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141. 题目: Biomarker δ 13 C values record consistent savanna vegetation and variable alkalinity of Lake Olduvai during Pleistocene wet/dry cycles
文章编号: N25123101
期刊: Proceedings of the National Academy of Sciences of the United States of America
作者: Kelsey E Doiron, Devon E Colcord, Andrea M Shilling, Jackson K Njau, Ian G Stanistreet, Harald Stollhofen, Kathy D Schick, Nicholas P Toth, Simon C Brassell
更新时间: 2025-12-31
摘要: Climate records for the early Pleistocene in eastern Africa aid reconstruction of the ecology and landscapes occupied by hominins. Environmental changes associated with alternating wet/dry cycles during this critical interval in hominin evolution are recorded in isotopic profiles from lake sediments from Olduvai Gorge. The Olduvai Gorge Coring Project targeted the depocenter of Paleolake Olduvai, recovering a stratigraphic succession between the Bed I Basalt (~1.90 Ma) and Tuff IF (~1.80 Ma) datums that span hominin fossil horizons in nearby outcrops. Lacustrine claystones from the lower part of this interval are characterized by high C org (avg. 2.5 %). They display variations in δ 13 C org reflecting temporal changes in organic matter (OM) sources. Stratigraphic profiles for n -alkane δ 13 C values derived from plant waxes are consistent throughout wet/dry cycles indicating stability in savanna vegetation, refuting evidence for increased C 4 grasses during drier intervals. δ 13 C values for n -alkanes derived from aquatic macrophytes and for algal biomarkers increase during drier episodes, reflecting use of bicarbonate as a carbon source triggered by enhanced lake alkalinity. δ 13 C org profiles reflect variations in inputs of terrestrial vs. aquatic OM during wet/dry cycles, which are mirrored by δ 13 C values for hop-17(21)-ene derived from heterotrophic bacteria utilizing sedimentary OM. The δ 13 C records from Paleolake Olduvai sediments show temporal changes in OM sources rather than shifts in the proportion of C 3 and C 4 vegetation, indicating that precession-driven climate cycles primarily affected lake environments and associated aquatic resources. Thus, intervals of high climate variability did not necessarily cause changes in savanna vegetation affecting hominin habitats.

142. 题目: Biochar mitigates soil–rice accumulation of highly bioavailable heavy metals from atmospheric deposition
文章编号: N25123007
期刊: Frontiers in Environmental Science
作者: Tuantuan Fan, Ang Liu, Chenglian Feng, Zhenfei Yan, Weiying Feng, Fengchang Wu
更新时间: 2025-12-30
摘要: Little is known regarding the uptake of heavy metal(loid)s (HMs) by crops from atmospheric deposition. In this study, we examined the uptake and transport of HMs (copper, zinc, arsenic, cadmium, and lead) in rice plants through both root and foliar pathways, and the reduction of HMs in rice resulting from soil biochar applications. Our findings indicate that HMs from dust and rainfall were more mobile and bioavailable than those from slag, significantly affecting the soluble and exchangeable fractions of HMs in the soil, soil solution, and fractions detected by the diffusive gradients in thin films (DGT) technique. Rice plants exhibited a preference for absorbing atmospherically deposited HMs through both foliar and root pathways; however, the efficiency of HM uptake and translocation rates via direct foliar uptake was lower than that of root uptake from the soil. The application of biochar was found to decrease HM (Cu, Zn, Pb, and Cd) concentrations in soil mobile fractions, soil solutions, and DGT extractions, with the exception of As; this demonstrates an effective method to mitigate HM accumulation in rice. This study highlights the high risk of crop contamination in areas with high atmospheric HM loads and suggests that reducing atmospheric HM deposition and implementing soil remediation can mitigate ecological risks.

143. 题目: Dissolved Organic Matter Modulates Concentrations and Bacterial Preferences of Organophosphate Esters and Phthalates
文章编号: N25123006
期刊: Environmental Science & Technology
作者: Tuantuan Fan, Ang Liu, Chenglian Feng, Zhenfei Yan, Weiying Feng, Fengchang Wu
更新时间: 2025-12-30
摘要: Organophosphate esters (OPEs) and phthalates (PAEs) are pervasive emerging pollutants in water environments. In natural circumstances, the concentrations and behaviors of the OPEs and PAEs are inevitably influenced by various environmental factors, but the driving mechanisms behind these are still unclear. This study focused on the main tributary of the Yangtze River basin: Chishui River. It quantified the contents and sources of OPEs and PAEs and integrated DOM and microbial characteristics to specifically analyze the key driving factors influencing pollutant levels. The results showed that the concentration ranges of OPEs and PAEs from Chishui River were 8.92 × 10²–1.37 × 10³ and 39.6–1.04 × 10³ ng/L in water and 1.85 × 10³–3.63 × 10³ and 1.10 × 10²–1.43 × 10⁴ ng/g dry weight in sediment. TEP, DBEP, and DMEP were the main components requiring prioritized attention. These pollutants mainly originate from domestic waste and industrial plastics. The levels of the OPEs and PAEs were regulated by DOM adsorption and microbial degradation, respectively. Protein-like fluorophore at E_x/E_m: 275/342 nm and FI jointly verified the wastewater source of TBEP. a253/a203 demonstrated potential for monitoring the concentration of TCrP. Tolerant Exiguobacterium exhibited potential for degrading PAEs. Optical signatures of the DOM served as potential tracers for monitoring the OPEs in environmental matrices. These provide new insights into the risk assessment and fate of emerging pollutants in the natural environment.

