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1. 题目: Differential effects of Phragmites australis versus Spartina alterniflora biochar on salt marsh soil improvement and carbon stabilization
文章编号: N26031209
期刊: Frontiers in Environmental Science
作者: Xiaowen Lin, Ge Song, Xin Luo, Jiangping Lai, Weiting Zhang, Jin-e Liu, Jinlou Huang, Shanshan Xu, Khan Waqas, Sun Minnan, Jing Bi
更新时间: 2026-03-12
摘要: Biochar is an effective strategy for improving physicochemical properties of coastal salt marsh soil and enhancing carbon stabilization. In this study, Spartina alterniflora (S. alterniflora) and Phragmites australis (P. australis) were used as biochar materials. Four pyrolysis temperatures (350 °C, 450 °C, 550 °C, and 650 °C) and three addition amounts (1%, 2%, and 3%) were applied to explore the effects of the two biochars on the physicochemical properties and carbon components of salt marsh soil. The results showed that both S. alterniflora biochar (SBC) and P. australis biochar (PBC) significantly increased soil pH, cation exchange capacity, and nutrients (SBC: 5.3%–188.6%; PBC: 1.4%–200.9%). The addition of biochar at 3% significantly increased soil total nitrogen (TN), Nitrate nitrogen (NO3−), and available phosphorus (AP) contents, thereby effectively enhancing soil nutrient supply capacity. The addition of SBC and PBC altered the composition of soil organic carbon (SOC), significantly increasing the proportion of mineral-associated organic carbon and thereby promoting SOC stability, particularly under high addition amounts and pyrolysis temperatures. These findings suggest that both SBC and PBC hold promise for improving soil carbon stabilization in coastal salt marsh soils. This study provides a valuable approach for saline–alkali soil remediation in coastal wetlands and offers a potential pathway for the resource utilization of S. alterniflora and P. australis.

2. 题目: Fabrication of ZIF-8 in porous biochar by a novel Zn-activation combined in-situ growth strategy for enhanced Pb removal
文章编号: N26031208
期刊: Separation and Purification Technology
作者: Ying Jiang, Wanting Wang, Guichun Luo, Yungui Li, Yapeng Dong, Xiuyuan Zuo, Hai Liang
更新时间: 2026-03-12
摘要: ZIF-8-decorated biochar hold great potential for heavy metal contaminated wastewater remediation due to the superior adsorption performance of ZIF-8. However, the inevitable blockage of nature pore during preparation restricted the enhancement of adsorption performance and further practical applications. Herein, a novel Zn(NO₃)₂ activation-combined in-situ growth strategy was established for porous ZIF-8-decorated biochar (AI-BC@ZIF-8) preparation, this strategy enables the synergistic promotion of porous structure and distribution of ZIF-8 for adsorbent. The AI-BC@ZIF-8 exhibited an excellent adsorption capacity of 249.63 mg/g for Pb, achieving removal efficiency of 99.8% for conventional 50 mg/L Pb-containing wastewater. The adsorption process conforms to the pseudo-second-order kinetic model and the Langmuir isothermal model, indicating the monolayer chemical adsorption mechanism. The results of FTIR, BET and XPS analyses indicate that the adsorption mechanism of AI-BC@ZIF-8 is electrostatic interaction, N-coordination, precipitation, ion-exchange and pore-filling. Overall, this adsorbent demonstrates outstanding adsorption performance, showing its great potential in efficient and low-cost water purification. This work provides a viable strategy for the synthesis of highly porous and efficient ZIF-8-decorated biochar for heavy metal removal from wastewater.

