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21. 题目: Hydrogen-rich syngas production via biomass pyrolysis catalyzed by iron co-loaded with biochar and aluminum smelting fly ash: Tar formation and component characteristics
文章编号: N26101810
期刊: Journal of Environmental Management
作者: Xueqin Li, Zhiwei Wang, Peng Liu, Yan Lu, Huina Zhu, Qun Wang, Gaofeng Chen, Tingzhou Lei
更新时间: 2026-10-18
摘要: Biomass pyrolysis for hydrogen production is generally regarded as a crucial technological pathway to achieve the carbon neutrality goals, whereas the corresponding system efficiency and environmental friendliness are significantly constrained by the generation of tar byproducts. In this study, the iron-based carbon-aluminum (Fe/Carbon-AWA) composite catalyst was prepared via the hydrothermal carbonization method using corn straw (CS) as the carbon-based precursor, and activated aluminum smelting ash (AWA) as the support. Besides. its catalytic effect on hydrogen production performance was systematically investigated, and the intrinsic relationship between tar conversion and hydrogen yield was further elaborated. The results demonstrate that when the Fe loading reaches 10%, the catalyst exhibits optimal catalytic activity with a hydrogen yield of 64.36 mL/g-biomass, a hydrogen selectivity of 39.96%. Meanwhile, the total gas yield of 161.06 mL/g-biomass can be achieved, accounting for 43.77% of the total product yield, whereas the liquid yield decreases to 36.44%. The full-component analysis of tar indicates that the light tar fractions are primarily composed of oxygenated compounds. In contrast, the heavy tar fractions are dominated by polycyclic aromatic hydrocarbons (PAHs) with a pyrolysis weight loss rate of only 54.24%. This limited pyrolytic reactivity represents the critical bottleneck in the tar conversion. It reveals that the Fe/Carbon-AWA catalyst can remarkably promote the cracking and conversion of refractory heavy tar components, and thereby the chemical energy stored in tar is partially converted into the hydrogen-rich syngas, resulting in an energy recovery efficiency of 17.72% and a carbon efficiency of 8.02%. Accordingly, this comprehensive strategy with the combination of waste-to-waste catalyst design and full-component analysis of tar was established. This work provides a feasible pathway for the synergistic development of biomass-based hydrogen production and waste valorization, which contributes to the efficient process integration and systematic optimization of biomass energy systems.

22. 题目: Agronomic Viability of Landfill Leachate-derived, Humic Extract as an Agricultural Fertilizer
文章编号: N26101809
期刊: Water, Air, & Soil Pollution
作者: Roberto Martins Nazareth, Arthur de Pontes Coelho Jorge, Gustavo Souza Lima Sant’Anna, Luiz Alberto da Silva Rodrigues Pinto, Franz Guillermo Munoz Ibanez, Everaldo Zonta, Marcos Gervasio Pereira, Irene da Silva Coelho, Nivaldo Schultz
更新时间: 2026-10-18
摘要: The objective of this study was to evaluate the agronomic viability of a humic extract (HE), obtained from landfill leachate, as an agricultural fertilizer. A sugarcane crop ( Saccharum sp., var. RB867515’) was grown in pots in a greenhouse using samples of an Argissolo Vermelho-Amarelo (Ultisol) and a Latossolo Vermelho (Oxisol). The treatments consisted of soaking sugarcane nodes with buds in either distilled water or 80% (v/v) HE solution for an hour, followed by foliar and/or soil application of 90% (v/v) HE, or mineral fertilization, or both. After 10 months of greenhouse cultivation, dry mass accumulation, nutrient and metal contents in plant dry mass, soil chemical attributes, and soil bacterial diversity were evaluated. HE promoted sugarcane growth and dry mass accumulation compared with that in control, with performance similar to that under mineral fertilization, particularly in the treatment in which the nodes with buds were soaked in distilled water and subsequently received foliar and soil applications of 90% (v/v) HE. No heavy metals (Cr, Cd, and Pb) were detected in plant tissues and in soil, and soil bacterial diversity was not affected by HE application. The data presented herein suggests preliminary evidence that HE may serve as an agricultural fertilizer under greenhouse conditions, although additional field-scale studies are required to confirm its efficacy and safety.