144. 题目: Performance of novel media-based aquaponics under stress of different antibiotics: role of biochar and zero-valent iron
文章编号: N25123005
期刊: Journal of Hazardous Materials
作者: Muhammad Tanveer, Chengkai Fu, Linlan Zhuang, Yanhui Zhao, Doinglin Wang, Peihan Yu, Yiqiao Zhang, Zhen Hu
更新时间: 2025-12-30
摘要: Antibiotics are emerging pollutants that adversely affect microbial activity, disrupt nitrogen cycling, and reduce overall system performance in aquaponic systems. This study assessed the performance of media-based aquaponic systems amended with biochar mixed with zero-valent iron (BC/ZVI) under treatments with oxytetracycline (BZ-OTC), sulfadiazine (BZ-SDZ), and amoxicillin (BZ-AMX). Results demonstrated that the BZ-SDZ consistently outperformed the others by mitigating the harmful effects of sulfadiazine, achieving >99% antibiotic removal, producing the highest spinach biomass (25.40 ±3.68 g), promoting the greatest fish growth (24.11 ± 0.44 g) and minimizing nitrous oxide (N₂O) emissions. These benefits are attributed to ZVI-driven redox reactions degrading residual SDZ and biochar’s adsorption capacity reducing antibiotic bioavailability to plants and microbes. In contrast, the BZ-OTC showed moderate improvements, while BZ-AMX exhibited the least efficacy. Overall, BC/ZVI media enhanced nutrient use efficiency, system stability, and microbial diversity under antibiotic stress, providing a reliable strategy for sustainable aquaponic production in contaminated environment.

145. 题目: Biochar mitigates soil–rice accumulation of highly bioavailable heavy metals from atmospheric deposition
文章编号: N25123004
期刊: Frontiers in Environmental Science
作者: Zhaoqin Huang, Buyun Du, Ting Sun, Dongliang Ji
更新时间: 2025-12-30
摘要: Little is known regarding the uptake of heavy metal(loid)s (HMs) by crops from atmospheric deposition. In this study, we examined the uptake and transport of HMs (copper, zinc, arsenic, cadmium, and lead) in rice plants through both root and foliar pathways, and the reduction of HMs in rice resulting from soil biochar applications. Our findings indicate that HMs from dust and rainfall were more mobile and bioavailable than those from slag, significantly affecting the soluble and exchangeable fractions of HMs in the soil, soil solution, and fractions detected by the diffusive gradients in thin films (DGT) technique. Rice plants exhibited a preference for absorbing atmospherically deposited HMs through both foliar and root pathways; however, the efficiency of HM uptake and translocation rates via direct foliar uptake was lower than that of root uptake from the soil. The application of biochar was found to decrease HM (Cu, Zn, Pb, and Cd) concentrations in soil mobile fractions, soil solutions, and DGT extractions, with the exception of As; this demonstrates an effective method to mitigate HM accumulation in rice. This study highlights the high risk of crop contamination in areas with high atmospheric HM loads and suggests that reducing atmospheric HM deposition and implementing soil remediation can mitigate ecological risks.

146. 题目: Variability of Particulate Organic Carbon Stock in the South China Sea With Reference to Profile Structures
文章编号: N25123003
期刊: Geophysical Research Letters
作者: Teng Li, Yan Bai, Xianqiang He, Bangyi Tao, Xuan Zhang, Fang Gong, Yifan Zhang, Xuchen Jin, Chunfang Zhang, Zhihong Wang
更新时间: 2025-12-30
摘要: Accurate characterization of particulate organic carbon (POC) stock is essential for understanding regional biological pump processes, yet the roles of vertical structure and integration depth in regulating POC stock variability remain unclear in marginal seas. Using a performance-evaluated 3D POC data set, we assessed POC stock changes in the South China Sea. Column-mean POC covaries tightly with surface POC (R > 0.9) in both the euphotic zone and the upper 100 m. From 2003 to 2023, POC in the upper 100 m showed a basin-wide decline (−0.1 mg·m⁻³·y⁻¹). For euphotic-zone POC stock, vertical structure accounts for only ∼30% of its variability, whereas euphotic depth exerts dominant control, driving a summertime maximum and a positive changing rate (3.68 mg·m⁻²·y⁻¹) in 2003–2023. These non-steady-state stock changes highlight the need to jointly evaluate POC production, storage, and export when assessing local biological carbon pump dynamics.

