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61. 题目: Evaluating the effect of natural organic matter quality on the bioavailability of a rare earth element (La)
文章编号: N26090601
期刊: Environmental Pollution
作者: Marie-Hélène Brunet, Laurianne Pagé, D Scott Smith, Aleicia Holland, James C McGeer, Kevin J Wilkinson
更新时间: 2026-09-06
摘要: Rare earth elements (REE) are in high demand due to their applications in the medical, green energy and high-tech industries. As a result, new REE mines are being developed with the potential of mobilizing REE and increasing their concentrations in the environment, including in landfills, wastewaters and natural waters. Unfortunately, the concentrations of trivalent REE cations are generally poorly predictive of biological effects, especially when attempting to understand the role of REE complexation within bioavailability models, such as the Biotic Ligand Model (BLM). We investigated the bioavailability of a representative REE, lanthanum (La), by measuring biouptake fluxes for Chlamydomonas reinhardtii. In the presence of a small amount (0.5 mg C L-1) of natural organic matter (NOM), for a calculated reduction in La3+ of >90%, La biouptake decreased between 43 to 87%. Furthermore, the concentration of dissolved organic carbon was not sufficient to predict the effect of NOM on La biouptake, with the effect varying greatly as a function of NOM origin. Eleven NOM samples were extensively characterised in order to relate NOM quality to its effect on biouptake. The most aromatic and allochthonous NOM had the greatest effect on reducing La biouptake. For example, for an NOM concentration of 10 mg C L-1, the most allochthonous NOM tested (Suwannee River Humic Acid, fluorescence index=1.2) reduced La biouptake by 95% as compared to a reduction of 67% for the most autochthonous NOM (Cameroun River, fluorescence index=1.9). The study is useful for improving our understanding of the important factors affecting REE bioavailability in natural systems.

62. 题目: Co-composted biochar and iron-modified biochar enhance soil bioavailable phosphorus fractions by altering gcd- and phoD-harboring microbial communities
文章编号: N26090518
期刊: Environmental Technology & Innovation
作者: Xinxin You, Liuhong Wang, Pianpian Wu, Xiuxin Wang, Ziyang Ding, Wenyi Xu
更新时间: 2026-09-05
摘要: Organic fertilizers and biochar amendments can improve soil quality and facilitate phosphorus (P) availability. However, how co-composted biochar and iron-modified biochar affect soil P fractions and P-functional microbial communities remain uncertain. Herein, pot experiments amended with chemical fertilizer (CF), sole compost from pig manure (OF), co-composted general biochar (BOF), and co-composted iron-modified biochar with different application rates (FeBOFs) were conducted. Variations in bioavailable P fractions, soil stoichiometry, and plant properties were examined, metagenomic sequencing and high-throughput quantitative PCR (qPCR) were also performed to investigate the responses of P-cycling microbial communities and functional genes to the different amendments. Notably, FeBOFs significantly enhanced soil P availability and promoted plant P uptake compared with BOF. Although the BOF treatment had the highest soil Citrate-P, Enzyme-P and HCl-P contents, FeBOFs altered the distribution of bioavailable P fractions, indicated a greater capacity to facilitate the transformation of available P. Importantly, BOF and FeBOFs amendments shifted the composition and diversity of gcd- and phoD-harboring microbial communities. Correlation and partial least squares path analyses revealed contrasting effects of BOF and FeBOFs amendments on gcd- and phoD-harboring microbial communities. In addition, gcd-harboring microbes positively associated with P functional genes and potentially altered soil P availability. In contrast, phoD-harboring microbes directly related to soil bioavailable P fractions. Our findings offer new insights into the responses of gcd- and phoD-harboring microbial community to distinct types of co-composted biochars, highlighting their divergent roles in the microbial transformation of soil P fractions.

63. 题目: Towards evidence-based environmental regulation of biochar for agricultural use: Inorganic composition and environmental quality of biochar
文章编号: N26090517
期刊: Environmental Technology & Innovation
作者: Raissa Rossi, Wolfgang Stelte, Mikael Emil Olsson, Philipp Mayer, Giulia Ravenni
更新时间: 2026-09-05
摘要: Biochar produced via slow pyrolysis is increasingly used for carbon sequestration, waste valorization, and soil amendment. As pyrolysis systems are implemented at larger scales, robust assessment of biochar quality and contaminant content is essential to support regulatory development and ensure environmental safety. This study compares straw, biogas residue fibers (BRF), and sewage sludge, together with their corresponding biochar produced at laboratory and industrial scales. Total concentrations of selected heavy metals and metalloids, fluoride (F⁻), chloride (Cl⁻), and nutrients (N, P, and K) were determined and evaluated against existing quality standards. Feedstock type was the primary factor controlling contaminant concentrations in biochar. Sewage sludge-derived biochar exhibited the highest heavy metal concentrations, whereas straw-derived biochar consistently showed the lowest levels. Comparison with existing standards indicated that sludge-derived biochar exceeded the Cu and/or Zn limits, while BRF- and straw-derived biochar generally complied with guideline values. Among the investigated elements, Cu and Ni exhibited the highest retention during pyrolysis, whereas Cd and As were the most volatile, with fixation rates decreasing markedly at elevated temperatures. Halogen behavior was also matrix dependent. Fluoride retention was highest in sludge-derived biochar, whereas chloride was only partially retained, with fixation rates generally below 60%. Overall, biochar quality was governed primarily by feedstock composition, whereas pyrolysis conditions controlled the retention and volatilization of specific elements. These findings provide new evidence to support the development of science-based criteria for agricultural use of biochar and its regulation.