3. 题目: Irreversible sequestration of monensin by functionalized Moroccan clay-alginate-CMC/biochar microcomposite beads: Physicochemical and computational insights
文章编号: N26031207
期刊: Separation and Purification Technology
作者: Jaber Raissouni, Khalid Draoui, Ahmed Ait Aghzzaf, Raquel Cela-Dablanca, Ana Barreiro, María J Fernández-Sanjurjo, Esperanza Álvarez-Rodríguez, Avelino Núñez-Delgado
更新时间: 2026-03-12
摘要: Monensin (MON), a highly toxic ionophore antibiotic widely used in veterinary medicine, is classified as a priority environmental pollutant due to its persistence in aquatic and terrestrial ecosystems. This study aimed to develop and assess hydrogel microspheres composed of alginate (AL), carboxymethyl cellulose (CMC), biochar (BC), and non-swelling red Moroccan clay (NSW) as effective adsorbents for MON removal. Several formulations NSW-AL, NSW-AL-BC, NSW-AL-CMC, AL, and AL-CMC were synthesized and characterized. X-ray diffraction was used to study their crystalline structures, while Fourier-transform infrared spectroscopy identified functional groups involved in adsorption. Scanning electron microscopy revealed morphological and textural features. Additionally, computational methods including Density Functional Theory, molecular electrostatic potential mapping, Mulliken charge analysis, Monte Carlo simulations, and Hirshfeld surface analysis were applied to understand the adsorption mechanism. Experimental results showed that AL, AL-CMC, NSW-AL-CMC beads, BC, and NSW exhibited adsorption capacities up to 800 μmol/kg (100%) for MON. Notably, NSW-AL-CMC achieved ≈100% adsorption efficiency with no desorption, indicating outstanding stability and binding affinity. These findings highlight the potential of NSW-AL-CMC hydrogel beads as an efficient, eco-friendly material for MON removal, offering a promising strategy for mitigating environmental contamination and protecting public health.

4. 题目: Environmental remediation of antibiotics and herbicides using artificial humic substances
文章编号: N26031206
期刊: Separation and Purification Technology
作者: Khatereh Pakzad, Markus Antonietti, Alexander Volikov
更新时间: 2026-03-12
摘要: The sustainable mitigation of antibiotic and herbicide residues requires materials that integrate effective contaminant sequestration with soil quality improvement. Here, we present a novel, scalable strategy for synthesizing artificial humic substances (AHS) from poplar bark via alkaline hydrothermal humification, which accelerates natural humification pathways and generates a supramolecular structure rich in carboxyl, phenolic, and quinone functional groups. The engineered AHS was assessed for selective removal of tetracycline (TC), sulfamethoxazole (SMX), and atrazine (ATZ). Under optimized neutral conditions (pH 7.0, ambient temperature), AHS achieved adsorption capacities of 65.8, 10.7, and 10.8 mg/g for TC, SMX, and ATZ, respectively, driven primarily by hydrogen bonding, π–π stacking, and electrostatic forces. Kinetic analysis followed a pseudo-second-order model, and equilibrium data were consistent with the Langmuir isotherm (R² ≥ 0.985), indicating monolayer adsorption on a mesoporous surface. Competitive adsorption experiments demonstrated strong selectivity toward TC (K_TC/SMX = 5.21; K_TC/ATZ = 2.56). Soil amendment with AHS significantly enhanced pollutant immobilization, achieving >95% removal of TC and SMX after four weeks of aging. Dynamic leaching experiments demonstrated that a layered AHS-soil configuration functions as a superior reactive barrier compared to homogeneous mixing. Collectively, these results demonstrate that poplar bark-derived AHS offers a robust, bifunctional platform for integrated water purification and soil remediation, providing a practical and environmentally sustainable approach to mitigate organic pollutants.

5. 题目: Microbially enhanced dissolution of calcite in sinking marine particles
文章编号: N26031205
期刊: Proceedings of the National Academy of Sciences of the United States of America
作者: Benedict Borer, Adam V Subhas, Matthew G Hayden, Ryan J Woosley, Andrew R Babbin
更新时间: 2026-03-12
摘要: Evidence for the shallow cycling of calcium carbonate in the global ocean is mounting, but the mechanisms driving the dissolution of thermodynamically stable polymorphs, like aragonite and calcite, in the surface ocean remain unconstrained. Here, we quantify how microbial metabolism creates acidic microenvironments in marine particles that enhance the local dissolution of calcite despite supersaturated conditions in bulk waters. A temporal decoupling of particle deoxygenation and acidification suggests that respiration-derived carbon dioxide is not the sole driver of the observed undersaturation. Rapid dissolution occurs in particles exhibiting bacterial growth, with rates exceeding abiotic dissolution at the same bulk saturation by more than an order of magnitude. We observe the highest particle-associated dissolution rates at intermediate settling velocities, indicating that a trade-off between elevated mass transfer due to settling and bacterial respiration governs the ensuing dissolution rates. Translation of our experiments to the water column suggests that microbially driven undersaturation in marine particles may dissolve sufficient calcite in the mesopelagic ocean to extend particle transit times by eliminating this vital ballast mineral, reducing the efficiency of organic carbon sequestration.