147. 题目: Insights of Big Data and Machine Learning on the Depositional Environment and Organic Matter Enrichment of the Wufeng-Longmaxi Shales
文章编号: N25123002
期刊: ACS Earth and Space Chemistry
作者: Qihui Shi, Zhaodong Xi, Yidan Ding, Gary G Lash, Shuheng Tang
更新时间: 2025-12-30
摘要: Shale organic matter (OM) enrichment plays a critical role in evaluating the future prospects of shale gas worldwide. The Ordovician-Silurian transition represents a critical interval notable for extensive deposits of organic-rich shale formations. Despite this, the underlying factors controlling OM enrichment during this interval, particularly in the Wufeng-Longmaxi (WF-LMX) shale, need comprehensive reevaluation. Our study compiles major and trace element concentrations for 1376 samples and TOC values for 3143 samples from the WF-LMX shale in South China to define quantitative thresholds for redox environment and paleo-productivity. Paleoenvironmental characteristics associated with the deposition of shales containing varying OM abundances (TOC <2%, 2–4%, and >4%) were clarified. Random Forest (RF) and Artificial Neural Network (ANN) models were applied to identify the primary factors controlling OM enrichment of the WF-LMX succession. Results of this work show that MoEF, UEF, VEF, and CrEF values of 10, 10, 1.5, and 1.5, respectively, represent the threshold for anoxic conditions during shale deposition. SiO2(exc), P/Ti, and Babio values of approximately 30%, 0.2, and 1000 ppm, respectively, signify high paleo-productivity. RF and ANN results suggest that redox environment and paleo-productivity as the foremost influences on OM accumulation, followed by paleoclimate. Organic-rich shales (Type-a, TOC > 4%) were primarily deposited under warm and humid climate conditions. Enhanced nutrient supply promoted elevated productivity and established anoxic bottom conditions that facilitated OM preservation. Type-c shales (TOC < 2%) accumulated under low-moderate productivity and oxygenated bottom conditions, leading to extensive degradation and dilution of organic matter. Type-b shales (TOC = 2–4%) exhibit intermediate characteristics between Type-a and Type-c. This study offers new perspectives on OM enrichment mechanisms in the WF-LMX shale succession and provides a theoretical basis for shale gas exploration within this stratigraphic interval.

148. 题目: Mechanistic insights into organic acid-enhanced polycyclic aromatic hydrocarbon release from soil: Disruption of metal cation bridges and charge-assisted hydrogen bonds
文章编号: N25123001
期刊: Environmental Research
作者: Shuting Wei, Yue Yuan, Weifeng Chen, Jinzhi Ni, Huiying Zhang, Meiyu Yang, Ran Wei
更新时间: 2025-12-30
摘要: While low molecular weight organic acids (LMWOAs) are commonly used to enhance the dissolution and bioavailability of polycyclic aromatic hydrocarbons (PAHs) in soils, a comprehensive mechanistic framework is lacking. In this study, four representative organic acids (formic, acetic, citric, and oxalic acids) were systematically evaluated to their efficacy in promoting PAH desorption from a long-term contaminated soil, with particular emphasis on elucidating the governing mechanisms and environmental implications. The results demonstrated that these organic acids increased the release of PAHs and dissolved organic carbon (DOC) by 1.17-1.90 fold and 1.12-17.39 fold, respectively, compared to the NaCl control. The ratio of desorbed PAHs per unit of DOC followed the order: acetic acid > formic acid ≫ citric acid ≥ oxalic acid. Citric and oxalic acids solubilized significantly more Fe3+ and Al3+ (bridging cations between minerals and soil organic matter, SOM) than formic and acetic acids, thereby releasing larger amounts of dissolved organic matter (DOM) with relatively high molecular weights. However, additional solubilization of Fe3+ and Al3+ had negligible effects of on PAH desorption. The dominant mechanisms governing PAH desorption included Ca2+ dissolution and the disruption of negative charge-assisted hydrogen bonds, (-)CAHB, within SOM (including both intermolecular and intramolecular linkages). From the perspective of maintaining soil fertility and mitigating global climate change, formic/acetic acids outperform citric/oxalic acids in PAH desorption. The key advantage is that they release less biodegradable DOM, which reduces the risk of increased CO2 emissions and helps preserve SOM.

