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81. 题目: Divergent patterns of organic carbon burial between alpine lakes in the context of climate warming and intensified atmospheric nitrogen deposition
文章编号: N26040502
期刊: Palaeogeography, Palaeoclimatology, Palaeoecology
作者: Yongdong Zhang, Caini Yang, Kunshan Bao, Lingyang Kong
更新时间: 2026-04-05
摘要: Alpine lakes play a crucial role in lake organic carbon (OC) burial studies because these lakes are devoid of direct human interventions in their catchments and thus allow us to evaluate how climate change and atmospheric deposition shape lake OC burial; however, this topic remains inadequately addressed to date. Here, we employed a paleolimnological approach in two adjacent alpine lakes (Lakes Cuoqia and Wodi Co) from Yunnan Province, SW China, to delineate OC burial patterns in the context of climate warming and intensified atmospheric nitrogen (N) deposition. In Lake Cuoqia, the high TOC/TN ratios and low short-chain n-alkane flux indicated that terrestrial plants were the dominant contributors of the sequestrated OC. The major shift towards decreased OC burial occurred around 1972 CE and climate warming was implicated as a potential driver because it not only suppressed clastic material export and the associated carry of organic matter (OM) to lake sediments via amplifying catchment tree productivity but also accelerated OM degradation in lake water column. In Lake Wodi Co, phytoplankton were inferred to contribute the most to the sediment OC given the low TOC/TN ratio and high short-chain n-alkane flux. The OC burial rate significantly increased since ca. 1978 CE, probably initiated by a strengthened input of clastic materials and a parallel promotion of phytoplankton productivity linking to climate warming and intensified atmospheric N deposition, respectively. The above results demonstrated distinctly different OC burial patterns between the two alpine lakes in the context of climate warming and intensified atmospheric N deposition, probably forced by catchment dependent processes, which provided important implications for anticipating OC burial of alpine lakes under further climate and atmospheric N deposition scenarios.

82. 题目: Comparison of automated chemical-guided segmentation and human annotation of soil organic matter in X-ray microcomputed tomography imaging in contrasted soil types
文章编号: N26040501
期刊: Geoderma
作者: Jia Hao He, Andrew J Margenot, Yuhei Nakayama, Viktor Nikitin, Y.Zou Finfrock, Odeta Qafoku, Tamas Varga, Neslihan Taş, Elizabeth C Gillispie, Amisha Poret Peterson, Andrew J McElrone, Devin A Rippner
更新时间: 2026-04-05
摘要: Soil organic matter (OM) formation and persistence is strongly influenced by the spatial distribution of organic substrates and microscale soil heterogeneity by dictating OM accessibility to microorganisms. However, traditional size and/or density fractionation techniques disrupt aggregate architecture, eliminating spatial information needed to fully understand intra-aggregate OM distribution. To quantify three-dimensional OM spatial distribution and automate segmentation in X-ray microcomputed tomography (μCT) imaging without human annotation bias, we developed an iodine gas vapor (I2) based staining workflow that eliminates labor-intensive manual annotation while maintaining segmentation accuracy, using aggregates from four taxonomically diverse soils (Xerofluvent, Haploxeroll Sphagnofibrist, Palehumult) with an 8-fold range of soil organic carbon. Human annotation of 10 μCT slices by the experienced and inexperienced annotators resulted in variations up to 3% in the Dice similarity coefficient (DSC), reflecting a degree of inherent subjectivity of manual labeling. Such inconsistencies are expected to compound as the number of manually annotated slices increases. Dual-energy μCT imaging at 33.1 keV (below the iodine (I) K-edge) and 33.2 keV (above the I K-edge) was used to resolve aggregate microstructure following I2 staining. The automated image subtraction pipeline identified OM regions by the I K-edge induced brightness increases, achieving DSC values of 0.58–0.83 relative to an experienced annotator. Sensitivity analyses revealed that the reconstruction alpha value—optimized via the open-source tool TomocuPy—and the 3D registration slice count were the primary determinants of accuracy, providing a novel benchmark for dual-energy soil imaging. The pipeline without GPU acceleration was 9.6- to 43.2-fold faster than manual annotation. Using GPU-accelerated image post-processing and affine transformation matrices, the pipeline successfully segmented OM elements for large-scale datasets (3232 × 3232 pixel, 2048 slices) within ∼ 5200 s from raw file acquisition to segmented output. The high-throughput approach enables the quantification of OM spatial distribution across diverse and heterogeneous soils.