64. 题目: Molecular insights into the transformation of dissolved organic matter from refinery wastewater in receiving water: Photochemical and photo-microbial effects
文章编号: N26090516
期刊: Journal of Environmental Chemical Engineering
作者: Leqi Wang, Lei He, Zhuoyu Li, Haifeng Rong, Yifei Zhu, Zelin Niu, Chunmao Chen, Qinghong Wang
更新时间: 2026-09-05
摘要: The environmental risk of refinery-derived dissolved organic matter (DOM) is closely tied to its transformation, yet the effects of photochemical and photo-microbial processes remain poorly constrained. In this study, we systematically evaluated the photochemical and photo-microbial transformation of refinery-derived DOM in receiving water. Using ultra-high-resolution mass spectrometry (Orbitrap MS) coupled with 16S rRNA gene sequencing, we resolved the compositional shifts of DOM and identified the key mechanisms governing its transformation. We found that, compared with photochemical transformation, photo-microbial processes substantially enhanced dissolved organic carbon loss. The compositions of labile and newly formed DOM differed markedly between photochemical and photo-microbial transformations, whereas resistant DOM exhibited similar characteristics in both processes. Photochemical transformation primarily led to the predominance of CHOS-like molecules among both photochemically labile and newly produced DOM through desulfurization and oxidation reactions (−S+O), driven by reactive intermediates. In contrast, photo-microbial transformation mainly facilitated the conversion of CHO-like DOM and the formation of CHNO-like compounds through –CO₂, –C₂H₂O, –CH₂, and + NO₂–H reactions, jointly driven by reactive intermediates and the enrichment of nitrogen-fixing and carbon–nitrogen–linking bacterial genera. These findings provide novel molecular-level insights into the divergent transformation pathways of refinery-derived DOM under photochemical and photo-microbial conditions, advancing the understanding of its environmental fate in natural aquatic systems.

65. 题目: Urea-melamine-derived nitrogen-doped biochar flow electrodes for enhanced treatment of nickel-containing electroplating wastewater
文章编号: N26090515
期刊: Journal of Environmental Chemical Engineering
作者: Jian Peng, Ziyi Deng, Wei Liu, Hande Zhang, Yangxiong Huang, Ruixiong Huang, Rikun Lai, Yong Yang, Jianyou Long, Wubiao Lin, Jie Shu, Huosheng Li
更新时间: 2026-09-05
摘要: Nickel (Ni)-containing electroplating wastewater presents treatment challenges due to coexistence with high concentrations of background salts. Herein, a flow-electrode capacitive deionization (FCDI) system with urea/melamine co-modified nitrogen-doped biochar electrodes was developed for simultaneous removal of Ni2+ and SO42- from real electroplating wastewater. Among a series of one-pot pyrolyzed N-doped biochars, the electrode prepared at a urea-to-melamine mass ratio of 1:2 exhibited the best performance, featuring a hierarchical pore structure and abundant nitrogen-containing functional groups that enhance charge storage, ion transport, and interfacial binding. At 2.4V, the optimized FCDI system achieved removal efficiencies of 99.81% for Ni and 96.05% for SO42-, while maintaining the effluent Ni concentration below 0.25mg/L during ten consecutive reuse cycles. Notably, Ni2+ removal already exceeded 94% at 0.8V while the bulk pH remained below 8, demonstrating that high Ni2+ removal did not depend solely on hydroxide precipitation. Combined characterization indicates that Ni2+ removal involved electric double-layer electrosorption, N/O mediated surface coordination, K+/Ni2+ exchange, and electrochemically induced precipitation, while SO42- retention was promoted by hydrogen bonding and Ni2+-SO42- ion-pair association. Density functional theory calculations further suggest that pyridinic nitrogen served as a favorable interfacial site for binding Ni2+-SO42- ion-pair, with a binding energy of -1.02eV, markedly stronger than that on monolayer graphene (-0.48eV). These findings clarify the role of nitrogen functionalities, especially pyridinic nitrogen, in strengthening ion-pair capture at the flow-electrode interface and demonstrate the potential of nitrogen-doped biochar-based FCDI for the purification of Ni-rich electroplating wastewater.