149. 题目: Unraveling the enhanced electrocatalytic deactivation of dilute antibiotics on metal-free superhydrophobic porous biochar
文章编号: N25122912
期刊: Separation and Purification Technology
作者: Wei Fan, Linpiao Cheng, Chunyang Dan, Shengjun Wang, Shenbin Zheng, Huimin Sui, Yun Zhang, Guangming Jiang, Wenyang Fu, Liang Ao, Xiaoshu Lv
更新时间: 2025-12-29
摘要: Electrocatalytic hydrodechlorination (ECHD) represents a sustainable strategy for deactivating chlorinated antibiotics through hydrogenolysis of Csingle bondCl bonds. However, its widespread application is hindered by the scarcity of cost-effective catalyst, as well as their insufficient efficiency in treating trace antibiotics. Herein, a porous superhydrophobic biochar was fabricated from rice straw via a stepwise process of thermal pyrolysis, acidic etching and chemical reduction, which demonstrates an exceptional adsorption capacity of 575.0 mg g−1 for florfenicol (FLO) and a remarkable mass activity of 1.1 mg min−1 g−1 in ECHD of 20.0 mg L−1 FLO at −0.6 V. This performance not only exceeds reported biochars produced with fewer processing steps, but also surpasses several metal-based catalysts. Our biochar was further confirmed competent in degrading more dilute FLO (2 mg L−1) in contaminated lake water. Mechanistic investigations reveal that the outstanding ECHD performance of the biochar stems from its superhydrophobic and porous property, promoting adsorptive enrichment of trace antibiotics. In contrast, the carbon defects and oxygen-containing groups introduced during thermal pyrolysis impede electron transfer between the biochars and pollutants, due to unfavorable orbital occupancy, elevated work function and increased surface polarity within biochar. These findings emphasize the necessity of chemical reduction to remove these interfering moieties, while confirming the promise of porous and superhydrophobic biochars as sustainable catalysts for antibiotic-contaminated water remediation.

150. 题目: Efficient removal of polystyrene microplastics using a novel clay-biochar composite: An insight into effect of pH, DOM and interfering ions
文章编号: N25122911
期刊: Separation and Purification Technology
作者: Tauseef Ahmad, Sumaira Gul, Tariq Mehmood, Philippe Zinck, Fei Liu, Eric D van Hullebusch, Yating Luo, Hui Lu, Peng Licheng
更新时间: 2025-12-29
摘要: The widespread accumulation of microplastics (MPs) in aquatic environments highlights the urgent need for effective remediation strategies. Biochar-based adsorption has emerged as a sustainable and cost-efficient approach. In this study, a novel montmorillonite-biochar composite (MBC) was synthesized from bamboo biomass to enhance polystyrene microplastics (PS-MPs) removal efficiency. The synthesized adsorbents were characterized using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). These characterization techniques confirmed the successful loading of montmorillonite onto the biochar surface. The results showed that MBC exhibited a markedly higher removal efficiency (90 %) compared to pristine biochar (BC), which achieved 78 % under the same experimental conditions. SEM analysis revealed three key immobilization mechanisms—’Stuck,’ ‘Trapped,’ and ‘Entangled’—affecting PS-MPs retention on the adsorbent surface. Dissolved organic matter (humic acid), pH, and Ca2+ concentration significantly impacted the adsorption capacity, with optimal adsorption occurring at pH 6. The maximum adsorption capacities of BC and MBC were 45.78 and 55.66 mg/g, respectively. The adsorption mechanisms of BC were mainly governed by van der Waals forces and hydrophobic interactions, whereas MBC additionally benefited from electrostatic and π–π interactions. The adsorption kinetics fitted well with pseudo-first-order and pseudo-second-order models (R2 > 0.94), and isotherm fitting revealed compatibility with Langmuir and Freundlich models (R2 > 0.93). These results demonstrate that MBC is a promising material for efficient MPs removal and support the development of low-cost, environmentally friendly water treatment technologies suitable for mitigating plastic pollution in aquatic ecosystems.