83. 题目: Rhizosphere microorganism is crucial to the DOM transformation and microbiome stability in the constructed wetlands
文章编号: N26040414
期刊: Chemical Engineering Journal
作者: Congyu Li, Xizhuo Wang, Patrick Lee, Siqing Xia, Liang Duan
更新时间: 2026-04-04
摘要: Constructed wetlands (CWs) play key roles in the water purification and host a range of processes that degrade and modify dissolved organic matter (DOM). Microbes in sediment and rhizosphere environments strongly influence DOM's chemodiversity. To unravel the biotic mechanisms that control the structure and patterns of DOM and microbial communities in CWs, we combined high throughput sequencing and 3DEEM. DOM components extracted by parallel factor analysis were mainly tyrosine-like, protein-like and tryptophan-like substance. Components and 4 optical indices showed season variation in the study periods. Sediment (SE) and rhizosphere (PR) microbial communities have some differences in dominant phyla and relatively larger proportions of generalist (5.32% and 2.89%) and specialist (1.57% and 1.23%) were estimated in PR systems than SE systems. Deterministic processes, especially homogeneous selection events (38.33%) were identified as the dominant microbial community assembly mechanisms in SE systems while stochastic process (58.33%) happens more often in PR system. The network pattern showed consistent results that extreme periods' network with lower stability will appear more dense modules than normal periods. Meanwhile, PR microbes could enhance the stability of SE community and benefit CW performance. DOM components had strong correlations with genera, which were also identified as biomarkers to classified SE and PR via random forest. PR's members have limited related to less DOM components in comparison with SE because of the narrow ecological niche and both two systems show function dependency. Finally, we figured out two pathways to decipher the interaction between DOM and CWs' microorganism, i.e., sediment microbes → DOM and sediment microbes → rhizosphere microbes → DOM. This study provides a new perspective for the construction and management of constructed wetlands.

84. 题目: Fates of polar organic contaminants in oxic sand columns: Impacts of sand type, hydraulic retention time and biodegradable organic carbon availability
文章编号: N26040413
期刊: Chemical Engineering Journal
作者: Pia Schumann, Pascal Hasselder, Aki Sebastian Ruhl
更新时间: 2026-04-04
摘要: Biotransformation in sand filters and natural subsurface barriers is a key process for eliminating organic micropollutants from drinking water. However, underlying mechanisms are complex and knowledge on influencing parameters is fragmentary. There is still a knowledge gap regarding contaminants of emerging concern, such as persistent and mobile substances, and their fate in those processes. This study investigated sorption and biotransformation of 18 polar and potentially persistent contaminants in oxic sand columns, evaluating the effect of biodegradable dissolved organic carbon (BDOC, drinking water vs. surface water), hydraulic retention time (9 h vs. 25 h) and sand type (microbial community, technical sand vs. sand from a groundwater recharge site). Substance and operation specific extent of biotransformation was observed. Overall, nine substances were biodegraded, while nine indicated persistence. Negligible sorption was observed, only the cationic 1,3-di-o-tolylguanidine was retarded by four bed volumes. The highest impact on biotransformation was observed for the parameter BDOC, followed by hydraulic retention time and finally sand type. The strongest effect was observed for 2-methyl-2-propene-1-sulfonic acid (MPSA), which was readily biodegradable in surface water and persistent under BDOC limiting conditions. Previous classifications as persistent, e.g. of 2-acrylamido-2-methylpropane sulfonate and adamantan-1-amine, were confirmed. Three substances previously categorized as persistent (acesulfame, MPSA and 4-hydroxy-1-(2-hydroxyethyl)-2,2,6,6-tetramethylpiperidine) showed biotransformation. These results emphasize the complexity of persistence assessments and the potential for some polar contaminants to be eliminated in treatment processes relying on biotransformation in the subsurface or sand filters under oxic conditions.

85. 题目: Uranium Adsorption by Extracellular Polymeric Substances from Desulfovibrio vulgaris UR1: Extraction Optimization and Binding Mechanisms
文章编号: N26040412
期刊: Journal of Hazardous Materials
作者: Juncheng Han, Jing Zou, Guangming Xu, Xinyao Liu, Likun Jiang, Haotian Yang, Guangsheng Zhu, Jiaxin Bai, Yanqing Guo, Peng Wang, Ling Luan, Junfeng Dou
更新时间: 2026-04-04
摘要: Extracellular polymeric substances (EPSs) play a crucial role in the microbial remediation of groundwater contaminated with radioactive uranium. In this study, EPSs were extracted from Desulfovibrio vulgaris UR1, a highly efficient uranium-reducing bacterium isolated from a uranium mining area, using six different treatment methods: heating, ultrasonication, centrifugation, pH adjustment, the addition of EDTA-2Na, and the use of a cation exchange resin. The physicochemical properties of the extracted EPSs were characterized through adsorption experiments and spectroscopic analyses. Compared with the other methods, heating at 318K resulted in the highest EPS extraction amount of 63.36mg·g–1 dry cell, while the cell viability was maintained above 80%. The extraction method significantly influenced the contents of protein and polysaccharide in the EPSs. EPSs obtained by heating at 318K exhibited a uranium adsorption capacity of up to 454.85mg·g–1, with carboxyl and hydroxyl groups in proteins identified as the primary functional groups responsible for adsorption. This work investigated the extraction methods and uranium adsorption performance of EPSs from Desulfovibrio vulgaris UR1, contributing to a better understanding of the adsorption mechanisms and resistance strategies of microorganisms in anaerobic groundwater environments contaminated with uranium.