6. 题目: Straw Incorporation Strategies Regulate Detritusphere Organic Carbon and Nutrient Accumulation
文章编号: N26031204
期刊: European Journal of Soil Science
作者: Deqiang Zhao, Weibao Yu, Robert W Brown, Zixi Liu, Yiping Xu, Zhitong Wang, Zexue Li, Yi Xu, Pinshang Xu, Davey L Jones, Yuan Wen, Shunli Zhou
更新时间: 2026-03-12
摘要: Straw incorporation is a widely adopted agricultural practice, with the detritusphere formed through straw‐soil interactions serving as a critical hotspot for nutrient cycling and soil organic carbon (SOC) accumulation in farmland soils. However, the detritusphere has been largely overlooked, and its relationship to straw component release and responses to management practices remains poorly understood. This study investigated the mechanisms of straw component release, nutrient cycling, and SOC accumulation in the detritusphere under four straw management regimes: straw mulch (SM), surface incorporation (SI), deep‐ploughed straw incorporation (DP‐SI), and deep‐injection straw incorporation (DI‐SI). Incorporated straw sequentially provides carbon sources to the detritusphere in the order of cellulose, hemicellulose, and lignin. After one year, the detritusphere under DI‐SI and SM retained higher straw residues, at 15.7% and 18.0%, respectively, and exhibited higher soil nutrients and SOC content, with an average increase of 24.5% and 28.4% compared to the bulk soil. Subsoil straw incorporation (DP‐SI and DI‐SI) resulted in a 2‐ to 7‐fold increase in nutrient availability, microbial biomass carbon, and enzyme activities in the detritusphere than topsoil straw incorporation (SM and SI). In the detritusphere, the transition of carbon sources from easily decomposable to recalcitrant substrates led to a shift in SOC dynamics, with net accumulation shifting to net loss at a critical threshold of ~71% straw decomposition. In conclusion, the biochemical characteristics of the detritusphere are closely linked to the release and retention of straw components, which are strongly influenced by straw incorporation strategies. DI‐SI retained more straw residues in the detritusphere and demonstrated substantial potential for improving soil nutrient cycling, enzyme activity, and SOC accumulation.

7. 题目: Contrasting Effects of Long‐Term Fertilization on Pore Structure and POM in Upland and Paddy Soils Revealed by X‐Ray CT
文章编号: N26031203
期刊: European Journal of Soil Science
作者: Zichun Guo, Tianyu Ding, Jiaqi Li, Kailou Liu, Yan Wu, Shangshu Huang, Lei Gao, Xinhua Peng
更新时间: 2026-03-12
摘要: Soil pore structure plays a fundamental role in particulate organic matter (POM) dynamics by regulating water and air exchange within the soil matrix. However, the effects of long‐term fertilization on POM distribution, pore characteristics, and their interrelationships may differ between upland and paddy soils. In this study, we examined two long‐term fertilization field experiments conducted in contrasting agroecosystems in Jiangxi, China: a 38‐year upland field and a 43‐year paddy field. Four fertilization regimes were compared: no fertilizer (control), inorganic fertilizer (NPK), double‐rate inorganic fertilizer (2NPK), and inorganic fertilizer combined with pig manure (NPKM). X‐ray computed tomography (CT) was used to quantify soil pore structure and POM, and a random forest model was trained on a manually classified dataset of 1322 POM fragments to operationalize the decomposition degree, distinguishing fresh (e.g., exhibiting low blobness, plateness) from decomposed (e.g., exhibiting high sphericity, compactness) morphologies based on four morphological features. The NPKM treatment significantly increased fresh and decomposed POM volume density by 2.05% (7.51 mm 3 cm −3 ) and 47.7% (2.01 mm 3 cm −3 ) in upland soil, and 253% (15.2 mm 3 cm −3 ) and 103% (1.47 mm 3 cm −3 ) in paddy soil, respectively. NPKM also enhanced air permeability ( K a ), image‐based porosity, connected porosity, > 300 μm porosity, and surface area density in both soils. POM in upland soil is rapidly aerobically decomposed and physically fragmented within dynamic pore networks, while in paddy soil, it is preserved by anaerobic conditions that suppress microbial activity. Overall, our findings demonstrate that combined organic–inorganic fertilization promotes both POM accumulation and the development of pore structure in upland and paddy soils, with distinct mechanisms operating under different land‐use systems.