66. 题目: Long-term monitoring of dissolved organic matter using a multi-analytical approach reveals spruce decline as a primary driver of soil solution browning
文章编号: N26090514
期刊: Geoderma
作者: Adrien Saphy, Marie-Noëlle Pons, Sophie Rihs, Jeremy Masbou, Emilie Beaulieu, Marie-Claire Pierret
更新时间: 2026-09-05
摘要: Surface water browning is a widespread phenomenon in the Northern Hemisphere, although its underlying drivers remain debated. In this study, we combined 20 years of dissolved organic carbon (DOC) measurements with five years of optical characterization in soil solutions collected at multiple depths from two contrasting forest plots in the Strengbach catchment (Vosges Mountains, France): a spruce stand affected by dieback and a beech stand. We developed a conceptual framework to interpret the optical properties of DOC in soil solutions, based on commonly used indices and distinguishing between two endmembers: litter-derived and microbial-derived signatures. Our results reveal a marked browning in soil solutions associated with spruce decline, characterized by increasing DOC and aromaticity. DOC concentrations increased significantly at several soil depths between 2004 and 2024, with an intensified increase following bark beetle infestation in 2013, reaching up to 2 ppm-C/year at 5 and 30 cm depth. This increase was accompanied by a shift towards more litter-derived DOC and a concomitant decrease in microbial-derived signatures, exacerbated in deeper soil solutions. A soil sequence representing a post-decline gradient further demonstrated that spruce decline increased soil lignin content, resulting in higher DOC and aromaticity in soil solutions, driven by litter input changes. The reduced microbial activity following clear-cut may explain the lower microbial signature. Overall, the disturbance of forest cover associated with spruce decline is a major driver of soil solution browning, raising concerns regarding the quality of downstream surface waters.

67. 题目: Spatial prediction of soil organic matter content in croplands using bare soil composite images generated under spatial pattern similarity constraints
文章编号: N26090513
期刊: Geoderma
作者: Fei Wang, Feng Liu, Tianyun Shao, Peiyu Zhang
更新时间: 2026-09-05
摘要: Remote sensing images provide valuable soil spectral information for predicting soil organic matter (SOM) content. However, environmental factors, such as surface roughness, soil moisture, and crop residues, can interfere with soil spectral responses, rendering many bare soil images unsuitable for accurate SOM quantification. This study proposes a bare soil image selection approach based on spatial pattern similarity for SOM prediction. An agricultural region in central Jiangsu Province, China, was selected as the study area. Bare soil pixels were extracted using the Google Earth Engine (GEE) platform from MOD09A1 images acquired in January, November, and December from 2001 to 2024. Bare soil images exhibiting similar spatial patterns were identified from multitemporal observations and subsequently composited to generate a series of similarity-based bare soil composite images (SBSCI_p10–p90). These composite images were then evaluated for SOM prediction, with further comparison against the conventional bare soil composite image (CBSCI), both with and without soil-forming factors. Spatial cross-validation results showed that SBSCI_p70 yielded the highest R2 (0.27) and the lowest RMSE (6.66) among the evaluated SBSCIs. Compared with the CBSCI (R2 = 0.23 and RMSE = 6.86), SBSCI_p70 showed improved SOM prediction accuracy. Similar results were observed after incorporating soil-forming factors, with the SBSCI_p70-based model yielding a higher R2 (0.40) and a lower RMSE (6.04) than the CBSCI-based model (R2 = 0.36 and RMSE = 6.25). These results suggest the potential of spatial pattern similarity in selecting bare soil images for SOM prediction.

68. 题目: High-resolution mapping of soil organic carbon using multi-source remote sensing and hybrid models: Addressing spatial heterogeneity via regionalized modeling
文章编号: N26090512
期刊: Soil and Tillage Research
作者: Xinle Zhang, Ying Zhan, Huanjun Liu, Xiangtian Meng, Zhuyuan Qin, Zhendong Yang, Yun Wang
更新时间: 2026-09-05
摘要: Accurate soil organic carbon (SOC) mapping is vital for sustainable agriculture in black soil regions. Although remote sensing offers an efficient and cost-effective approach for characterizing the spatial distribution of SOC, three major bottlenecks persist: single source data cannot fully represent SOC dynamics, traditional models struggle with complex nonlinearities, and spatial heterogeneity limits global models from reflecting local pedogenic mechanisms. To address these, this study developed a hybrid framework for the Songnen Plain integrating a zonal ensemble strategy with deep learning. Using Google Earth Engine, a dataset was constructed with multi-temporal Sentinel-1 radar, Sentinel-2 optical data, and topographic covariates from 2020 to 2024, covering both bare soil (April–May) and growing seasons (June–August). A prediction model combining Fuzzy C-Means (FCM) clustering and Long Short-Term Memory (LSTM) networks was developed using 640 topsoil samples. Results indicate: (1) the FCM-LSTM zonal ensemble achieved optimal performance on the independent hold-out test set (R² = 0.84, RMSE = 3.20 g kg⁻¹); (2) multi-temporal data fusion effectively enhanced accuracy; compared to relying solely on bare soil data, including growing season data increased the R² of Sentinel-2 and Sentinel-1 by 0.08 and 0.03, respectively; and (3) the synergistic use of multi-temporal radar and optical data, supplemented with environmental covariates, significantly improved SOC prediction. This study demonstrates the effectiveness of integrating multi-temporal remote sensing with a zonal ensemble strategy, providing a robust methodological template for high-precision tillage management and soil fertility preservation in critical black soil regions.