86. 题目: Polylactic acid-based slow-release carbon source composite kaolin with modified biochar: Synergistic co-removal of nitrate, Cd(II), and diclofenac through manganese redox-coupled denitrification
文章编号: N26040411
期刊: Journal of Hazardous Materials
作者: Wenjing Cheng, Jingting Feng, Yue Wang, Junfeng Su, Yihan Bai, Yan Liu, Kun Pu, Xuan Li
更新时间: 2026-04-04
摘要: The problem of mixed pollution resulting from nitrate (NO3--N), cadmium(II), and diclofenac (DCF) due to incorrect discharge of industrial and agricultural wastewater has garnered significant attention. This study utilized polylactic acid (PLA) as a controlled-release carbon source, combined with kaolin and modified biochar, with the Pseudomonas sp. XFQ, to develop the manganese redox reactor G1, thereby improving denitrification efficiency and electron transfer capacity. This reactor was designed to synergistically remove NO3--N, Cd(II), and DCF. PLA in the composite carriers served as a stable sustained-release carbon source, continuously supplying bioavailable organic carbon to fuel microbial metabolism. When influent NO3--N concentration was 16.5 mg L−1, pH was 6.8, HRT was 8.0 h, bioreactor G1 demonstrated removal efficiencies of 99.8% for NO3--N, 91.0% for Cd(II), and 96.5% for DCF. Analysis demonstrated that manganese (Mn) modification improved the redox activity of biochar (BC), subsequently enhanced bacterial denitrification ability and resistance to Cd(II) and DCF. Additionally, microbial metabolism functions as a crucial mechanism for the removal of pollutants in fixed biofilm reactors (FBRs). The microbial community, primarily composed of Pseudomonadota, actively modulated its structure and gene expression associated with microbial metabolism to respond to the combined stress of Cd(II) and DCF. This research is of considerable importance for the treatment of mixed-pollutant wastewater.

87. 题目: Plant rhizosphere enhances biochar's immobilization of cadmium: Divergent effects in flooded and unsaturated cultivation soils
文章编号: N26040410
期刊: Journal of Hazardous Materials
作者: Yanying He, Peng Hu, Honglin Tao, Yunsi Xie, Wei Xiao, Xin Tang, Yingzhen Huang, Baobin Mi, Fangfang Wu
更新时间: 2026-04-04
摘要: Biochar demonstrates great potential for cadmium (Cd) immobilization in contaminated soils, yet the mechanisms governing its efficacy under dynamic water regimes and rhizosphere interactions remain insufficiently understood. A pot experiment was conducted using Cd-contaminated soil amended with lignin biochar (LBC) under two representative agricultural regimes: continuous flooding cultivation soil (TFS) and unsaturated cultivation soil (TDS). Results indicated that TFS promotes the formation of carbonate-bound cadmium (CA-Cd), while TDS, by enhancing the humification of soil organic matter (SOM), is more conducive to the formation of stable organic matter-bound cadmium (OX-Cd), exhibiting a better cadmium immobilization effect than TFS. Biochar enhanced cadmium immobilization by increasing soil pH, SOM, and cation exchange capacity (CEC), with its effect being most significant in TFS treatment. Multiple optical analyses and correlation analyses show that the composition and distribution of soil dissolved organic matter (DOM) are the core link connecting biochar, rhizosphere effects, water regulation, and cadmium speciation transformation. Both LBC treatment and TDS-induced rhizosphere activity promote DOM transformation towards high aromaticity, high negative charge, and high humification, thereby facilitating cadmium immobilization; additionally, these processes also affect fungal community structure, and the enrichment of key fungal communities participates in the stabilization of soil cadmium indirectly or directly through decomposition and transformation of organic matter and promotion of humus formation. These findings provide a mechanistic basis for leveraging plant-biochar synergies to tailor remediation strategies for specific water regimes in Cd-contaminated agroecosystems.

88. 题目: Understanding how fire impacts soil carbon and nutrient cycling: Towards standardized reporting of fire metrics for the integrated plant-soil system
文章编号: N26040409
期刊: Earth-Science Reviews
作者: Julia Gaudinski, Kate Wilkin, Jasquelin Peña, Mary Ellen Miller, Margaret S Torn
更新时间: 2026-04-04
摘要: Fire events impact soil carbon (C) and nutrient stocks immediately due to combustion of biomass and organic matter and set up additional post-fire changes to ecosystem inputs and losses. The literature on this topic is expanding rapidly as large and intense wildfires are increasingly affecting communities globally. However, many of these studies do not describe initial post-fire soil conditions adequately or consistently, nor do they link the impacts of fire on C and nutrient cycling to key soil properties and soil inputs, stocks and fluxes. Here we conduct a systematic analysis of 56 review-papers published in 2010 or later that address fire impacts to C and nutrient cycling and integrate relevant research from the fire ecology and soil carbon cycling literature. We begin with a conceptual framework that ties belowground changes to the soil system with aboveground changes.