8. 题目: Soil Carbon Modeling at Crossroads: Building Reliable Methods for Policy and Practice
文章编号: N26031202
期刊: European Journal of Soil Science
作者: Laxman Bokati, Anil Somenahally, Saurav Kumar
更新时间: 2026-03-12
摘要: Soil carbon mapping (SCM) is rapidly becoming a cornerstone of soil science and environmental decision‐making, from precision agriculture to national carbon inventories. Yet SCM is at a crossroads: the methods that often promise high‐accuracy metrics can mask structural weaknesses that limit generalization and undermine policy relevance. Similar problems apply to larger Digital Soil Mapping (DSM). In this article, using soil organic carbon (SOC) as an illustrative example, we highlight three systematic sources of error that consistently inflate SCM performance: depth, bulk density, and spatial autocorrelation. Soil profile depth is often mishandled when profile increments are split between training and test sets, leading to inflated accuracy estimates. Bulk density (BD), essential for converting concentrations to stocks, is inconsistently applied and rarely accompanied by uncertainty estimates. SOC stocks at sampling locations are often derived using BD, and when BD is reintroduced as a predictor in machine learning models, it inflates reported accuracy and the model's predictive skill. Spatial autocorrelation further exaggerates accuracy when conventional random splits are used, while spatial blocking reveals much lower and more realistic predictive skill. Drawing on recent literature and our own analysis, we argue that SCM must adopt more rigorous practices, including profile‐level validation, spatially aware blocking, standardized reporting of assumptions, and alignment with policy‐relevant depth intervals. These steps will enhance comparability across studies and ensure that SCM outputs are credible for carbon accounting, climate mitigation, and land management purposes. The future of SCM and DSM depends on both new algorithms and methodological rigor and transparency.

9. 题目: Soil organic matter stabilization varies with nitrogen enrichment and hydrogeomorphic setting in a marsh-mangrove ecotone.
文章编号: N26031201
期刊: Science of the Total Environment
作者: Mercedes M Pinzon, Jocelyn Bravo, Samantha K Chapman, J Adam Langley, Lisa G Chambers
更新时间: 2026-03-12
摘要: As average global temperatures rise, coastal wetlands play a crucial role in carbon (C) sequestration and storage, primarily as soil organic matter (SOM). However, the poleward migration of mangroves into salt marsh habitats, along with nitrogen (N) pollution, may alter SOM formation and stability, and thus the capacity of coastal wetlands to preserve soil C long-term. Wetland SOM is composed of mineral-associated organic matter (MAOM), which is considered highly stable due to physicochemical protection, and particulate organic matter (POM), which has a more rapid turnover rate. This study evaluated the effects of mangrove presence, N enrichment, and hydrogeomorphic setting on SOM pools and biogeochemical soil properties in NE Florida, USA, to understand implications for long-term soil C and N preservation. A factorial field experiment (40 plots) tested interactions between hydrogeomorphic location (creekside vs. interior), vegetation (marsh vs. mangrove), and N treatment (fertilized vs. control), across two depths (0-15 and 15-30 cm) on MAOM and POM pools. Interior plots held 58% more MAOM-C and 61% more MAOM-N by mass than creekside plots, with control marshes MAOM-C and MAOM-N exceeding control mangroves. However, when normalized, MAOM accounted for 55.5% of total C and 73.8% of total N in creekside plots, compared to 44.3% and 61.2% in interior plots- suggesting greater C stabilization efficiency. N-fertilization effects varied by vegetation and location. In interior plots (0-15 cm), N-fertilization increased MAOM by 28-30% in mangroves, while decreasing MAOM by 20-21% in marshes. In creekside plots, N-fertilization had no main effect, though fertilized marshes held more MAOM than fertilized mangroves. Collectively, these findings underscore the need for site-specific assessments (vegetation, nutrient inputs, and hydrogeomorphic setting, etc.) of blue C potential as coastal vegetation and nutrient regimes continue to shift.