69. 题目: Effects of UVC/H2O2 on dissolved organic matter derived from a cyanobacterial bloom
文章编号: N26090511
期刊: Journal of Hazardous Materials
作者: Sofia Iliakopoulou, Theodoros M Triantis, Maria Antonopoulou, Giovanni Andrea Vitale, Abzer K Pakkir Shah, Daniel Petras, Anastasia Hiskia, Triantafyllos Kaloudis
更新时间: 2026-09-05
摘要: Cyanobacterial blooms release complex metabolite mixtures, yet their degradation during water treatment remains poorly understood. This study investigates the degradation of cyanometabolite-rich natural bloom extracts using UVC/H2O2 to generate hydroxyl radicals (HO•). By applying LC-HR-MS/MS combined with computational metabolomics, we identified nine microcystins (MCs), four anabaenopeptins (APs), and sixteen microginins (MGs), proposing structures for five new congeners and two novel transformation products (TPs). UVC/H2O2 accelerated cyanopeptide degradation compared to individual control treatments. Kinetics were described by a second-order time-dependent polynomial model, reflecting matrix heterogeneity, dynamic HO• scavenging by oxidation intermediates, and H2O2 self-scavenging. Molecular networking and network annotation propagation (NAP) facilitated the detection of known MC TPs alongside new oxidative cleavage products for MGs and APs. Compositional profiling revealed distinct molecular restructuring post-treatment, characterized by decreasing nitrogen-rich peptides and a concurrent relative increase in lipids and fatty acids. Overall, this workflow provides crucial insights into HO•-driven transformation pathways within complex cyano-HAB mixtures during advanced oxidation.

70. 题目: Highly subnanoporous-basic activated biochar for enhanced removal of short-chain PFAS from drinking water
文章编号: N26090510
期刊: Chemical Engineering Journal
作者: Md Manik Mian, Jiaxin Zhu, Xiangzhe Jiang, Shubo Deng
更新时间: 2026-09-05
摘要: Activated carbon (AC) is effective for per- and polyfluoroalkyl substance (PFAS) remediation, yet the adsorption of short-chain PFAS remains a critical challenge. Hence, understanding the structure–adsorption relationship is crucial for selecting better adsorbents. Here, we prepare activated biochars with systematically controlled porosity and surface charge through physical and chemical activation to reveal the effective pore size and surface chemistry for short-chain PFAS. The results showed that short-chain PFAS uptake correlates strongly with subnanopores (0.56–0.85 nm), high point of zero charge (PZC), and low -COOH groups. The adsorption mechanism is governed by pore filling driven by electrostatic interactions arising from π-electron basicity, nitrogen, and pyrone-type oxygen functionalities. Moderate steam activation simultaneously optimized subnanopore size and PZC, whereas higher burn-off widened pores, shifting selectivity toward long-chain PFAS. Chemical activation, in contrast, reduced PZC and diminished electrostatic affinity. Surprisingly, larger granules slowed adsorption–desorption kinetics, improving PFBA uptake relative to powders. Across diverse PFAS-anion matrices, the optimized biochar achieved PFBA partitioning coefficients 5–6.5 times higher than F400 and maintained 1.0–10.6 times higher partitioning for HFPO-DA, PFHxS, and PFOA, with high recyclability and stability upon reuse. In column tests at environmentally relevant concentrations, it treated 2.9 times more water than F400 before 10% PFBA breakthrough while sustaining improved long-chain PFAS removal. By resolving the pore-size–surface charge synergy essential for short-chain PFAS capture, this work establishes design principles for low-cost adsorbents with dual short- and long-chain PFAS affinity.

71. 题目: Synergistic effects of anthropogenic and climatic factors on seasonal organic matter settling flux dynamics: lipid biomarker evidence from a shallow eutrophic lake
文章编号: N26090509
期刊: Organic Geochemistry
作者: Rupin Zhang, Yu Yang, Yong Ran
更新时间: 2026-09-05
摘要: The flux of organic matter (OM) settling in lakes is influenced by multiple environmental drivers, yet the coupled effects of anthropogenic and climatic factors on its seasonal dynamics remain inadequately quantified. To investigate the seasonal dynamics and controlling mechanisms of OM flux, settling particles were collected throughout a full year from a shallow, eutrophic urban lake (Lake Liuhuahu, south China) using a sediment trap and were analyzed for organic geochemical proxies and lipid biomarkers (n-alkanols and sterols). Results revealed significant seasonal variation in settling particle fluxes, with higher values during the wet season. Lipid biomarkers and C/N ratios indicated that the OM was predominantly derived from phytoplankton, and the flux of phytoplankton-derived OM was elevated in the wet season. Wastewater inputs, indicated by coprostanol ratios, exerted a substantial influence, particularly during the wet season. Rock-Eval parameters revealed that the settling OM was relatively fresh and well-preserved, with minimal oxidative degradation, confirming that the sediment trap record reliably captures water-column processes. Mantel tests and redundancy analysis identified wastewater discharge, air temperature, and nutrients as key drivers of the variance in OM flux. Variance partitioning analysis further demonstrated significant coupling effects among wastewater, climate, and nutrients. The interaction of sewage and climatic factors explained 13.5% of the variance in phytoplankton-derived OM, and the coupling effect of sewage, nutrients, and climate explained 8.6%. These findings highlight that the synergistic interactions of multi-source environmental factors, especially between anthropogenic inputs and climate variables, control the seasonal dynamics of OM flux. By integrating biomarker-based flux estimates with degradation state assessment, this study provides new insights into how human activities and climate change are encoded in sedimentary OM records.