89. 题目: Impacts of carbamazepine on simultaneous nitrogen and phosphorus removal and microbes in bioretention systems: a pivotal role of biochar and magnetite amendments
文章编号: N26040408
期刊: Journal of Environmental Chemical Engineering
作者: Xinyi Zou, Xue Wang, Kexin Ma, Jiaxin Liu, Wenwen Zhao, Ying Wang, Yan Xu
更新时间: 2026-04-04
摘要: To better understand the exposure response and mitigation mechanisms of carbamazepine (CBZ), a widely used psychotropic medication, in ecological water treatment systems, we established four bioretention systems (BRSs) (conventional system (C-BRS), biochar amended system (B-BRS), magnetite amended system (M-BRS), biochar/magnetite amended system (B/M-BRS)) and comprehensively investigated their performance under CBZ exposure (500μg/L) against a conventional control system (CK-BRS) over 150 days. The impacts and mechanisms were explored from the perspectives of nitrogen and phosphorous removal efficiencies, microbial community structures, as well as key functional genes and enzyme activities. Results indicated that total nitrogen (TN) and total phosphorus (TP) removal efficiencies gradually declined from 92.04% and 88.82% to 42.15% and 56.08% in C-BRS after CBZ exposure. However, the amendment of biochar and magnetite (B/M-BRS) favored higher TN (95.12%) and TP (95.20%) removals throughout the exposure. High-throughput sequencing results revealed that the functions of polyphosphate-accumulating organisms (PAOs) and denitrifying bacteria (DNB) were inhibited under CBZ exposure, which were in line with the reduced denitrifying functional gene nirK abundances (<106 copies/g) and nitrate reductase (NIR) activity. Fortunately, biochar and magnetite significantly increased the relative abundances of DNB (19.75–38.55%), and maintained high denitrification gene copy numbers (nirK, nirS, nosZ >10⁷ copies/g) sufficiently for denitrification. Meanwhile, BRSs containing magnetite exhibited elevated NIR activities, while biochar alleviated oxidative stress in plants caused by CBZ. Notably, CBZ exposure elevated antibiotic resistant genes (ARGs) dissemination risk (intI-1 rose from >10¹ to >10³ copies/g). These findings reveal ecological threats posed by CBZ to aquatic environments and promising mitigation strategies.

90. 题目: Continental records of the early Cretaceous OAE1a and mechanisms of carbon cycle perturbation driven by climate-weathering coupling in the Yin'e Basin
文章编号: N26040407
期刊: Palaeogeography, Palaeoclimatology, Palaeoecology
作者: Qianghao Liu, Rong Liu, Youyou Huang, Tianxin He
更新时间: 2026-04-04
摘要: This study investigates Lower Cretaceous Bayingebi Formation sediments in the Yin'e Basin, integrating petrological, mineralogical, organic/elemental geochemical, and biomarker analyses. During the OAE1a event (∼120 Ma), the regional climate shifted from warm-semiarid to warm-humid, which intensified terrestrial chemical weathering; fluvial erosion subsequently transported large amounts of nutrients into the lake, thereby enhancing lacustrine primary productivity. Increased terrestrial detrital input elevated lake salinity, stabilizing salinity stratification, while stagnant anoxic bottom waters facilitated organic carbon enrichment and preservation. Mechanistically, weathering intensity, biological pump efficiency, and salinity stratification jointly disrupted the lacustrine carbon cycle via a positive feedback loop: climate change → intensified chemical weathering → enhanced nutrient input/productivity → strengthened stratification/anoxia → promoted organic carbon sequestration. This study fills a gap in northern China's continental OAE1a response records, provides key geochemical constraints for Early Cretaceous global carbon cycle dynamics and lacustrine paleoenvironmental evolution, and integrates atmospheric-terrestrial-aquatic perspectives—deepening understanding of paleoclimate‑carbon cycle regulation across spheres in land-lake systems.