10. 题目: Acid rain triggers chromium re-mobilization in iron-biochar remediated industrial soils: Microscale insights from in situ imaging
文章编号: N26031105
期刊: Environmental Pollution
作者: Danxing Yang, Wen Fang, Haiyi Chen, Haitao Sun, Xing Liu, Jun Luo
更新时间: 2026-03-11
摘要: Iron-modified biochar (BCFe) shows promise for remediating Cr(VI)-contaminated industrial soils, but its long-term effectiveness under environmental stressors like acid rain require investigation. This study integrated column leaching, ex situ soil sampling, and in situ high-resolution (HR) imaging to assess acid rain effects (pH 4.0 vs. 5.6) on chromium (Cr) mobility, distribution, and speciation in BCFe-remediated Cr-contaminated industrial soils. BCFe exhibited high Cr(VI) adsorption capacity (184 mg g^-1) and significantly reduced Cr(VI) availability and leaching, promoting the transformation of Cr into more stable geochemical fractions. However, acid rain leaching increased Cr(VI) release compared to normal rainfall leaching. While ex situ analysis indicated Cr migration primarily affected the upper 0–8 cm, in situ HR imaging precisely resolved a distinct 3–5 cm transition zone exhibiting significant microscale heterogeneity. In situ evidence confirmed Cr(VI) reduction via simultaneous Cr(III) increase. Crucially, a strong negative correlation between labile Fe and Cr(VI) occurred only within BCFe treatments in this zone, verifying the key role of Fe(II) in Cr(VI) reduction. By integrating multi-scale (ex situ/in situ) techniques, this study revealed both the potential of BCFe for Cr remediation and the critical compromising effect of acid rain, highlighting the need to consider environmental factors for long-term efficacy.

11. 题目: Iron and nitrogen stress controls summertime biogeochemistry in the high‐latitude North Atlantic
文章编号: N26031104
期刊: Limnology and Oceanography
作者: Willem H van de Poll, Rebecca Zitoun, Loay J Jabre, Marieke M Bos, Anna C Koek, Wen‐Hsuan Liao, Sharyn Ossebaar, Patrick Laan, Erin M Bertrand, Rob Middag
更新时间: 2026-03-11
摘要: High‐latitude North Atlantic currents (60°–70°N) exhibit contrasting nutrient stoichiometries, but the spatial extent of post‐spring bloom iron (Fe) and nitrogen (N) stress on phytoplankton around Iceland remains poorly constrained. Here we pair in situ biogeochemical characteristics with 72 h Fe and N addition experiments in the East Greenland Current (EGC), Irminger Current (IC), Atlantic Current (AC), and East Icelandic Current (EIC) regions. Dissolved iron (dFe) was elevated in the EGC region and depleted in Atlantic surface waters. Unlike dFe, surface nitrate in the EGC region was depleted and elevated in Atlantic waters. Chlorophyll a (Chl a ) and particulate organic carbon standing stocks in the diatom and chlorophyte enriched EGC were ~ 40% lower than in the haptophyte dominated Atlantic waters. Changes in photophysiology during the incubation experiments revealed widespread Fe stress in the IC and in most of the AC stations. Notably, 80% of the experiments with nutrient stoichiometry suggesting Fe limitation (dFe < 0.2 nmol L −1 , N > 0.6 μ mol L −1 ) revealed Fe stress. In contrast, 30% of the experiments with nutrient stoichiometry suggesting N limitation (N < 0.6 μ mol L −1 , dFe > 0.2 nmol L −1 ) showed N stress, mainly in the EGC region. The EIC showed depleted concentrations of nitrate and dFe at the surface. Here, one incubation experiment revealed responses of combined N and Fe stress. The strong summertime density differences between the EGC and Atlantic water masses most likely limits the ability of advected dFe from Greenland and the Arctic to fertilize the Fe‐depleted Atlantic waters.