151. 题目: Explainable data-driven spatial predictions of soil organic carbon at the national level
文章编号: N25122910
期刊: Science of the Total Environment
作者: Azamat Suleymanov, Evgeny Abakumov, Igor Savin
更新时间: 2025-12-29
摘要: Accurate spatial modeling of soil organic carbon (SOC) and interpretation of the results are crucial worldwide. In this study, we performed national-scale SOC mapping in Russia with a focus on model interpretability under Shapley values technique with its geovisual analysis. Also, we compared Random Forest (RF) models with a different set of covariates and basic hyperparameter tuning. Results revealed that neither the number of covariates nor the tuning significantly affected the model performance, with the best model achieving an RMSE = 70.03 g/kg and an R² = 0.39. The generated map confirms that northern Russia holds immense SOC levels, primarily driven by the presence of organic soils and peatlands, but overestimated the lowest SOC levels in the south. Shapley value analysis revealed that both biotic and abiotic variables showed complex and non-linear relationships with SOC. Mean annual temperature and precipitation contributed positively to predictions in the north, with a sharply positive effect observed specifically within the 270–280 K (−3.15 to +6.85 °C) range and >500 mm, respectively. Furthermore, higher variability in land surface temperature and elevations below 250 m were identified as key factors promoting SOC accumulation, delineating the carbon-rich Siberian lowlands. The spatial pattern of Shapley values for the major covariates demonstrated a positive contribution to SOC prediction mainly in the northern regions. Notably, the boundary between the positive and negative contributions of some climatic variables coincided with the boundary between Dfb (warm-summer humid continental) and Dfc (subarctic) climatic zones. This study provides a critical baseline for Russia's soil carbon inventory and underscores the value of interpretable machine learning for unravelling the environmental drivers of major Earth carbon sink.

152. 题目: Organic carbon cycling in hemipelagic and turbidite sediments of Santa Monica Basin, California Borderland
文章编号: N25122909
期刊: Geochimica et Cosmochimica Acta
作者: David J Burdige, Tomoko Komada
更新时间: 2025-12-29
摘要: We examined carbon cycling in the upper ∼ 1.2 m of sediments from the center of Santa Monica Basin (SMB) CA using a reaction-transport model applied to dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) concentration and isotope signature profiles (δ13C and Δ14C). The sediments here consist of ∼ 20 cm of laminated hemipelagic sediment and a ∼ 1 m thick layer containing sand-silt turbidites. Linear solute profiles of inorganic reactants or products of anoxic remineralization in the turbidite layer suggest that this is largely a diffusion-dominated zone. Model results support this interpretation showing that remineralization in the turbidite sediments is ∼ 2 % of that in the upper hemipelagic sediments. Benthic fluxes of DOC from SMB sediments contain both “labile” and “refractory” components, as has also been observed in studies of nearby Santa Barbara Basin (SBB) sediments. When the two sets of results are compared, there appears to be a larger flux of labile DOC from SMB versus SBB sediments. Differences in the nature of iron redox cycling in the surface sediments of the two basins may explain these observations. If the relative amounts of refractory DOC in the total benthic DOC fluxes from SMB and SBB sediments are representative of continental margin sediments globally, then the integrated flux of sediment-derived refractory DOC represents ∼ 3–160 % of the refractory DOC added to the oceans. At its high end, this suggests that some of the refractory DOC which leaves these anoxic sediments as a benthic flux may be remineralized in oxic marine waters on time scales shorter than ocean mixing. Model results from SMB and SBB provide evidence that sediments are a potential source of both refractory and pre-aged (14C-depleted) DOC to the oceans. Specifically, the benthic flux of refractory DOC from both basins includes components with Δ14C signatures that range from around −300‰ to −400‰, or even lower. This occurs because some fraction of the refractory DOC produced in the sediments (and ultimately added to the water column as a benthic flux) is either “pre-aged” in the sediments based on its pre-depositional OM source, or is produced by remineralization of less reactive OM whose 14C content decreases with sediment age and burial. At the same time, SMB and SBB sediments are not representative, in general, of continental margin and coastal sediments, and the broader relevance of the benthic flux of 14C depleted DOC (and its impact on the radiocarbon signature of deep ocean DOC) will require further studies in a wider range of sedimentary environments.

153. 题目: A Bibliometric‐Based Review of Biochar for Salt‐Affected Soil Restoration: Mapping Research Trends and Future Directions
文章编号: N25122908
期刊: Land Degradation & Development
作者: Juciane Vieira de Assis Freire, Darliane Cristina Soares de Souza, Larissa Fernandes da Silva, Poliana Pinheiro da Silva, Thiago Henrique Freire de Oliveira, Eulene Francisco da Silva, Bruno Caio Chaves Fernandes, Adriano Erique de Oliveira Lima, Bárbara Samartini Queiroz Alves, Daniel Valadão Silva, José Cleiton Sousa dos Santos, Frederico Ribeiro do Carmo, Rafael Leandro Fernandes Melo
更新时间: 2025-12-29
摘要: In recent years, biochar has been studied for its range of applications. Recognized by the IPCC as a key Carbon Dioxide Removal (CDR) strategy, it also stands out as an important tool for reclaiming degraded lands, including vast global areas affected by salinity, such as those in China, India, and Australia. This study explores the application of biochar in these salt‐affected soils through a bibliometric analysis and literature review. The research used the Web of Science database, from which 42,928 articles were initially identified. After careful keyword selection, the number was refined to 326 relevant publications. The analysis mapped the contributions of countries, institutions, and authors. Keyword analysis identified five thematic clusters, confirming that research is predominantly focused on soil application. The results show that China leads scientific production on this topic. However, a significant knowledge gap persists regarding the main research fronts in this field. The most relevant journals, such as Science of the Total Environment and Agronomy‐Basel , are the primary platforms for these studies. The overview highlights biochar's main applications in remediating saline soils, while addressing advances and challenges. The study also suggests future research directions, such as improving production technologies, adapting biochar to different soil types, and assessing long‐term environmental impacts.