91. 题目: Pilot-scale phosphate recovery with biosolids biochar: Performance, phosphorus bioavailability and biochar quality assessment
文章编号: N26040406
期刊: Separation and Purification Technology
作者: Sabolc Pap, Thomas Thompson, Peter Juel Gronbjerg, Tamsyn Kennedy, Ilgaz Cakin, Mark A Taggart
更新时间: 2026-04-04
摘要: Phosphorus (P) recovery from wastewater using biochar made from biosolids represents a promising solution to improve P circularity not only in the water sector but more broadly. This study provides a ‘proof the concept’ for a pilot scale P recovery system based on P adsorption onto biosolids biochar (SSB-O). The generated P-loaded biochar is then assessed in terms of P bioavailability and for its quality (given its potential to be applied to soil). The pilot trial explored the SSB-O's capacity to remove phosphate (PO43−-P) from final wastewater effluent at environmentally relevant levels, whilst meeting stringent discharge limits for P as per the revised EU Urban Wastewater Treatment Directive (<0.7 mg P/L). The pilot unit was packed with ~17 kg of SSB-O and tested with an empty bed contact time (EBCT) of 15 mins, equivalent to a 150 L/h flowrate through the reactor. PO43−-P removal efficiency reached a maximum of 92%, while the process maintained <0.7 mg P/L discharge during the operational period of 383 h (for a treated wastewater volume of 57.6 m3; equivalent to 859 Bed Volumes (BV)). The spent SSB-O contained ∼8% P2O5 and was rich in macro elements (K, Ca, etc.). Trace concentrations of heavy metals (including Pb, Cd, Ni, Cr, As, Zn), PAHs, and PFAS/PFOS were also detected, but these were well below threshold limits set by the current European Biochar Certificate (EBC) and World Biochar Certificate (WBC) biochar quality guidelines. Only Cu exceeded the limits defined by the World Biochar Certificate. P bioavailability and heavy metal mobility were assessed using four different chemical extractants. Although only a limited fraction of P was readily available, further studies are required to substantiate the biochar's agronomic value and confirm its long-term phosphorus release characteristics. Minimal risk of heavy metal leaching was also observed. While further development is required, this study demonstrates the potential of biosolid-derived biochar as an adsorbent for phosphate removal from wastewater, as well as the possibility of reusing the P-enriched biochar across various primary and secondary sectors.

92. 题目: Mechanistic insights into molecular weight-driven and hydrophobicity-mediated effects on floc growth properties during two-stage ballasted flocculation for organics removal
文章编号: N26040405
期刊: Separation and Purification Technology
作者: Weipeng He, Zhen Yang, Ken Fang, Jiacheng Luo, Jinhong Zhang
更新时间: 2026-04-04
摘要: Conventional ballasted flocculation often faces challenges in achieving efficient and stable removal of natural organic matter (NOM) due to variable molecular weight (MW) characteristics and suboptimal chemical utilization. This study systematically investigated two staged injection strategies to overcome these limitations: (i) proportional two-stage injection of anionic polyacrylamide (PAM) with single-stage microsand addition; and (ii) simultaneous proportional two-stage injection of both PAM and microsand. Lab-scale flocculation tests were conducted using synthetic waters containing either molecular weight-fractionated humic acid (HA), or model NOM components with controlled hydrophobicity including HA, bovine serum albumin (BSA) and sodium alginate (SA). The results showed that higher-MW HA (>30 kDa) promoted the formation of larger, denser flocs and achieved superior removal of UV254 and DOC. Compared to the conventional single-stage operational mode, the two-stage injection of PAM alone significantly improved floc size uniformity across different water matrices and enhanced turbidity removal through optimized polymer bridging, while staged injection of PAM and microsand provided more controlled floc growth and minimized free microsand interference. Regarding organic hydrophobicity, the hydrophilic SA consistently modified floc development and settling, but the hydrophobic BSA inhibited aggregation, with HA and SA co-existence demonstrating synergistic benefits for floc growth. Mechanistic analysis via zeta potential measurements indicated that the overall floc formation process was predominantly governed by charge neutralization following alum coagulation and subsequent adsorption-bridging dominated by PAM. These findings suggest that staged chemical injection optimizes floc properties and removal performance, offering a viable strategy for enhanced NOM removal in ballasted flocculation.

93. 题目: How to achieve artificial aging approaching natural aging: Long-term remediation effects of biochar on cadmium contamination in soils
文章编号: N26040404
期刊: Geoderma
作者: Zhuowen Meng, Xin Liu, Shuang Huang, Weiyong Zhan
更新时间: 2026-04-04
摘要: Biochar effectively increases the pH of soils with sub-neutral pH values and immobilizes cadmium (Cd) in agricultural soils. The long-term remediation efficacy of biochar is a critical parameter for determining whether soil application is economically feasible. Various artificial accelerated aging methods have been developed; however, further research is required to better understand the utilization of artificially accelerated aging methods to approximate natural aging. This study innovatively established a quantitative simulation model for artificial aging that approximated natural aging across China’s six major regions on the basis of climate characteristics. The latest TabPFN model achieved superior fitting performance for both artificial and natural aging scenarios in terms of the impact of biochar on soil active Cd and pH. Significant differences were identified between the outcomes of artificial and natural aging. With respect to changes in the Cd immobilization rate of biochar, artificial aging exhibited a pattern of initial significant increase followed by a rapid stabilization (measured in days), whereas natural aging exhibited a continuous decline from high values followed by stabilization pattern (measured in years). In this study, under a precise simulation of Cd immobilization rates and pH changes following biochar application (1%, 2%, and 3% application ratios), the accelerated aging combinations reduced the natural aging scale (10 years) by 77.1%–94.6% in Northeast, South, North, Central, East, and Southwest China.