12. 题目: Evaluation of carbon and phosphorus metabolism in biochar-pyrite amended constructed wetland towards low C/N ratio wastewater: Performance, ecological stability and mechanisms revelation
文章编号: N26031103
期刊: Chemical Engineering Journal
作者: Xiuwen Qian, Juan Huang, Jin Xu, Jiawei Yao, Yiren Gao, Zhishui Liang, Chong Cao, Ming Tang
更新时间: 2026-03-11
摘要: In this study, conventional constructed wetland (CW) and CWs with individual biochar (BC) or biochar-pyrite (BCP) amendment were assessed. During 120 d-operation, average total phosphorus (TP) and chemical oxygen demand (COD) removal efficiency reached 96.2% and 84.3% in BCP amended group. Individual BC and combined BCP caused significant increase of TP removal by 15.7% (p < 0.001) and 16.1% (p < 0.001) than control, and 5.8% (p < 0.01) and 10.1% (p < 0.001) improvement in COD removal efficiency. Biochar amendment contributed to less fluxes of CO₂ and CH₄ than control, while coupled pyrite additionally decreased CO₂ and N₂O emission by 31.6% and 14.8% than individual BC. Biochar amendment had stimulation on plant photosynthesis and substrate dehydrogenase and phosphatase activity. Pyrite further raised electron transport system activity level by 54.7% (p < 0.001) compared with individual BC group. Combined BCP not only improved biofilm growth but also reduced bio-clogging risk, conducive for long-term operation. Bacteria participated in phosphorus metabolism and carbon fixation were enriched with BCP amendment, such as Acidobacteriota, Cyanobacteria, Saccharimonadales, Terrimonas, Sphingomonas, Bacillus, and Paracoccus, aligned with up-regulation of phosphorus cycling and carbon fixation genes. Moreover, abundance of key genes involved in Phosphotransferase system, Glycolysis, TCA cycle, and Pyruvate metabolism also increased with BCP amendment, improving microbial metabolic regulation, electron transferring and energy supply. Overall, this study provided new understandings for the improvement of carbon and phosphorus metabolism in BCP amended CWs.

13. 题目: Alterations in soil pH drive the impact of global change on glomalin-related soil protein: a global meta-analysis.
文章编号: N26031102
期刊: Journal of Environmental Management
作者: Jia Zeng, Xing Wang, Zhengchen Wang, Fang Chen, Jingbo Fang, Hongxia Wang, Chengjie Ren, Gaihe Yang, Zekun Zhong, Yiqi Luo, Thomas Ward Crowther, Xinhui Han
更新时间: 2026-03-11
摘要: Glomalin-related soil protein (GRSP), a key glycoprotein metabolite of arbuscular mycorrhizal fungi (AMF), plays a central role in soil carbon and nitrogen sequestration and aggregate stability. However, a systematic understanding of its response patterns and driving mechanisms under diverse global change factors (GCFs) remains limited. This study conducted a global meta-analysis to assess the effects of 14 GCFs (including land-use conversion, fertilization, and climate change) on the two GRSP fractions: easily extractable GRSP (EE-GRSP) and total GRSP (T-GRSP). The results demonstrated that T-GRSP exhibited more pronounced responses to GCFs than EE-GRSP, making it a superior indicator for characterizing long-term changes. Specifically, fertilization (nitrogen +28%; phosphorus +12%; nitrogen and phosphorus +44%; nitrogen, phosphorus and potassium +33%) and elevated CO2 (eCO2 +7%) significantly promoted T-GRSP accumulation (all relative to control, p < 0.05). In contrast, land-use conversions such as forest to bare land (-91%), farmland (-33%), shrubland (-36%), and grassland to farmland (-43%) significantly reduced T-GRSP. Warming, fire, and forest-to-grassland conversion showed no significant effects. Soil pH change was identified as the pivotal hub regulating GRSP responses to GCFs, governing GRSP accumulation dynamics by influencing its mineral adsorption and microbial decomposition. Furthermore, changes in T-GRSP were tightly coupled with soil organic carbon (SOC) and total nitrogen (TN), directly contributing to the stable C and N pool and indirectly enhancing physical protection through promoting aggregate formation. Notably, under climate change, the relationship between SOC, TN and T-GRSP showed decoupling. Concurrently, a significant negative correlation emerged between the proportion of T-GRSP in SOC, TN and their actual contents, revealing an adaptive strategy in which T-GRSP serves as a stable component for core protection. This study systematically elucidates the response patterns and mechanisms of GRSP to global change, highlighting its dual role in maintaining the stability of soil carbon and nitrogen pools.