154. 题目: Contributions of benthic microalgal biofilms to sediment organic carbon stocks across a salt marsh gradient
文章编号: N25122907
期刊: Limnology and Oceanography
作者: Graham J C Underwood, Nicola J D Slee, Jessica C J Underwood, Christopher I D Underwood, James L Pinckney
更新时间: 2025-12-29
摘要: Benthic microalgal (BMA) communities contribute significantly to food webs, nutrient cycling, and carbon flows in intertidal habitats. However, the contribution of BMA to saltmarsh carbon stocks (“blue carbon”) is unclear. BMA and sediment total organic carbon (TOC) stocks were measured in an east coast American Atlantic saltmarsh, revealing key relationships between biofilm biomass, carbohydrate, and carbon content. BMA biomass (chlorophyll a ) was highest in Sporobolus stands and mudflat habitats, with diatoms the dominant algal group, and cyanobacteria more important in upper saltmarsh sites. Habitat‐specific differences in biofilm properties (biomass, carbohydrates, photopigments, near‐infrared spectra) corresponded to differences in overall contributions to sediment TOC. Carbohydrates contributed between 8% and 23% of sediment TOC, with the highest levels in Sporobolus and mudflat habitats. BMA biomass and colloidal carbohydrate were significantly correlated, except on lower shore sandflats. The greatest relative contribution of colloidal carbohydrate to %TOC was in upper marsh and tidal channel habitats (1%). Mudflats had the highest %TOC (up to 5% dry weight), but TOC stocks (2000 g C m −2 to a depth of 10 cm) were highest in Sporobolus habitats. A modeling approach, based on LIDAR and sediment measures, determined a BMA carbon contribution of 1.3–8% of sediment TOC, with the lowest values in Sporobolus and mudflat habitats. Upscaling from m 2 , incorporating habitat heterogeneity, gave median values of 14–16 t TOC ha −1 for the North Inlet Estuary saltmarshes, of which BMA contributed 0.06–0.08 t C ha −1 . This approach could permit BMA contributions to blue carbon to be estimated across other saltmarshes.

155. 题目: Microbial decomposition of Sargassum enhances recalcitrant dissolved organic carbon production and sedimentary carbon sequestration
文章编号: N25122906
期刊: Journal of Environmental Management
作者: Lili Xu, Bilin Jin, Ligong Zou, Yee Jun Tham, Yufeng Yang, Qing Wang
更新时间: 2025-12-29
摘要: Seaweeds are fundamental components and primary producers in marine ecosystems, and their growth and decay significantly influence environmental conditions and microbial community structure. However, considerable debate persists regarding whether seaweed decomposition enhances marine carbon sequestration, and the role of microbes in seaweed degradation remains unclear. This study examined the degradation process of Sargassum under controlled laboratory conditions to assess its potential for carbon sequestration. After 240 days of decomposition on the sediment surface, the dissolved organic carbon (DOC) in the overlying water stabilized, with approximately 24.79 ± 11.42 % having been transformed into recalcitrant dissolved organic carbon (RDOC), accounting for about 1.37 ± 0.12 % of the initial seaweed detrital carbon. The decomposition rate of Sargassum buried in sediments was significantly slower (p < 0.05), leading to an estimated 22.15 ± 3.49 % increase in carbon sequestration. The RDOC released by Sargassum accounted for approximately 10.91 %–11.78 % of the total RDOC molecules. Microbial degradation of Sargassum produced RDOC molecules enriched in CHOS and CHONS, with larger molecular mass, higher double bond equivalents (DBE), and greater aromaticity indices (AI), all consistent with recalcitrant molecular properties. Microbial succession during Sargassum degradation enriched chemoheterotrophic and fermentative taxa, thereby driving the conversion of labile DOC (LDOC) to RDOC. These results demonstrate that Sargassum decay enhances RDOC accumulation and sedimentary carbon sequestration. Therefore, a future management strategy for senescing Sargassum could involve burying some in nearshore sediments to increase carbon storage and mitigate pollution from decomposition in coastal environments.