94. 题目: Molecular composition of dissolved organic matter determines lower-than-expected CH4 production in Mollisols under warming and atmospheric CO2 enrichment
文章编号: N26040403
期刊: Geoderma
作者: Jian Liu, Meng Zhou, Jian Jin, Lifeng Zhou, Run Dang, Eric Lichtfouse, Chuancheng Fu, Yang Tan, Jiafeng Yu, Peng Zhang, Han Lyu, Zhangliu Du, Leilei Xiao
更新时间: 2026-04-04
摘要: CH4 emissions from agricultural activities in response to anticipated climate changes, such as elevated temperature (warming) and elevated CO2 levels (eCO2), remain highly uncertain. In this study, warming, eCO2, and their combined effects were simulated using open-top chambers to elucidate the underlying mechanisms regulating CH4 emission potential from paddy soils. We found that single or combined warming and eCO2 uniformly reduced CH4 emission potential, decreased by 17.0 to 32.7%. A suite of complementary analyses, including carbon isotopic tracing, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and microbial metagenomic and metabolomic profiling, were conducted to uncover the underlying mechanisms. We discovered only a marginal change of microbial community, metabolism and dead residuals (microbial necromass carbon). In comparison, CH4 production was primarily mediated by shift in dissolved organic matter (DOM) molecular composition. An increase of lignin-like compounds combined with a decrease of carbohydrate explained the changes in CH4 production. Variance partition analysis and structural equation model also evidenced the importance of DOM molecular composition rather than microbial traits on regulating CH4 production. This study highlights an important role of DOM chemical stability in regulating CH4 emissions in a changing world.

95. 题目: Natural forest conversion to exotic pine plantations induces soil mineralogical and physicochemical changes – implications for soil organic carbon stabilization
文章编号: N26040402
期刊: Catena
作者: P Castillo, M F Albornoz, O Crovo, A Atenas, C I Czimczik, R Southard, F Aburto
更新时间: 2026-04-04
摘要: Extensive areas of native forests worldwide have been converted into exotic tree plantations, generating environmental impacts, including loss of biodiversity and alteration of critical hydrological and biogeochemical functions. Yet, the effect of this land-use change (LUC) on soil properties, especially mineralogy and carbon stabilization potential, has received less attention. This research assesses the impacts of converting former native temperate deciduous forests (Nothofagus) to evergreen conifer (pine) plantations on soils using paired plots. We compared soils to a depth of 2.4 m at five sites in south-central Chile under similar climates but contrasting soil types and parent materials, ranging from residual soils of crystalline rocks (schist [SCH-Ultisol] and granite [GR-Alfisol]) to pyroclastic deposits of different ages (recent ash [RA-Entisol], young ash [YA-Andisol], and old ash [OA-Alfisol]). Compared to native forests, plantation soils were more acidic, stored less organic carbon (SOC), and had lower exchangeable cations and higher exchangeable Al3+. Developed soils from pyroclastic deposits (OA-Alfisol and YA-Andisol) showed small changes in pH and Fe-Al near-crystalline phases. Conversely, well-developed soils from crystalline parent materials (GR-Alfisol and SCH-Ultisol) and weakly developed volcanic soils (RA-Entisol) were less resilient to this LUC, displaying changes in most physical and chemical properties, including changes in the relative abundances of near-crystalline and amorphous phases. Acidification, SOC losses, soil desiccation, and Al translocation were identified among the main processes modified by pine plantations. We found that soils with more substantial shifts in crystalline minerals (GR-Alfisol and YA-Andisol) were also more depleted in SOC and Fe-Al organometallic and amorphous phases at deeper horizons. Our findings highlight the delicate, mineral-dependent processes that stabilize and protect organic matter over decadal timescales. The substantial impact of forest conversion on mineralogical and physicochemical properties at greater soil depths than previously reported underscores the need to consider deeper soil compartments when evaluating LUC effects.