23. 题目: Ice Converts Phenols into Persistent Mineral-Bound Polymers
文章编号: N26101808
期刊: Environmental Science & Technology
作者: Yang Rong, Tao Luo, Tao Chen, Tra My Bui Thi, Khalil Hanna, Jean-François Boily
更新时间: 2026-10-18
摘要: Freezing fundamentally alters how minerals transform dissolved phenols in cold environments. As water freezes, solutes are excluded from the crystal lattice and concentrated into microscopic pockets of unfrozen liquid, creating reaction conditions far more extreme than those of bulk solution. Here, we compare catechol oxidation on a key soil manganese oxide under freeze–thaw versus room-temperature conditions. Freezing redirects products from soluble humic-like substances to thermally stable, mineral-bound polymers. Freeze–thaw conditions removed over 50% of dissolved organic carbon within 24 h compared to less than 10% at room temperature, with solid-phase carbon increasing over 50-fold. The attenuation of the effect with increasing salinity is consistent with freeze-concentration as a key driver and indicates that the pathway should be strongest in freshwater and low-salinity frozen environments. Freeze–thaw conditions also converted preformed soluble products into mineral-bound forms, demonstrating that the process operates on a range of substrates. These findings reveal an unrecognized abiotic carbon stabilization pathway that could operate when microbial decomposition is suppressed by freezing with direct implications for carbon dynamics in permafrost and seasonally frozen environments.

24. 题目: Effect of nitrogen fertilisation under different land use on the total and labile organic carbon content in a calcareous chernozem under temperate climate
文章编号: N26101807
期刊: Plant and Soil
作者: Márk Rékási, Nikolett Uzinger, Péter Csontos, Orsolya Szécsy, Péter Ragályi
更新时间: 2026-10-18
摘要: Background and Aims Land management has a significant impact on soil organic carbon (SOC) and its labile fraction, measured as permanganate-oxidizable carbon (POXC). However, the impact of nitrogen (N) fertilisation on these properties is not always consistent. This study investigated the effect of land use and N fertilisation, plant biomass and diversity on SOC and POXC. Methods Samples were taken from a cropland on chernozem soil after 17 and 27 years of ploughing and 20 years after switching to grassland under different N fertilisation (0, 100, 200 and 300 kg ha −1 ). Results Ten years of ploughing reduced both SOC and POXC content, but grassland management reversed the decrement. N fertilisation mitigated SOC decrease by 90% that was 471 kg ha −1 year −1 in the control treatment. Under grassland management N fertilisation reduced SOC restoration rate from 425 (control) to 164 kg ha −1 year −1 (200 kg N ha −1 ). Fertilisation caused inconsistent changes in POXC over the sampling times but average POXC values ​​increased from 352 to 399 mg kg −1 at control and highest N dose, respectively. Under grassland management, the influence of biomass on SOC and POXC outweighed that of biodiversity. The relationship between POXC and SOC has been attenuated with increasing N fertilisation rates. Conclusion Nitrogen fertilisation was effective tool in reducing carbon loss during arable farming but hindered SOC restoration under grassland. SOC was a better indicator of cultivation and N fertilisation than POXC. Land use was more decisive for the POXC level than N fertilisation.

25. 题目: Molecular transformation of dissolved black carbon during photobleaching and its enhanced role in goethite-mediated 17α-ethinylestradiol anaerobic biotransformation
文章编号: N26101806
期刊: Journal of Hazardous Materials
作者: Feiyuan Liu, Weiqing Ma, Zhicheng Liao, Chaochao Lai, Xiunan Cai, Huan He, Bin Huang, Xuejun Pan
更新时间: 2026-10-18
摘要: Dissolved black carbon (DBC) is an important component of dissolved organic matter, which undergoes continuous photobleaching in the sunlit surface water. The resulting photobleached DBC (P-DBC) can subsequently be transported across the sediment-water interface into sediments rich in minerals and microbes, thereby regulating the transformation of organic contaminants. This study investigated photobleaching-induced molecular transformation of DBC and the mechanism of P-DBC in goethite-mediated 17α-ethinylestradiol (EE2) anaerobic biotransformation. The results showed that photobleaching promoted the oxidation and decarbonization of DBC, driving its molecular composition toward a higher oxidation state and lower energy density. Intensity and H content were the key molecular features governing the photochemical reactivity of DBC. P-DBC was enriched in oxygen-containing functional groups that could enhance electron transfer with goethite. Additionally, the higher bioavailability of P‑DBC enriched aromatic‑degrading bacteria. Species associated with iron reduction and organic matter transformation in the presence of goethite were increased. As a result, P-DBC combined with goethite significantly promoted the anaerobic biotransformation of EE2, achieving a removal efficiency of 73.0%. EE2 transformation involved de-ethynylation and decarboxylation to yield more oxygenated products, contrasting with co‑metabolism alone. These findings provide new mechanistic insights into the natural attenuation of estrogens in iron-rich aquatic environments.

