled effects of these factors on SOC dynamics are not fully understood. This research aimed to evaluate the impact of different management regimes and intrinsic soil characteristics on SOC stocks and identify pathways that can boost carbon sequestration in agricultural soils. This study relied on data of 143 soil profiles distributed across the south of Ireland. Each site was sampled at four depths (0–15, 15–30, 30–45, and 45–60 cm) and characterized according to the land use and management practices implemented over the past five years. A Regression Tree (RT) model was employed to estimate the single and combined contribution of key soil properties and management practices on SOC stocks. Overall, intrinsic soil characteristics, especially the presence of humic layers and clay, are decisive to determine the SOC storage potential in soils. Land use and management practices primarily impact the top 15 cm, and their accumulated effect (e.g. stocking rates in grassland systems) can shift SOC stocks trends over time. Finally, the heterogeneity in subsoils controls the variability of SOC stocks in depth. The outcomes of this study can help tailor carbon farming strategies to boost carbon sequestration accounting for specific soil conditions.

55. 题目: Fungal residue dominates soil organic carbon accumulation during vegetation restoration
文章编号: N26060708
期刊: Catena
作者: Shu Zhu, Jiwei Li, Zhenhao Wei, JianZhao Wu, Ziyuan Liu, Zhouping Shangguan, Lei Deng
更新时间: 2026-06-07
摘要: Microbial residue carbon (MRC) plays a critical role in soil carbon cycling and stabilization under global climate change. However, how vegetation restoration affects MRC accumulation remains unclear. In this study, we compiled 817 field observations to investigate the effects of vegetation restoration on MRC accumulation at a global scale. The results showed that vegetation restoration increased MRC, fungal residue carbon (FRC), and bacterial residue carbon (BRC) by 39.9%, 46.6%, and 34.3%, respectively, while the FRC/BRC ratio remained relatively stable. Vegetation restoration enhanced the contribution of FRC to soil organic carbon by 8.3%, highlighting its crucial role in carbon stabilization. Grassland restoration led to a greater increase in MRC (+52.1%) compared with natural succession (+36.6%) and afforestation (+24.8%). In addition, vegetation restoration in arid regions led to larger increases in both MRC (+44.1%) and FRC (+57.6%) than in humid regions (+35.3%, +35.2%, respectively). Collectively, our results reveal that fungal residues played a key role in soil organic carbon accumulation, which is primarily regulated by soil pH, the fungal-to-bacterial ratio, and nutrient availability following vegetation restoration. These findings clarify how soil pH regulates fungal pathways to facilitate carbon sequestration during vegetation restoration.

56. 题目: Biochar increased water productivity and grain yield of winter wheat by alleviating post-anthesis drought stress under limited irrigation
文章编号: N26060707
期刊: Agricultural Water Management
作者: Ying Liu, Zhen Gao, Wanshun Li, Yanfei Liu, Teng Fei, Xudong Zhao, Wenchao Zhen, Jianhong Ren
更新时间: 2026-06-07
摘要: Post-anthesis drought is the main limited factor for winter wheat production under limited irrigation in the North China Plain (NCP). Application of biochar has been demonstrated as an effective measure to alleviate water deficit stress. Therefore, a field experiment was conducted at the Xinji Experimental Station, Hebei, China, over the two wheat growing seasons (2023–2024 and 2024–2025) to clarify the combined effects of irrigation and biochar on soil-root-canopy traits. The main plots consisted two limited irrigation regimes, i.e., W1 (75 mm irrigation at the jointing stage) and W2 (75 mm irrigation at the jointing and anthesis stage, respectively); sub-plots included four biochar application rates, i.e., 0, 3, 6, and 9 t ha−1 (B0, B3, B6, and B9). Biochar reduced soil bulk density but significantly increased field water capacity, which increased the root length density and root surface area density in the topsoil layer. During the grain filling stage, biochar (B3 and B6) sustained high SPAD values and relative water content in flag leaves. It also significantly alleviated leaf senescence (as evidenced by higher SOD and lower MDA) and increased photosynthesis rate. Accordingly, starch content in spikes and post-anthesis dry matter accumulation both increased. Additionally, when soil moisture was relatively sufficient (W2 and W1 in rainy 2024), the application of biochar resulted in higher water use. W2B3 showed the most significant yield increase, with a 9.2%-10.5% increase compared to W2B0, while W1B6 showed the most significant yield increase, with a 5.4%-8.7% increase compared with W1B0. Averaged across two seasons, biochar application significantly enhanced water productivity by 2.0%-4.5%. We concluded that moderate biochar could effectively optimize soil and root properties, mitigate leaf senescence and increase grain yield of winter wheat under limited irrigation in the NCP.