156. 题目: Mitigating antibiotic resistance and pathogenic risk in spiramycin fermentation residue composting via integrated acidic hydrothermal pretreatment and biochar amendment
文章编号: N25122905
期刊: Journal of Environmental Chemical Engineering
作者: Quancheng Shu, Jinzhi Sun, Xiaoyong Yang, Yucan Liu, Yanxiang Zhang, Jing Ding, Lijuan Lan, Picheng Gong, Zheng Liu, Hongwei Sun, Gang Wang
更新时间: 2025-12-29
摘要: This study employed a metagenomic approach to systematically investigate the effects of biochar amendment following acidic hydrothermal treatment (AHT) on the composting of spiramycin fermentation residue (SFR). Biochar accelerated organic matter degradation and significantly reshaped the microbial community structure through increased diversity and promotion of Pseudomonadota dominance during the maturation stage. Biochar also effectively suppressed pathogen proliferation and reduced the abundance of virulence factor genes (VFGs). Maximum reductions in antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) reached 20.8% and 40.4%, respectively, with particularly pronounced suppression of high-risk ARGs. Mantel analysis indicated significant correlations between vancomycin and sulfonamide resistance genes and plasmids, transposases, and IS91, suggesting that the dissemination of these ARGs is primarily mediated by horizontal gene transfer via MGEs. Partial least squares path modeling further demonstrated that ARG dissemination was mainly driven by MGEs and regulated by microbial community structure, while biochar effectively mitigated ARG propagation by improving environmental conditions and inhibiting MGE activity. Functional annotations revealed that biochar enhanced metabolic pathways related to carbon and nutrient cycling. Overall, the combination of AHT pretreatment and biochar addition facilitates efficient resource recovery and safe disposal of SFR, offering a viable strategy for producing environmentally benign organic fertilizers.

157. 题目: N-doped biochar as a promising peracetic acid activator for sulfamethoxazole removal: Performance and mechanism
文章编号: N25122904
期刊: Chemical Engineering Journal
作者: Zhuoran Li, Lu Han, Ran Wang, Jiaxuan Yu, Siqi Wang, Kaige Li, Qun Jiang, Jie Liu, Jianhua Qu, Ying Zhang
更新时间: 2025-12-29
摘要: Eco-friendly and low-price catalysts for activating peracetic acid (PAA) are crucial to promote its application in pollutants removal. Herein, nitrogen doping with different nitrogen source masses was employed to regulate the internal structure of waste pomegranate peel-derived biochar (BC), thereby enhancing its activation ability for PAA to remove sulfamethoxazole (SMX). In NBC/PAA system, with the dosage of 300 mg/L NBC and 3 mM PAA, the excellent removal efficiency (97.5 %) of SMX was achieved within 30 min, and kobs was 10.9 times that of the BC/PAA system. Unlike previously reported PAA-based advanced oxidation process with •OH and R-O• as the primary reactive species, non-free radical pathway induced by electron transfer and 1O2 was evidenced to act the dominant role, and the role of free radical (•OH and R-O•) pathway was secondary for SMX removal. The graphitized structure (i.e., graphitic N and C-C/C=C) was proved to be involved in PAA activation, which was regarded as electron shuttler to mediate the electron transfer from SMX to PAA. High SMX removal efficiency was realized in extensive pH range and the interference of coexisting ions. Moreover, NBC/PAA system was proved to process minimum environmental impact by life cycle assessment (LCA). In conclusion, the discoveries of this work offer the valuable development and broad application prospects of N-doped BC for PAA activation to remove antibiotic.

158. 题目: Green manure incorporation as a solution to synergistically improve crop yields and soil organic carbon sequestration
文章编号: N25122903
期刊: Journal of Cleaner Production
作者: Lei Fan, Liqian Sun, Xiaotian Mi, Yiting Fan, Yufan Huang, Gang He
更新时间: 2025-12-29
摘要: Planting and incorporating green manure has been widely used worldwide due to the benefits of improving soil quality and crop yields. However, a comprehensive assessment of the effects of planting and incorporating green manures on soil properties and crop production is still lacking. Here we conducted a meta-analysis to determine the effects of green manure planting and incorporation on soil nitrate-N leaching, soil water, soil properties, SOC sequestration, and crop yield in wheat, maize, rice, and tobacco. Results showed that planting and incorporating green manure reduced soil nitrate-N leaching during its growing season by 44 %, and reduced the soil water storage in the 0–200 cm soil layers before sowing and at harvest of the following crop by 11 % and 5 %, respectively. Incorporating green manure increased soil total nitrogen, soil available phosphorus, soil available potassium, and SOC sequestration rate by 13 %, 8 %, 8 %, and 64 % in the 0–20 cm soil layer, respectively. As a result, green manure incorporation increased the mean yield of the following season by 12 %, with maize yields significantly higher than those of rice and tobacco. Over the past six decades, the area harvested for green manure has increased substantially worldwide, playing an important role in sustainable crop production. Scientific management of green manure will therefore be a key strategy to achieve a win-win situation for both food security and environmental protection.