96. 题目: In situ analysis of carbon isotopes in various materials by laser-ablation isotope ratio mass spectrometry (LA-IRMS)
文章编号: N26040401
期刊: Chemical Geology
作者: Pengcheng Sun, Bin Hu, Changfu Fan, Jianfei Gao, Yanhe Li, Han Zhang, Houmin Li
更新时间: 2026-04-04
摘要: Carbon isotopes are an important geochemical tracer for studies in earth and environmental sciences. In the past few decades, in situ carbon isotope analysis has been successfully achieved by the secondary ion mass spectrometry (SIMS) and, more recently, the laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICPMS). However, these methods suffer from matrix effects and the scarcity of matrix-matched standards for correction. In this study, laser ablation isotope ratio mass spectrometry (LA-IRMS), which combines an excimer laser and an IRMS, was proposed to perform in situ carbon isotopes analysis in carbonate, graphite, diamond and organic matter samples with δ13CVPDB values covering a wide range (from −44.60 ‰ to +2.67 ‰). With precision better than ±0.39 ‰ (1SD), the measured values are consistent with their recommended values within the analytical uncertainty at spot size of 80–100 μm. Moreover, data showed that the matrix effects among these materials can be ignored, with biases less than ±0.24 ‰ when cross-corrected. We further applied this method to various diamond samples and carbonate rocks from Bayan Obo Fe-Nb-REE deposit. This method shed new light on the application of in situ carbon isotopes analysis.

97. 题目: One-Step Pyrolysis Synthesis of a Novel Iron Tailing/Biochar/Tourmaline Ternary Composite for Enhanced Sequestration of Cadmium from Aqueous Solution and Contaminated Soil
文章编号: N26040320
期刊: Water, Air, & Soil Pollution
作者: Wei Feng, Jing Lei, Hongli Diao, Shibin Xia
更新时间: 2026-04-03
摘要: The valorization of industrial solid waste into functional materials for environmental remediation represents a critical pathway towards a circular economy. However, developing a single, low-cost material that can effectively remediate heavy metal contaminants across both aquatic and terrestrial ecosystems remains a significant challenge. Here, we report the one-step pyrolysis (at 550 °C) synthesis of a novel ternary composite from iron mine tailings (IT), biochar (BC), and tourmaline (BT) at an optimized mass ratio of 1:4:1. The resulting IT-BC-BT composite exhibits a hierarchical porous structure with a specific surface area of 187.56 m2/g (a 68.4-fold increase over raw tailings). In aqueous environments, it demonstrated exceptional performance, achieving a theoretical maximum Cd(II) adsorption capacity of 41.52 mg/g, predominantly governed by a chemisorption-driven pseudo-second-order kinetic mechanism. Furthermore, in a 90-day soil incubation experiment, the 4% (w/w) composite application effectively immobilized Cd by significantly elevating soil pH and organic matter, leading to a dramatic 88.91% reduction in its leaching potential and driving a 20.9% increase in the stable residual fraction of Cd. When applied to a 60-day plant-soil system, the composite worked synergistically with Chrysopogon zizanioides, remarkably increasing shoot and root biomass by 89.9% and 57.8%, respectively, while restricting root-to-shoot Cd translocation (translocation factor < 1). Ultimately, these quantitative findings demonstrate a powerful waste-valorization strategy, transforming a problematic industrial byproduct into a robust, multi-platform material for sustainable pollution control.

98. 题目: Degradation Kinetics for Organic Nitrogen in Bioelectrochemical Systems toward Ammonia Recovery
文章编号: N26040319
期刊: ACS ES&T Engineering
作者: McKenzie Burns, Ziyan Wu, Tia Mirsha, Andrew Beaudet, Katie Mangus, Mohan Qin
更新时间: 2026-04-03
摘要: Land application of dairy manure returns nitrogen (N) to the soil for crop production. However, direct land application of manure faces challenges such as nitrogen volatilization and imprecise manure nitrogen applications, which significantly contribute to losses to the environment while also reducing the nitrogen value of manure. Manure processing methods that can recover nitrogen, particularly organic nitrogen (orgN) in a mineralized form, in a concentrated product can increase the nutrient use efficiency, reducing the demand for manufactured nitrogen fertilizers. In this study, we investigate two operation configurations of bioelectrochemical systems (BES) for ammonia (NH₃) recovery from orgN in synthetic dairy manure. Glutamic acid, an amino acid found in high concentrations in dairy manure, was used as the N source in the synthetic feed, and the BES was operated in both microbial electrolysis cell (MEC, E_appl. = 0.8 V) and microbial fuel cell (MFC) operation modes. Samples from four time series experiments, two in each operation mode, were analyzed for chemical oxygen demand (COD), total nitrogen (TN), total ammoniacal nitrogen (TAN), and acetate concentrations. Raman spectroscopy was applied to track the orgN content in the time series samples throughout the experiments. Results indicated superior N removal from the anolyte in MEC mode, with an average TN removal above 95% and first-order degradation kinetics with rate coefficients between 0.05 and 0.06 h^–1. Kinetic analysis of the Raman data revealed that glutamic acid degradation to be complex and not singularly ordered in either operation mode, requiring further quantitative study. This work provides vital insight into the kinetics of degradation within BES toward a more complete understanding of anode-chamber processes. Such insight can be useful in guiding further research into BES as resource recovery mechanisms and supporting BES adaptation as manure treatment processes focused on the recovery of nutrient-rich, value-added fertilizer products.