72. 题目: Divergent formation pathways of soil particulate and mineral-associated organic carbon across soil depths under conservation tillage
文章编号: N26090508
期刊: Applied Soil Ecology
作者: Hong-Xuan Duan, Yu-Gang Tian, Cheng-Ze Yang, Qing Luo, Yang Liu, Zhi-Yan Hou, Rattan Lal, Yash Pal Dang, Zhi Dong, Xin Zhao, Hai-Lin Zhang
更新时间: 2026-09-05
摘要: Conservation tillage (CT) promotes soil organic carbon (SOC) sequestration by increasing residue input and enhancing physical protection. However, the biological mechanisms driving SOC fraction formation across different soil depths under CT remain poorly understood. We investigated these mechanisms using data from an 8-year field experiment in Northeast China with three treatments: rotary tillage without straw mulching (RT), no-till without straw mulching (NT), and no-till with straw mulching (NTS). We quantified SOC fractions including particulate organic carbon (POC) and mineral-associated organic carbon (MAOC), plant-derived C (PC, via lignin phenols), microbial-derived C (MC, via amino sugars), and extracellular enzyme activities. Results showed that the 0–20 cm layer was co-dominated by POC and MAOC, whereas the 20–30 cm layer was dominated by MAOC (accounting for 79–96% of SOC). Formation pathways also differed between depths: in the 0–20 cm layer, POC accumulation was primarily associated with PC accumulation, while MAOC formation involved contributions from both PC and MC. In contrast, in the 20–30 cm layer, both POC and MAOC were more closely associated with microbial-derived C. Compared with RT, NT increased PC and MC concentrations by 34% and 6%, respectively. Compared with NT, NTS further enhanced PC and MC concentrations by 35% and 73%, respectively. These percentages represent treatment comparisons averaged across the 0–30 cm soil profile, rather than layer-specific responses. Additionally, NT enhanced the activities of C- and N-acquiring enzymes, thereby accelerating residue turnover and transformation. Overall, these findings indicate that conservation tillage regulates SOC accumulation through depth-dependent and fraction-specific pathways, with plant-derived C contributing mainly to topsoil POC formation and microbial-derived C becoming more closely associated with MAOC stabilization at depth.

73. 题目: Agricultural practices reshape molecular fingerprints of dissolved organic matter in aquatic ecosystems: A case study in China's Dai Village
文章编号: N26090507
期刊: Journal of Environmental Management
作者: Yifan Cui, Jinfu Liu, Shuailong Wen, Shaojuan Du, Kyoung-Soon Jang, Ang Hu, Jianjun Wang
更新时间: 2026-09-05
摘要: Agricultural management practices significantly influence the biogeochemical cycling of dissolved organic matter (DOM) in freshwater ecosystems, yet the molecular-level signatures of DOM in conventional farming regions (CFR) versus organic farming regions (OFR) remain poorly understood. Here, an OFR with a 20-year history of organic farming and a corresponding CFR were selected to explore differences in DOM molecular characteristics and functional diversity under contrasting agricultural management regimes. We found that both CFR and OFR were dominated by CHO molecules, while CFR showed higher relative abundance of low molecular weight (<300 Da) and nitrogen-containing molecules than OFR. Unique molecules in CFR were characterized by higher proportion of lipid-like compounds, and significantly lower molecular weight, degrees of unsaturation and oxidation, while unique molecules in OFR were dominated by lignin-like compounds with higher degree of oxidation. The functional divergence and dispersion of unique molecules was significantly higher in CFR than in OFR, illustrating more convergent DOM functional traits under organic farming. Furthermore, physicochemical properties explained higher variance in DOM molecular composition in CFR (R2 = 0.92) than in OFR (R2 = 0.49), with total nitrogen and total phosphorus as dominant drivers in CFR, whereas nitrite and total organic carbon showed the highest contribution in OFR. These findings demonstrate that conventional farming promotes the accumulation of nitrogen-rich, functionally diverse DOM molecules influenced by both terrestrial inputs and autochthonous, while organic farming leads to more oxidized and recalcitrant DOM in ponds, driven primarily by terrestrial inputs.