26. 题目: Biochar granulation and particle size influence hydrological performance of green roof substrates
文章编号: N26101805
期刊: Journal of Environmental Management
作者: Wenxi Liao, Jennifer A P Drake, Sean C Thomas
更新时间: 2026-10-18
摘要: Green roofs are increasingly implemented in cities to improve stormwater management and provide additional ecosystem services. Biochar, a carbon-rich material derived from pyrolyzed biomass, has emerged as a promising substrate additive to improve hydrological performance of green roofs. Biochar granulation and particle size modification have been suggested as effective approaches to mitigate erosion losses but research on the effects of biochar post-processing on hydrological performance remains scarce, and data on fundamental hydraulic properties of biochar-amended green roof substrates is entirely lacking. We investigated how biochar granulation and particle size influence surface and pore characteristics and hydraulic properties of green roof substrates in laboratory experiments. Granulated biochars exhibited collapsed surface morphology and pore structure, resulting in consistent hydrological responses across particle size ranges, likely due to the homogeneous structure formed during granulation. In contrast, unprocessed biochars showed a significant increase in Brunauer-Emmett-Teller (BET) specific surface area and pore volume with decreasing particle size. The amendment of granulated biochars improved substrate field capacity, suggesting potential enhancement of stormwater retention. The addition of fine (0.5–1 mm) and intermediate-sized (2–2.8 mm) unprocessed biochars also increased plant available water. Although reduced saturated hydraulic conductivity associated with fine unprocessed biochars may improve green roof detention capacity, fine biochar particle size may increase erosion losses and periodic waterlogging. We conclude that the application of either granulated biochar or intermediate-sized unprocessed biochar may provide a balanced enhancement of stormwater retention and detention capacities, as well as improved plant available water in green roof systems.

27. 题目: Reducing PFAS Mobility and Plant Uptake in Agricultural Soils via Biochar Amendment
文章编号: N26101804
期刊: Environmental Science & Technology
作者: Jiahui Hu, Zheng Li, Desmond Hanan, Michael P Schmidt, Abasiofiok M Ibekwe, Daniel J Ashworth
更新时间: 2026-10-18
摘要: Biochar amendment represents a promising in situ strategy for per- and polyfluoroalkyl substances (PFAS) mitigation, yet its performance under realistic field conditions remains poorly understood. Here, we evaluated PFAS fate in soil–plant–leachate systems under irrigation-water- and biosolids-derived contamination settings. Pinewood biochar (PBC) significantly (P = 0.05) reduced PFAS leaching and plant uptake more so than biosolids-derived biochar (BBC), driven by its higher point of zero charge (PZC), C/H and C/O ratios, and specific surface area, with the strongest mitigation observed for PFHxS and PFOA. Air oxidation and iron oxide modification of PBC further suppressed short-chain PFAS accumulation in plants. Among the tested materials, air-oxidized PBC exhibited the highest mitigation efficiency (ME), reducing leaf bioconcentration factors (BCFs) of PFHxS and PFOA by 1328.5-fold and 285.3-fold, respectively, and suppressing perfluorobutanoic acid (PFBA) accumulation by 150.8-fold, attributable to enhanced surface area, electrostatic attraction, and hydrogen-bonding interactions. Dissolved organic matter (DOM) released from biosolids increased the mobility of PFBA, PFBS, PFOA, and PFHxS while reducing the bioavailability and translocation of PFNA and PFOS. Collectively, this work demonstrates that PFAS mitigation by biochar is governed by molecular structures, input pathways, and DOM interactions, providing mechanistic insight for targeted biochar deployment in PFAS-impacted agroecosystems.

28. 题目: Covariation of DOM molecular characteristics and bacterial carbon metabolism potential along a reservoir-agricultural river nutrient gradient
文章编号: N26101803
期刊: Environmental Geochemistry and Health
作者: Yue Jiang, Hongying Jiang, Yanhua Xie, Tianliang Zheng
更新时间: 2026-10-18
摘要: Agricultural nutrient loading is associated with variation in dissolved organic matter (DOM) composition and microbial communities across reservoir-agricultural river continuums, yet the covariation among nutrient conditions, DOM molecular heterogeneity, and bacterial metabolic potential remains insufficiently understood. This study integrated optical spectroscopy, ultrahigh-resolution mass spectrometry, nitrate dual-isotope tracing, end-member mixing analysis (EMMA), 16S rRNA sequencing, and metagenomic functional profiling to characterize DOM sources and composition and their associations with bacterial communities in a typical reservoir-agricultural river continuum. Our results showed that nitrogen and phosphorus enrichment within agricultural river reaches systematically rearranges DOM source apportionment, with relative abundance of humic-like components (C1, C3) rising alongside elevated abundances of heteroatomic molecular formulas (CHOS, CHONS) relative to oligotrophic reservoirs. Nutrient loading reshaped DOM via exogenous input of heteroatom-rich anthropogenic organics and boosted in-situ microbial humification. EMMA modeling further indicated that anthropogenic sources contributed 37.9% to riverine DOM. Principal coordinates analysis showed that reservoir-river community differentiation coincided with nutrient and fluorescent DOM gradients. Reservoir samples were dominated by Acinetobacter, Exiguobacterium, and Clade_III and showed higher relative abundances of several genes associated with carbohydrate and aromatic compound degradation. In contrast, river communities featured humic-adapted genera (Mycobacterium, hgcl_clade, Limnohabitans, and unclassified_Sporichthyaceae) and showed higher relative abundances of genes associated with lipid utilization and terrestrial-polymer degradation. This study highlighted coordinated spatial variation in nutrient conditions, DOM characteristics, bacterial community composition, and genomic carbon metabolism potential across the reservoir-agricultural river continuum, supplying theoretical guidance for pollution control and carbon cycling regulation in anthropogenic-disturbed inland water catchments.