159. 题目: Controls of landscape and hydrological dynamics on DOM sources and distribution in a typical basin of the three Gorges Reservoir
文章编号: N25122902
期刊: Journal of Hydrology
作者: Yuying Liu, Xiaojun Zhao, Xinzhi Hu, Chenchen Wang, Shan Yi, Yanxue Jiang, Jinsong Guo, Guangyu Zhu
更新时间: 2025-12-29
摘要: Dissolved organic matter (DOM) plays a critical role in pollution source tracking and basin management. In the Three Gorges Reservoir (TGR) areas, severe anthropogenic disturbances and substantial seasonal hydrological fluctuations, resulting in strong spatiotemporal variability in DOM. However, although these disturbance factors are widely recognized, their mechanistic pathways and dominant processes remain poorly understood. Therefore, we selected a typical hilly small basin with mixed land use in the TGRs as the study area. Using fluorescence spectroscopy combined with Mantel tests, redundancy analysis, and structural equation modeling, we investigated the spatiotemporal distribution characteristics of DOM and systematically assess the direct and indirect effects of land use and landscape patterns (LULP), as well as seasonal hydrological conditions, on DOM characteristics. Results showed that during the high-flow period, DOM was dominated by terrestrial sources, whereas microbial contributions were relatively weak. LULP primarily influenced DOM indirectly by modulating nutrient loads in the water. Seasonal fluctuations in DOM composition and sources were largely attributable to the direct dilution effects of rainfall. Notably, the spatial correlation between DOM characteristics and landscape metrics was more pronounced during the low-flow period. This pattern may reflect the spatial homogenization of terrestrial components under high-flow conditions, whereas reduced ecological flows during the low-flow period enhance their spatial heterogeneity. Based on these findings, we propose a targeted DOM regulation and water quality management strategy for small basins, emphasizing land use optimization, enhanced landscape configuration, and spatiotemporal coordination of pollution control. This integrated approach provides a scientific foundation for refined basin management.

160. 题目: Biochar single addition improves sunflower water-deficit tolerance by optimizing chlorophyll a fluorescence and seed nutritional quality
文章编号: N25122901
期刊: Plant and Soil
作者: Ruxin Zhang, Zhongyi Qu, Wei Yang, Dongliang Zhang, Shaopan Xia, Junjie Li, Enliang Ren
更新时间: 2025-12-29
摘要: Aim Biochar application is a promising strategy to mitigate water deficiency impacts on crops, yet its synergistic effects with deficit irrigation (DI) on photosynthetic fluorescence performance and seed nutritional quality and their coupling mechanism remain poorly understood. Methods A two-year field experiment with factorial combinations of irrigation regimes [full irrigation (FI, 100% ETc) vs. deficit irrigation (DI, 60% ETc)] and biochar amendments (0, 15, 30 t ha⁻1, denoted as B0, B15, B30) were conducted in the semiarid region of China. Results High-dose biochar (B30) effectively alleviated water-stortage induced photoinhibition in Photosystem II. Compared to DI without biochar amendment, the DI + B30 treatment enhanced F0/Fm by 33.0% and Fv/F0 by 7.9%, while simultaneously reducing the inactivation of Photosystem II reaction centers as evidenced by a 6.4% decrease in Vi during 2022. Particularly noteworthy was the biochar-mediated amplification of J—phase fluorescence intensity (reflecting the accumulation of reduced primary electron acceptor QA⁻) during the O—J transition. Concurrent with these photosynthetic improvements, B30 application under DI conditions significantly elevated seed nutritional quality parameters: crude fat content increased by 5.0%, protein content by 9.6%, and proline accumulation by 6.9%. Structural equation modeling further deciphered the hierarchical relationships among key parameters, identifying Fv/F0 (total effect = 0.70), leaf area index (0.60), plant height (0.58) and aboveground biomass (0.56), as primary drivers of seed quality enhancement (R2 = 0.73). Conclusion Our findings demonstrate that the biochar—DI synergy optimizes photosynthetic resilience and nutritional value, providing a water-carbon management framework for arid farmland.