74. 题目: Application of extracellular polymeric substances recovered from aerobic granular sludge as bio-based hydrogels for plant cultivation systems
文章编号: N26090506
期刊: Journal of Environmental Management
作者: Antonio Pescatore, Benedetta Pagliaccia, Tommaso Lotti, Claudio Lubello, Riccardo Campo, Simone Orlandini, Marco Napoli
更新时间: 2026-09-05
摘要: Wastewater treatment plants generate large amounts of excess sludge, whose management represents an environmental and economic challenge, motivating resource recovery strategies in line with European Union Directive 2024/3019. Among these, the extraction of extracellular polymeric substances (EPS) enables conversion of sludge-derived biopolymers into sustainable hydrogel materials. However, the effects of structural EPS (sEPS) on nutrient availability and plant performance remain poorly understood. This study investigated aerobic granular sludge derived sEPS as hydrogel-based substrates for in vitro seedling cultivation. Garden cress (Lepidium sativum L.) was grown in substrates containing 0, 1, 2, and 4 g TSsEPS L−1 sEPS, applied as stand-alone hydrogels (sEPS-CM) or combined with Murashige and Skoog medium, with and without sucrose (MS + sEPS-CM; MS + sEPS + S-CM). Nutrient availability, Ca/N stoichiometry, and plant responses were evaluated. In MS-based systems, increasing sEPS concentrations reduced bioavailable Ca2+ and inorganic nitrogen, inducing a shift in Ca/N stoichiometry. Germination was not affected. In stand-alone hydrogels, the best responses were observed at 1 g TSsEPS L−1, with maximum shoot and root growth and vitality, whereas 4 g TSsEPS L−1 showed inhibitory effects. Nutrient-rich systems, with increasing sEPS concentrations, reduced dry biomass, pigments, soluble sugars, and photosynthetic performance, with the strongest negative effects at 4 g TSsEPS L−1. The MS + sEPS + S system showed the highest performance, highlighting the role of carbon availability. Overall, sEPS act as structural matrices and regulators of nutrient availability. Moderate concentrations (∼1 g TSsEPS L−1) are compatible with plant development, whereas high levels induce nutrient limitation, highlighting potential as bio-based substrates for sustainable cultivation systems.

75. 题目: Palaeoenvironmental evolution and stage-dependent organic matter enrichment in the Late Permian Longtan Formation, Upper Yangtze Block, South China
文章编号: N26090505
期刊: Sedimentary Geology
作者: Hai-Feng Chen, Xin Jin, Marcello Caggiati, Ting-Cong Ren, Bo Luo, Lin-Hao Fang, Hua-Wen Cao, Yang Liu, Chang-Cheng Huang, Bin Xiao, Zi-Han Ma, Hui-Dong Yu, Hao Zou
更新时间: 2026-09-05
摘要: Middle to Late Permian marine-continental transitional successions are sensitive archives of climate, sedimentary-system change, and carbon-cycle perturbation, but remain less well constrained than coeval open-marine carbonates. Here, we investigate fine-grained sediments of the Longtan Formation at the Baoding section in the eastern Sichuan Basin, Upper Yangtze Block, South China. Stratigraphically, the Longtan Formation records an interruption of the preceding carbonate platform system and the development of a terrigenous-influenced transitional setting. We integrate organic carbon isotopes (δ13Corg), total organic carbon, total sulphur, mercury concentration, and whole-rock major and trace element data to reconstruct palaeoenvironmental evolution and organic matter enrichment. The results indicate strong source-area weathering under a warm-hot and humid climate, substantial terrigenous input, and stage-dependent changes in volcanic input, palaeosalinity, water-mass exchange, productivity, upwelling and redox conditions. Together, these variations record the stage-dependent depositional and environmental evolution of the Longtan Formation. A pronounced negative δ13Corg excursion of about 5.3‰ in the middle part of the Longtan Formation is interpreted as part of a broader Wuchiapingian carbon-cycle perturbation and provides a valuable reference for future refinement of the regional framework and assessment of its potential for global correlation. Organic matter enrichment was governed by the balance between supply and preservation, with three modes: terrigenous influence-anoxic preservation in the lower part, intermittent input-burial compensation in the middle part, and productivity-preservation coupling in the upper part. These results show how volcanic disturbance, terrigenous supply and depositional-system reorganisation jointly regulated palaeoenvironmental evolution and organic matter enrichment in a Late Permian marine-continental transitional setting.