29. 题目: Soil-Dependent Microbial Metabolic Strategies Shape Microplastic-Induced Molecular Transformation of Dissolved Organic Matter
文章编号: N26101802
期刊: ACS Environmental Au
作者: Lijia Lu, Zhuoran Duan, Jia Shi, Wenqing Zeng, Boya Li, Jingzhi Wang, Si Li, Meng Zhao, Yuanze Sun, Jie Wang
更新时间: 2026-10-18
摘要: Microplastic contamination fundamentally alters terrestrial carbon cycling, yet the mechanisms linking polymer exposure to the formula-level transformation of dissolved organic matter (DOM) remain poorly resolved. Here, we integrate ultrahigh-resolution mass spectrometry with genome-resolved metagenomics to track dissolved organic matter turnover in contrasting agricultural soils exposed to conventional and biodegradable microplastics. In the two contrasting soils tested, DOM molecular trajectories diverged strongly with the soil background. Biodegradable microplastics were associated with extensive loss of putative lignin-like precursor formulas in a nutrient-limited loess soil. This loss coincided with highly expanded, precursor-dominated paired mass distance networks of up to 3882 edges and 2448 nodes, in which nodes present assigned molecular formulas and edges represent mass-difference-inferred putative transformations. Overwhelming negative microbial correlations characterized by 5247 negative versus 801 positive links were observed. Functionally, this pattern co-occurred with a community-wide shift toward resource-acquisition strategies, with normalized traits increasing by up to 205%. Conversely, in carbon-rich black soil, microplastics promoted selective molecular reworking and net product accumulation. Paired mass distance networks remained compact with approximately 1000 nodes, and metagenome-assembled genome networks were dominated by positive associations at 72.2%. These more stable dynamics were accompanied by a microbial shift toward growth-yield traits. By proposing a conceptual soil-polymer-microbiome framework derived from two contrasting soils, our findings caution against assuming that biodegradable microplastics are universally ecologically benign and suggest that they may intensify turnover of native organic matter in resource-limited soils, a possibility that requires direct testing with isotope-based approaches.

30. 题目: Molecular Size Mediates Sunlight Effects on the Biodegradation of Aquatic Dissolved Organic Matter: Insights from the Reservoir Wetland and Incubation Experiment
文章编号: N26101801
期刊: Environmental Science & Technology
作者: Peng Zhou, Long Tian, Shian Song, Muhammad Saboor Siddique, Kurt Friese, Peter Herzsprung, Andrew J Tanentzap, Nigel Graham, Wenzheng Yu
更新时间: 2026-10-18
摘要: Dissolved organic matter (DOM) in aquatic ecosystems is crucial to climate, water quality, and water sanitation. However, little is known about how photochemical and biological processes interact to regulate the cycling of DOM in water environments. Here, we investigate the photobiochemical processing of different molecular weight (MW) fractions of aquatic DOM by incubating them with microbes in the dark and light/dark cycling environments via microcosm experiments. Light exposure has distinct effects on the medium (MMW; 1–20 kDa) and low (LMW; <1 kDa) MW fractions and can enrich photoautotrophic bacteria and taxa that could benefit the utilization of aromatic compounds. The decay of the MMW fraction displays the highest light sensitivity, with light increasing the net depletion of tannin- and condensed aromatic-like molecules and production of labile substrates (e.g., protein-like) from photoautotrophic bacteria. In contrast, the net decomposition of the LMW fraction is the least promoted by light exposure, as light induces the net production of complex aromatic molecules that are more persistent. Our findings provide new insights into the photobiochemical and molecular mechanisms underlying the ecological impacts of aquatic DOM and their relevance for wider processes.