99. 题目: Biochar‐Modulated Microbial Communities Improve Phosphorus Cycling and Rice P Uptake in Low‐P Paddy Soil
文章编号: N26040318
期刊: Land Degradation & Development
作者: Yixuan Chen, Yongjia Shi, Jun Meng, Jiayi Li, Siyu Wang, Zhonghua Wen, Haoyue Zheng, Ziyi Ge, Wanning Dai, Li Lin, Xu Su, Wenfu Chen
更新时间: 2026-04-03
摘要: Phosphorus (P) is a key macronutrient for plants. Nevertheless, its low efficiency and overuse in paddy soil were addressing important agricultural and environmental issues. Biochar has been generally accepted as an effective and environmentally friendly material for improving soil fertility, but its role in soil P cycling and related microbial processes has not been adequately understood. In this study, a field microcosm experiment was carried out to assess the impact of three biochar types (rice husk biochar, BC; low‐phosphorus biochar, LP; high‐phosphorus biochar, HP) at two rates (0.5% and 2%, w: w) on soil P fractions, arbuscular mycorrhizal (AM) fungal colonization, microbial community structure, and rice growth. Biochar addition significantly increased soil pH, total carbon content, and total nitrogen content, and also significantly affected soil P fractions by increasing P availability. HP addition significantly increased soil total P, available P, and phosphatase activity by 3%, 158%, and 76%, respectively. Compared with all other treatments, the 0.5% HP treatment significantly increased rice shoot dry weight by 11% and 40% P accumulation in shoot and 29% in root, together with a higher AM fungal colonization rate. In contrast, grain yield was not significantly different among treatments, indicating that biochar addition mainly improved soil fertility and nutrient uptake ability rather than grain yield under the experimental conditions. Metagenomic analysis further showed that HP addition increased microbial richness and diversity and changed microbial community structure by reducing the relative abundance of Acidobacteria and Chloroflexi, increasing genes involved in fructose metabolism, and increasing the abundance of AM fungi and beneficial bacteria. In general, these findings showed that biochar, especially 0.5% HP, improved soil P cycling and microbial functional potential, and thus improved paddy soil P cycling and rice P uptake. This study emphasizes the importance of targeted biochar application as a sustainable approach for optimizing P management in paddy soils.

100. 题目: Global hotspots of particulate organic carbon losses under climate change
文章编号: N26040317
期刊: Nature Communications
作者: Siyi Sun, M Francesca Cotrufo, R A Viscarra Rossel, Carsten W Mueller, Morimaru Kida, Ailsa G Hardie, Alec Mackay, Alexander H Krichels, Wulf Amelung, Amit Kumar, Azamat Suleymanov, Baoku Shi, Bernard Jackson Cosby, César Plaza, César Terrer, Chang Liang, Chang Liao, Christopher Just, Ding Guo, Emanuele Lugato, Enqing Hou, Fan Ding, Fazhu Zhao, Feng Tao, Fernando T Maestre, Franco Bilotto, Fuzhong Wu, Gisela V García, Gongwen Luo, Guangxuan Han, Guillermo A Studdert, Guillermo Hernandez-Ramirez, Guoxiang Niu, Gervasio Piñeiro, Gustavo Saiz, Haikuo Zhang, Hamada Abdelrahman, Haodi Xu, Inma Lebron, Irina Kurganova, Jennifer Blesh, Jeppe Å Kristensen, Ji Liu, Jiacong Zhou, Jianping Wu, Jitendra Ahirwal, Junji Cao, Jørgen E Olesen, Karin Kauer, Katerina Georgiou, Kees Jan van Groenigen
更新时间: 2026-04-03
摘要: Soil organic carbon (SOC) comprises particulate (POC) and mineral-associated organic carbon (MAOC), which differ in formation, stabilization, and loss mechanisms. While the current global distribution of POC and MAOC is characterized, their vulnerability under future climate scenarios remains unclear. Using 3284 topsoil (0-30 cm) observations from six continents, we identify high-latitude soils as global hotspots of SOC vulnerability under shared socioeconomic pathway scenarios (SSP126, SSP245, and SSP585). Under a high-emission scenario (SSP585), high-latitude soils are projected to lose substantial POC by 2100, accounting for about 81 ± 10% of total SOC losses. These declines are driven by the high proportion of SOC stored as POC (fPOC) and its high temperature sensitivity. We show that fPOC is a robust indicator of SOC vulnerability to climate change. Globally, the projected POC decline corresponds to a cumulative carbon dioxide (CO2) release of 81.34 Pg CO2-equivalent by 2100, highlighting the importance of preserving POC to mitigate climate feedbacks.