76. 题目: Palaeoenvironmental evolution and organic matter enrichment in the Early Silurian Yangtze Foreland Basin: Tectonosequence stratigraphic insights for shale gas exploration
文章编号: N26090504
期刊: Applied Geochemistry
作者: Xinguo Li, Rui Liu, Yuxuan Wang, Junwei Pu, Hui Liu, Lu Xu, Tongtong Luo, Xiucheng Tan, Weiming Chen, Ruiying Chao
更新时间: 2026-09-05
摘要: Although large amounts of organic-rich marine shale were deposited in the foreland basin, the mechanisms governing organic matter enrichment remain debated. The Early Silurian Longmaxi shale in the Upper Yangtze Block provides critical insights into the mechanisms of organic-matter enrichment within a foreland basin. This study integrates seismic stratigraphy, sedimentology, and geochemistry to unravel the influence of tectonic and depositional dynamics on organic matter enrichment. The Longmaxi shale, deposited within a transgressive system tract, is bounded at the top by a maximum flooding surface (MFS) marked by a silty-laminated mudstone unit with a high gamma-ray peak in the lower part of a low gamma-ray response, and at the base by an angular unconformity at the Ordovician-Silurian boundary formed during forebulge migration. The Longmaxi shale consists of four parasequences, with pinch-out lines migrating northwestward toward the Chuanzhong Forebulge Uplift, reflecting westward progradation driven by high sediment flux from the Cathaysia Block. Redox-sensitive proxies (Corg/P and MoEF/UEF ratios) reveal a vertical shift from anoxic (Parasequences 1–2) to suboxic (Parasequences 3–4) conditions during the Rhuddanian sea-level rise; meanwhile, nutrient flux indicators (P and Baex concentrations) show an upward increase of primary productivity. Generally, total organic carbon (TOC) content correlates strongly with the redox-sensitive (Corg/P ratio) and sedimentation rate (Ti, Al) proxies, but weakly with the primary productivity proxy, Baex concentration. These patterns suggest that organic matter enrichment in the Early Silurian Longmaxi shale of the Upper Yangtze Block was primarily controlled by deepwater oxygen level and inorganic particle dilution. Deglaciation-driven freshwater input enhanced watermass circulation and deepwater oxygenation, thus reducing the preservation efficiency of organic matter, particularly in the foredeep adjacent to the Cathaysia Block. Additionally, although elevated sedimentation rates enhanced primary productivity via increased nutrient supply, dilution by inorganic detrital particles markedly reduced organic matter abundance in the foredeep. These findings highlight that high-quality shale gas reservoirs were most likely developed in intervals characterized by persistent anoxia and minimal detrital dilution, providing a predictive framework for sweet spot identification in foreland basin settings.

77. 题目: Soil texture regulates organic carbon sequestration via divergent accumulation pathways of plant- and microbial-derived carbon
文章编号: N26090503
期刊: Applied Soil Ecology
作者: Yiming Yun, Wenliang Yang, Xianfeng Zhang, Xiuli Xin, Xianjin Xie, Anning Zhu
更新时间: 2026-09-05
摘要: High sand content inherently restricts soil organic carbon (SOC) accumulation due to limited sorption sites, yet the specific impact of soil texture on carbon (C) sequestration remains unexplored, particularly regarding C sources, fractions, and pool sizes. Here, 35 topsoil samples (0–20 cm) spanning four textural classes along a sand-content gradient (clay loam to sand) were collected from a typical Fluvo-aquic soil region to elucidate the mechanisms of SOC sequestration regulated by texture. We determined soil physicochemical properties, SOC content and fractions, as well as plant- and microbial-derived C. Results indicated that increasing sand content significantly reduced soil nutrient concentrations and led to a sharp decline in SOC content, dropping from 12.47 ± 1.28 g kg−1 in clay loam to 5.85 ± 1.65 g kg−1 in sandy soils (P < 0.05). The SOC depletion was primarily driven by the reduction in mineral-associated organic C (MAOC, P < 0.001). Sandy texture directly reduced the retention of plant-derived C (PDC, specifically Vanillyl and Syringyl phenols), thereby primarily constraining the accumulation of easily oxidizable organic C (EOC) and driving a decline in the PDC contribution to SOC (from 31.5% to 18.7%). Meanwhile, sand-induced nutrient scarcity indirectly constrained the accumulation of microbial necromass, hindering the stabilization of fungal-dominated microbial-derived C (MDC) into MAOC despite its stable contribution (22.0%–25.3%). Ultimately, the limited SOC sequestration is attributed to the texture-regulated dual restriction on plant residue retention and microbial necromass accumulation. These findings provide a theoretical basis for enhancing the SOC sequestration potential in coarse-textured soils.