31. 题目: Microbial deamination of peptides and proteins as a source of persistent marine dissolved organic matter
文章编号: N26101713
期刊: Limnology and Oceanography Letters
作者: Pauline L Martinot, Cédric G Fichot, Hussain Abdulla, Karl Kaiser
更新时间: 2026-10-17
摘要: Refractory dissolved organic nitrogen is a major component of the ocean's nitrogen pool, yet the mechanisms producing and preserving it remain poorly understood. Here, we show that deaminated peptides (DAPs), derived from microbial processing of proteinaceous material, are ubiquitous across oxygenated marine environments—from productive coastal waters to the oligotrophic ocean—and persist from surface to bathypelagic depths. Using ultrahigh‐resolution mass spectrometry and a curated peptide database, we detected candidate DAP formulas with substantial contributions from hydrophobic amino‐acid residues and recurrent compositions containing diaminopimelic acid ( Dapa ), consistent with a contribution of bacterial cell‐wall material. Laboratory incubations demonstrate substrate control on DAP composition: simple‐substrate treatments yield narrow, source‐specific amino acid profiles, whereas complex substrates produce broader assemblages resembling field observations. Together, widespread DAP occurrence and substrate‐dependent production in microbial incubations support peptide deamination as a potential microbial nitrogen pump pathway, linking labile surface nitrogen to persistent storage in the ocean interior.

32. 题目: Dual-phase plastic derivatives: Phase-specific photochemical behaviors and impacts on aquatic carbon
文章编号: N26101712
期刊: Water Research
作者: Jingyi Gu, Tingting Cai, Yi Liang, Pei Na, Weilin Huang, Zhi Dang, Chen Yang
更新时间: 2026-10-17
摘要: Aquatic carbon cycling is increasingly perturbed by exogenous organic carbon from plastic derivatives. These derivatives form a dual-phase system, comprising particulate nano-plastics (NPs, reaching 108 particles/mL) and truly dissolved fractions (accounting for ˃60% of the mass), with the potential to redistribute carbon between fast and slow cycling pools. However, the phase-specific contributions to photochemical processes and carbon flow remain poorly defined. Here, combining ultrafiltration and quantitative carbon tracking, we elucidate their intrinsic phase specificity. Morphologically, PP-NPs exist as rough, irregular fragments, whereas PS-NPs exhibit highly regular, smooth spherical structures. Spectroscopic analyses revealed that PP derivatives exhibit weak, dissolved-phase-dominated absorption/fluorescence activities with strong inter-phase structural heterogeneity. Conversely, PS derivatives maintain robust and consistent dual-phase optical properties driven by cross-phase chemical homology. The photoreactivity and carbon fates of both derivatives are synergistically governed by phase- and polymer-specific mechanisms. The dissolved fraction serves as the core precursor driving primary photoactive species (3DOM*) generation, whereas particulate NPs provide solid-liquid interfaces that amplify the yields of secondary reactive species (1O2 and •OH) by 1.54- to 2.24-fold. Notably, PS-NPs, whose surfaces are highly enriched with reactive sites (Δ=0.25 µmolₑ⁻ mg-1 C), can deeply intervene in short-term carbon flows via dual pathways of photon competition and carbon replenishment. Nevertheless, the presence of particulate NPs does not alter the ultimate upper limit of mineralization; rather, they construct an optical shield that decelerates the mid-term rate of carbon phase transformation. By resolving phase specificity via quantitative carbon tracking, this study provides a mechanistic framework for integrating plastic carbon into aquatic biogeochemical models and evaluating its ecological consequences.

33. 题目: Biochar–Straw Interaction Drives Soil Carbon Accrual by Modulating Microbial Metabolic Pathways
文章编号: N26101711
期刊: Environmental Science & Technology
作者: Rui Ma, Yifeng Zhang, Xiaodong Zheng, Xiang Li, Lan Wei, Lianxi Huang, Shuai Ding, Qimei Lin, Yu Luo, Zhongzhen Liu
更新时间: 2026-10-17
摘要: Straw and biochar additions can enhance long-term carbon storage, yet how their interactions regulate carbon mineralization and allocation remains unclear. We conducted a 360-day microcosm incubation employing a reciprocal 13C-labeling design that paired 13C-labeled straw with unlabeled biochar and unlabeled straw with 13C-labeled biochar and used single-cell Raman spectroscopy and 13C-labeled cell metagenomics. At day 360, biochar reduced cumulative straw-derived 13CO2 from 1391 to 1199 mg C kg–1 soil, while increasing straw-C allocation to fulvic acid (FA) and humic acid (HA) fractions. This shift was associated with enrichment of bacterial taxa such as Chitinophagales and increased abundance of genes involved in phospholipid metabolism, the phenylacetyl-CoA pathway, and potential polyphenol-related processing. Conversely, straw increased biochar-derived dissolved organic carbon from 1.5 to 5.5 mg C kg–1 soil and cumulative 13CO2 release from 17 to 23 mg C kg–1 soil, increasing FA and HA allocation. This shift was associated with the enrichment of genes involved in oxidative degradation, membrane transport (for substrate uptake), exopolysaccharide (EPS) formation, and quinone biosynthesis. Overall, the biochar–straw interaction redirected exogenous carbon from rapid mineralization toward humic substance associated soil organic matter fractions, thereby enhancing soil carbon accrual.