57. 题目: Extracellular polymeric substances reprogram the environmental behavior and impact of silver nanoparticles on Chlamydomonas reinhardtii
文章编号: N26060706
期刊: Environmental Pollution
作者: Rocco Gasco, Arin Kantarciyan, Vera I Slaveykova
更新时间: 2026-06-07
摘要: Engineered nanoparticles, and silver nanoparticles (nAg) among them, can be released into aquatic environments, where interactions with natural biomolecules can significantly alter their environmental behaviour and toxicity. Recognizing the growing need to integrate ecocorona processes into nanoparticle risk assessment, this study investigates extracellular polymeric substances (EPS) from green alga Chlamydomonas reinhardtii as key environmental modulators of nAg transformations and biological effects. The behaviour of citrate-coated (Cit-nAg) and lipoic acid-coated (Lip-nAg) nanoparticles in the presence and absence of environmentally relevant concentrations of algal EPS was evaluated through combined physicochemical characterization and ecotoxicological assays to assess EPS-driven changes in aggregation dynamics, dissolution behaviour, and toxicity toward freshwater phytoplankton. EPS adsorption markedly reshaped nAg behaviour in a coating-dependent manner: while EPS enhanced colloidal stability for both materials, it reduced Ag+ release and toxicity for Cit-nAg, but promoted dissolution and amplified biological effects for Lip-nAg, showing the potential dual role of phytoplankton EPS in shaping nAg identity in freshwater. These results reveal that EPS-driven ecocorona formation can either mitigate or enhance nAg toxicity depending on the underlying surface chemistry. By demonstrating how environmentally derived biomolecules regulate the coupling between nanoparticle transformations and toxicological responses, this study supports the critical role of ecocorona formation as a central component in environmentally realistic assessments of nanomaterial fate and risk.

58. 题目: Per- and polyfluoroalkyl substances (PFASs) in humus-mineral layers of forest soils: Distribution, key drivers, and leaching rates
文章编号: N26060705
期刊: Environmental Research
作者: Ying Liu, Weijie Liu, Yili Zou, Andrew J Sweetman, Yao Mao, Tianpeng Hu, Jiaquan Zhang, Shihua Qi, Xinli Xing
更新时间: 2026-06-07
摘要: The toxicity and persistence of per- and polyfluoroalkyl substances (PFASs) have made their widespread environmental contamination a significant global issue. Forests can uptake and trap PFASs from the atmosphere, but their environmental behavior and fate in forest humus layer and mineral soil remain unclear. This study investigated PFAS distribution, drivers, and leaching rates in Mt. Shennongjia, China. The concentrations of total PFASs (Σ24PFAS) in the humus layer (average of 5.67 ng/g) were higher than in mineral soil (2.79 ng/g), with long-chain perfluoroalkyl carboxylic acids (PFCAs) (46.8%-59.3%) being the predominant PFASs. Spatial distribution and correlation analysis indicates that, altitude and forest vegetation types influence the accumulation of PFASs in forest humus and soil. The concentration of PFASs generally increased with increasing altitude, and the sub-alpine conifer forest exhibited higher PFASs level than other vegetation types. The concentration of PFASs was positively correlated with the TOC content (r = 0.356-0.745, p < 0.05). Enrichment factors (EF) of PFAS varied from 0.14 to 2.22, and EFs decreased with increasing carbon chain length, suggesting long-chain PFASs have a greater propensity to partition into humus. The leaching rates of PFAS from the humus layer in freely dissolved forms were significantly higher than those in the dissolved organic matter forms (p < 0.05). Short-chain and carboxylate-headed PFASs showed greater downward leaching potential, more attention should be paid to their transport to groundwater in ecologically sensitive areas.