78. 题目: Grassland management pattern affects soil organic carbon content but not its mineralization on the Qinghai-Tibetan Plateau
文章编号: N26090502
期刊: Applied Soil Ecology
作者: Yizhe Peng, Jianjun Cao, Jan F Adamowski, Asim Biswas, Hong Wang, Yiyang Peng, Xiaoqing Yang, Xinhao Deng, Xiongwei Zeng
更新时间: 2026-09-05
摘要: In compliance with China's household contract responsibility system for grasslands on the Qinghai-Tibetan Plateau, grasslands are primarily managed under either the multi-household pattern (MMP) or the single-household pattern (SMP). Although the effects of these management patterns on vegetation and soil carbon have been extensively studied, their effects on soil carbon mineralization potential remain poorly tested. We conducted a 136-day laboratory incubation to compare soil carbon mineralization between MMP and SMP, integrating measurements of soil physicochemical properties, vegetation biomass, organic matter sources and stability, microbial communities, and functional genes, to identify the underlying drivers. Cumulative carbon mineralization (Ccum) did not differ significantly between MMP and SMP. Instead, Ccum varied across soil depths, with greater values in the topsoil (0–0.15 m) than the subsoil (0.15–0.30 m) under both management patterns. In the topsoil, Ccum was primarily associated with belowground biomass and lignin phenol concentrations. In contrast, subsoil Ccum was mainly explained by soil physicochemical properties and the abundance of functional genes involved in starch and lignin degradation. Within 0–0.30 m, soil physicochemical properties were the strongest direct predictor of Ccum (path coefficient = 0.58). These findings highlight that at equal stocking rates, MMP matches SMP in carbon release but boosts topsoil SOC by 17% and subsoil nitrogen retention by 29%, suggesting that MMP contributes to improved soil carbon storage and nutrient retention on the Qinghai–Tibetan Plateau.

79. 题目: Balancing benefits and risks in food waste biochar: Pyrolysis severity effects on contaminant fate, nutrient leaching, and biological safety
文章编号: N26090501
期刊: Waste Management
作者: Ojima Z Wada, Rashad Al-Gaashani, Sruthi Udayakumar, Sara Wahib, Tricia A Gomez, Tareq Al-Ansari, Khaled A Mahmoud
更新时间: 2026-09-05
摘要: Thermochemical conversion of food waste into biochar offers a compelling circular economy pathway for soil amendment, yet comprehensive safety assessments remain limited. This study assessed the stability, contaminant fate, nutrient leaching, and microbial compatibility of bone and mixed vegetable biochars pyrolyzed at 300–600 °C. Feedstock identity dominated variance in yield, ash, and carbon (η2 = 0.73–0.91), whereas temperature governed the volatile heteroatoms H, O and N (η2 = 0.44–0.74; all p < 0.001). At 600 °C, bone retained higher yield (60.3 ± 0.7 % vs 34.4 ± 0.7 %) and appreciable porosity (118.0 m2/g), whereas vegetable biochar showed negligible surface area (≤1.0 m2/g) yet preserved a carbon-rich matrix (59.5 ± 0.5 % vs 11.5 ± 1.3 % C). Vegetable biochar attained thermal stability (H/C < 0.7) by 400 °C, while bone did not cross this threshold. Bone was nutrient-dense (Ca 145,285 ± 25,963; P 73,321 ± 18,435 mg/kg), but its ions remained matrix-bound, raising leachate pH/EC only to 8.5 ± 0.18 and 235.7 ± 7.9 µS/cm versus 10.3 ± 0.08 and 1,202.5 ± 6.4 µS/cm for K-rich (25,325 ± 5,060 mg/kg) vegetable biochar, releasing far more labile ions (Na 96.4 % vs 44.8 %; p < 0.001). Mild pyrolysis (300 °C) eliminated key agrochemical and pharmaceutical contaminants (carbamazepine, pyrimethanil, o-hydroxybiphenyl) without generating EPA-priority polycyclic aromatic hydrocarbons; industrial plasticizers persisted at 600 °C, highlighting the need for upstream feedstock screening. Pyrolysis reduced dissolved organic carbon to < 10 mg/L, lowering colony counts to control levels, unlike raw bone (59-fold higher, p = 0.001). Bone biochar thus functions as a slow-release mineral scaffold, while vegetable biochar confers liming potential for acidic soils, manageable by pre-washing. Pyrolysis severity and feedstock selection are jointly critical to biochar safety.

80. 题目: Stability of stream biofilm community composition to transient shifts in dissolved organic carbon characteristics
文章编号: N26090420
期刊: Biogeosciences
作者: Oliviah Lines, Ewen Silvester, Suman Acharya, Aleicia Holland, Michael Shackleton
更新时间: 2026-09-04
摘要: . Microbial communities within biofilms are widely recognised as important contributors to ecological food webs and elemental cycles within stream systems. Yet, little is known about how these biofilm communities respond compositionally to storm-event-driven changes in dissolved organic carbon (DOC) characteristics. Alpine headwater peatland-draining streams offer a unique opportunity to investigate this response as these systems are known to export high loads of DOC during storm events, with little further upstream input. This study investigated how sub-alpine peatland-draining stream biofilm composition changed in response to storm-event-driven pulses of DOC. It was found that during the peak of each DOC pulse, the composition of DOC changed to include increased contributions of organic acids, protein-like substances and microbially derived DOC. Despite this change in DOC composition, the composition of most biofilm microbial communities did not significantly shift following each pulse; rather, differences in biofilm community composition appeared to be more closely linked to peatland stream site. The findings of this study suggest biofilm microbial communities maintain compositional stability following short-term rapid changes in stream water chemistry, and that site-specific environmental factors may be more important in determining biofilm microbial community composition in sub-alpine headwater peatland-draining streams.