34. 题目: Carbonate rock weathering substantially promotes soil microbial-derived carbon accumulation
文章编号: N26101710
期刊: National Science Review
作者: Peilei Hu, Juan Li, Wei Zhang, Ji Liu, Josep Peñuelas, Jordi Sardans, Lin Xu, Xinyu Hou, Dan Xiao, Jie Zhao, Xunyang He, Li Tang, Pengpeng Duan, Jun Xiao, Tiangang Tang, Hongsong Chen, Ji Chen, Yuanhe Yang, Jørgen Eivind Olesen, Kelin Wang
更新时间: 2026-10-17
摘要: Microbial-derived carbon (necromass) is crucial for long-term soil organic carbon (SOC) persistence, yet how carbonate rock weathering regulates its accumulation remains unresolved, despite the global prevalence and rapid weathering of carbonate rocks. Using global synthesis, regional sampling, and microcosms, we tested how carbonate rock weathering affects microbial-derived carbon. Globally, karst soils contained 43.4% more amino sugars and 57.6% more SOC than non-karst soils. Regionally, karst soils had 19.3% higher SOC-normalized amino sugars, 57.8% larger mineral-associated amino sugars, and more oxidized lignin signatures. Within karst soils, weathering rate was the strongest predictor of microbial necromass, and calcium fractions were associated with mineral-associated amino sugars. In microcosms, carbonate rock addition increased soil pH and calcium, shifted enzyme allocation toward oxidative processing of chemically complex native SOC, potentially facilitating microbial necromass formation. Carbonate rock addition also increased incorporation of 13C-labelled labile carbon into microbial necromass by 22–71%. Our findings identify carbonate rock weathering as a geogenic control linking microbial necromass formation with calcium-associated stabilization, highlighting the potential to leverage this weathering pathway to enhance SOC persistence.

35. 题目: Lower soil organic carbon mineralization and temperature sensitivity along a freeze-thaw erosion gradient in permafrost soils
文章编号: N26101709
期刊: Catena
作者: Qian Xu, Changhai Tan, Hongan Pan, Xinshu Zhu, Zanpin Xing, Yongcui Deng, Yongqin Liu
更新时间: 2026-10-17
摘要: Freeze-thaw erosion (FTE) is widespread in permafrost regions, yet its effects on soil organic carbon (SOC) dynamics remain unclear. Here, we investigated SOC fractions, physicochemical properties, microbial biomass and community composition, SOC-degradation functional genes, SOC mineralization rates and their temperature sensitivity (Q10) in permafrost soils with and without FTE on the Qinghai-Tibetan Plateau (QTP). Compared with no erosion soils, FTE soils exhibited markedly lower SOC, particulate organic carbon (POC), and mineral-associated organic carbon (MAOC), indicating reduced soil carbon pools. The Q10 of SOC mineralization was significantly lower in FTE soils (mean = 3.00) than in no erosion soils (mean = 7.14), reflecting a dampened microbial respiratory response to warming. FTE also reshaped microbial community structure and altered microbial functional potential. Variation in SOC mineralization and Q10 was associated with soil carbon characteristics and specific microbial properties, suggesting their potential roles in SOC responses to FTE. Moreover, these responses varied with slope position, highlighting the importance of topography in mediating carbon redistribution and microbial responses under FTE. Overall, our findings show that FTE is associated with reduced SOC mineralization and temperature sensitivity, together with concurrent changes in soil carbon characteristics and microbial properties, providing new insights into SOC dynamics in degrading permafrost ecosystems.