59. 题目: Long-term operated constructed wetlands: High organic carbon storage and autochthonous carbon dominance
文章编号: N26060704
期刊: Bioresource Technology
作者: Guosheng Zhang, Qingju Hao, Jiawei Ren, Yuhang He, Xiaoran Peng, Kesong Pu, Biqin Hu, Changsheng Jiang
更新时间: 2026-06-07
摘要: Constructed wetlands (CWs) are engineered landscapes designed to replicate the functions of natural wetlands, serving as substantial sinks for sediment organic carbon (SOC). However, the seasonal dynamics of SOC composition and dissolved organic matter (DOM) characteristics, as well as their roles in autochthonous carbon cycling, remain poorly understood. This study investigated a typical long-term (over 13 years) operated CW in Chongqing, China, to elucidate the seasonal variations of sediment particulate organic carbon (POC) and mineral-associated organic carbon (MAOC). By integrating ultraviolet–visible spectroscopy, three-dimensional fluorescence spectroscopy, and microbial sequencing, we explored the relationships among DOM characteristics, greenhouse gas (GHG) emissions, and microbial communities. The results indicated that the CW sediments exhibited high SOC accumulation, which was dominated by MAOC (averaging 61.5% of SOC). MAOC exhibited significant seasonal fluctuations, reaching a minimum in autumn (96.9 ± 27.1 g·kg−1) and peaking in winter (130.3 ± 17.6 g·kg−1), whereas POC remained relatively stable. Spatial SOC variations were driven by plant species, with zones dominated by fibrous-rooted Hydrocotyle vulgaris accumulating higher levels than those with Acorus calamus. DOM primarily consisted of protein-like components (averaging a 69.4% contribution), exhibiting strong autochthonous characteristics and a low degree of humification. CO2 was the dominant GHG emitted from sediment, and its emissions correlated strongly with protein-like DOM. The microbial communities displayed significant seasonal shifts, exhibiting higher relative abundances of denitrifying genera (e.g., Dechloromonas) in winter than in summer. These findings highlight the seasonal dynamics of MAOC as a critical regulator for carbon storage and turnover in CWs, offering insights into sediment organic matter stabilization within engineered landscapes.

60. 题目: Changing pH, organic matter, and redox state govern contaminant mobility during waste stabilization in landfill simulation reactors
文章编号: N26060703
期刊: Journal of Hazardous Materials
作者: Nick Quist, Frank van Raffe, Joris J Dijkstra, Rob N J Comans
更新时间: 2026-06-07
摘要: Landfills remain an important endpoint for waste and waste residues, yet current management in the Netherlands requires eternal aftercare to protect public health and the environment. Enhanced waste stabilization in landfills through active treatment, i.e. aeration and leachate recirculation, has potential as a sustainable alternative to current landfill management. However, the influence of active treatment on solid waste properties and subsequent leaching of hazardous contaminants has only received limited investigation. This study investigates these influences in landfill simulation reactors containing 30kg of waste from different origins, which were treated using aeration, leachate recirculation, and their combination. Large differences in leachate contaminant concentrations were found between treatments. A shift from leachate recirculation to aeration changed prevailing redox conditions from anaerobic to aerobic and decreased pH and dissolved organic and inorganic carbon. Consequently, concentrations of ammonium and inorganic contaminants with a high organic matter binding affinity decreased, whereas other inorganic contaminants first increased in concentration due to mineral dissolution followed by a decrease due to mineral precipitation or binding to reactive surfaces. The underlying mechanisms of these trends were identified based on geochemical modelling. The observed changes during aeration were accelerated when aeration was preceded by leachate recirculation, and concentrations rebounded when anaerobic conditions were reintroduced. Our findings ultimately demonstrate that active treatment of landfills requires careful consideration of the most effective strategy, as trade-offs in contaminant leaching mean their potential risks should be weighed against each other.