36. 题目: Prebiotic organic compounds in asteroid Bennu and Ryugu reflect divergent parent body histories
文章编号: N26101708
期刊: Geochimica et Cosmochimica Acta
作者: Angel Mojarro, José C Aponte, Daniel P Glavin, Jamie E Elsila, Jason P Dworkin, Harold C Connolly
更新时间: 2026-10-17
摘要: The return of pristine samples from carbonaceous asteroids Ryugu by JAXA’s Hayabusa2 mission and Bennu by NASA’s OSIRIS-REx mission has enabled the direct comparative study of prebiotic organic compounds across the two primitive bodies. Using pyrolysis, thermochemolysis, and one-pot derivatization coupled to gas chromatography-triple quadrupole-mass spectrometry, we analyzed free volatile, insoluble, and soluble organic matter in a Ryugu aggregate and compared results to a Bennu aggregate and stones of interest. Pyrolysis of the Ryugu sample revealed polycyclic aromatic hydrocarbons, their alkylated homologues, and sulfur-, oxygen-, and nitrogen-bearing heterocyclic aromatic compounds consistent with aqueous alteration of the parent body. One-pot derivatization of the Ryugu aggregate yielded only tentative detections of β-alanine and 2,4-diaminopyrimidine. This is in contrast to the 14 proteinogenic α-amino acids and five canonical nucleobases previously detected across Bennu samples using the same technique. Thermochemolysis of the Ryugu sample revealed limited methylated derivatives while Bennu samples did not yield compounds above the procedural blank. The sparse thermochemolysis detections in samples from both asteroids are notable given that diverse methylated derivatives have been reported from the Orguiel (CI1) and Murchison (CM2) meteorites. We interpret these results as most likely originating from reagent-mineral interactions suppressing TMAH yields. Overall, contrasting organic inventories reflect divergent-parent body histories. Results from the Ryugu samples are consistent with a CI1-like classification, displaying increased alkylation of insoluble organic matter alongside depleted soluble organic matter abundances. In contrast, Bennu preserves heterogeneous organic signatures across stones recording multiple distinct alteration episodes. The presence of prebiotic molecules including amino acids and nucleobases across both asteroids further highlights the significance of carbonaceous bodies in contributing the chemical building blocks of life throughout the early Solar System.

37. 题目: Decoupled transport pathways and source materials of black carbon in the Pearl River Estuary and the North Yellow Sea
文章编号: N26101707
期刊: Marine Pollution Bulletin
作者: Min Liu, Yan Li
更新时间: 2026-10-17
摘要: Black carbon (BC) buried in marginal sea sediments represents a significant global carbon sink, yet the relative contributions of different transport pathways and source materials under varying climatic and emission regimes remain poorly constrained. In this study, we analyzed BC content, BC/TOC ratio, stable carbon isotopes (δ13CBC), and sediment grain size in surface sediments from two contrasting Chinese marginal seas: the subtropical Pearl River Estuary (PRE) and the temperate North Yellow Sea (NYS). Using a Bayesian mixing model (MixSIAR), we apportioned BC sources along two dimensions: geographic transport pathway and specific source material. BC concentration ranges overlapped widely, yet PRE had a higher mean than NYS, with distinct controls. In the energetic PRE, grain size sorting drove a clear east-west zonation. In the muddy NYS, this sorting was regionally masked by atmospheric deposition of coal combustion BC at nearshore stations. Pathway apportionment revealed two distinct receiving modes: the open PRE was dominated by marine-proximal 13C-enriched pathway (52.8%) against a uniform atmospheric background (27.2%), whereas the NYS acted as a steady-state sink dominated by terrestrial inputs (riverine: 34.5%; atmospheric: 38.4%). In contrast, source-material apportionment was highly consistent across both regions, following the order: fossil fuel combustion (∼45%) > biomass burning (∼35%) > rock weathering (∼20%). This decoupling, regionally divergent pathways but nationally convergent source materials, arises because BC transport is governed by local physical environments, while its composition reflects larger-scale emission patterns. Our findings clarify BC source–sink processes in Chinese marginal seas and provide scientific support for coordinated atmosphere–river–ocean pollution control.

38. 题目: Aggregate size regulates soil carbon priming through divergent microbial C[sbnd]N acquisition strategies
文章编号: N26101706
期刊: Applied Soil Ecology
作者: Shuaiwen Zhang, Zhiguo Li, Peng Chen, Xinxin Jing, Luping Ye, Ziyan Li, Chenhao Lyu, Yi Liu
更新时间: 2026-10-17
摘要: Soil aggregates create heterogeneous microenvironments that influence soil organic carbon (SOC) turnover and microbial communities. However, how aggregate size regulates priming effects (PE) through microbial life-history strategies and CN acquisition pathways remains unclear. We examined PE dynamics across macroaggregates (>2000 μm, MA), mesoaggregates (250–2000 μm, ME), microaggregates ( ME > MI, with MI showing a near-zero or slightly negative tendency under 25 °C + 0.1% EOM. In MA, positive correlations of PE rate with ΔDOC and ΔDN, coupled with balanced C- and N-acquiring enzyme responses, suggested co-metabolic decomposition of native SOC. In contrast, MI showed a negative correlation between PE rate and ΔDN and stronger relative investment in N-acquiring enzymes, suggesting an N-acquisition-constrained priming response rather than classical nitrogen mining. These findings suggest that aggregate size controls PE by shaping SOC accessibility, microbial r/K strategies, and CN acquisition pathways. Resource-rich MA and ME favor r-strategist-associated co-metabolism and stronger positive PE. In contrast, mineral-protected MI suggested enhanced microbial N-acquisition demand, but limited SOC accessibility constrained its translation into strong SOC priming.

39. 题目: Autotrophic respiration's higher sensitivity moderates soil organic carbon balance along precipitation gradients in saline wetlands
文章编号: N26101705
期刊: Catena
作者: Xinge Li, Wenbo Zhu, Lianqi Zhu, Weimin Song, Peiguang Li, Xiaojie Wang, Guangxuan Han
更新时间: 2026-10-17
摘要: Intensified precipitation variability profoundly affects soil carbon cycling in saline wetlands by altering soil salinity and moisture, particularly soil respiration (SR), the largest source of atmospheric CO2 emissions. However, whether autotrophic (SRa) and heterotrophic (SRh) respiration differing in substrate sources and biological processes, respond differently to precipitation change remains unclear. Furthermore, how their sensitivity modulates the soil organic carbon (SOC) balance is also poorly understood. To address this, a seven-year precipitation manipulation experiment with five treatments: (−60%, −40%, 0%, +40%, and + 60% of ambient precipitation) was conducted in the Yellow River Delta wetlands. The results revealed a positive asymmetric response of both SRa and SRh along the precipitation gradient, with larger increases under wet conditions than decreases under dry conditions. Exponential response coefficients derived from precipitation–respiration regressions indicated that SRa exhibited significantly greater sensitivity to precipitation change than SRh. Structural equation modeling revealed that changes in SRa and SRh were primarily driven by soil electrical conductivity, plant biomass (TB), and microbial biomass (MBC), with the greater sensitivity of TB compared to MBC explaining the higher responsiveness of SRa. Notably, SOC significantly increased along the precipitation gradient, and integrating these respiration responses with concurrent gross ecosystem production data from the same site indicated that enhanced plant derived carbon inputs outpaced the moderate increase in SRh, shifting the net balance toward SOC accumulation. Collectively, our results demonstrate that the higher sensitivity of SRa than SRh moderates SOC balance along precipitation gradients in saline wetland. The observations emphasize the significance of incorporating component specific respiratory sensitivity into carbon cycle models for accurate predictions of SOC dynamics under future precipitation scenarios.

40. 题目: Variation of dissolved organic nitrogen in full-scale wastewater treatment revealed by HRMS coupled with hydrogen/deuterium isotope labeling
文章编号: N26101704
期刊: Water Research
作者: Han Su, Yuwei Xie, Zhantu Ye, Lixue Liu, Yuyao Zhang, Mingbao Feng
更新时间: 2026-10-17
摘要: Dissolved organic nitrogen (DON) is an important nitrogenous fraction of wastewater effluent dissolved organic matter (DOM), with implications for eutrophication and nitrogenous disinfection byproduct formation. However, the molecular variation of DON, including amino-containing compounds, remains insufficiently elucidated across treatment trains. Herein, DOM and DON were characterized along a full-scale domestic wastewater treatment train using high-resolution mass spectrometry (HRMS). At the same time, amino-containing compounds were analyzed using HRMS coupled with hydrogen/deuterium isotope labeling. The results revealed that DON was a major and chemically distinct fraction of DOM, with lower molecular weight but greater unsaturation and aromaticity, indicating a more refractory molecular signature. Treatment evidently redistributed the occurrence patterns of DOM and DON, mainly through attenuation of lipid-like components and the increasing prominence of lignin/CRAM-like components. Adjacent-unit analysis showed that DON was jointly reshaped by attenuation and regeneration rather than monotonically removed. The front anaerobic-anoxic-oxic (AAO) biological treatment constrained DON but left a more recalcitrant residual profile. Membrane bioreactor (MBR)-moving bed biofilm reactor (MBBR) ultimately extended the AAO trend toward greater carbon-skeleton unsaturation and aromaticity, driven mainly by MBBR. Terminal disinfection only partially moderated this trend. Isotope labeling showed that amino-containing features persisted throughout treatment and were reshaped mainly by MBR-MBBR. Noticeably, MBBR increased their level and altered primary/secondary amine-like distributions before disinfection. These findings demonstrate that effective DON control should be evaluated by considering not only bulk parameters, but also the internal structure and functional-group characteristics of residual DON.