14. 题目: Construction of SnO2/Bi2O2CO3 Z-type heterojunction for photocatalytic degradation of humic acid under sunlight.
文章编号: N26031101
期刊: Environmental Research
作者: Muxi Zhang, Chenchen Liao, Bin Dong, Wenjie Lin, Yu Chen, Penghui Yao, Xiaojie Sun, Hongxia Zhang
更新时间: 2026-03-11
摘要: The presence of humic acid (HA) significantly affects water purification and subsequent reuse processes. Its toxicity and potential to form carcinogenic trihalomethanes make the effective removal of HA particularly critical. In this study, SnO2/Bi2O2CO3 photocatalysts were synthesized via a one-step method without external carbonate addition and applied for the photocatalytic degradation of HA. Photocatalyst synthesis was verified by performing comprehensive characterization. In situ XPS and charge density differences indicate the transfer of e- from SnO2 to Bi2O2CO3, confirming the formation of Z-type heterojunction. This structure effectively promotes the separation of photogenerated e--h+ pairs, enhances the generation of ·O2- and ·OH, and thus improves photocatalytic performance. The removal rates of UV254, color number (CN) and TOC of SnO2/Bi2O2CO3 under sunlight were 87.53%, 92.16% and 78.50%, respectively. The seed germination experiment demonstrated that the seed germination index increased by 7.31% to reach 86.33% after photocatalytic degradation, indicating a decrease in toxicity of the HA. Photocatalysis mainly decomposed most CHO and CHON compounds through carboxylic acid reactions, oxygen addition reactions, and dealkylation reactions, and significantly reduced the number of molecules (from 7240 to 4018). Some fulvic acid and hyaluronic acid substances are degraded to form tyrosine substances and soluble microbial byproducts. This study uses CO2 in the air and does not require additional carbonates to synthesize Bi2O2CO3, providing a simple, green and feasible method for synthesizing SnO2/Bi2O2CO3 with excellent recyclability and reusability.

15. 题目: Deciphering the Role of Biochar on Ammonia Oxidation with Bicarbonate as an Electron Acceptor: Complete Nitrification of NH4+-N to NO3⁻-N Under Short-term Low-temperature Stress
文章编号: N26031016
期刊: Water, Air, & Soil Pollution
作者: Ruilin Wang, Jingang Huang, Jingya Liu, Huanxuan Li, Rongbing Zhou, Wei Han, Xiaobin Xu, Xiaoping Fu, Haibo Wang
更新时间: 2026-03-10
摘要: To overcome challenges of energy-intensive nitrification and nitrite-limited anammox, this study developed a biochar-assisted anaerobic NH4+-N oxidation process using bicarbonate (HCO3⁻) as a potential electron acceptor. While the biochar-free system primarily accumulated NO2⁻-N, bamboo biochar enabled the complete nitrification to NO3⁻-N, even under low-temperature stress (12–15 °C). The prolonged operation under lower temperatures (< 12 °C) diminished this enhancement and reduced nitrification efficiency, with persistent effects even after temperature recovery to 25 °C. Morphological and 16S rRNA sequencing results revealed distinct microbial communities in this bicarbonate-driven system compared to conventional anammox sludge. Biochar enhanced the resilience of the system against low-temperature stress by selectively enriching specific taxa, such as nitrifying bacterium Nitrobacter and the functionally associated nxrB gene, both of which were critical for complete nitrification. Machine learning with XGBoost modeling effectively predicted the nitrite accumulation ratio (NAR) and nitrogen removal efficiency (NRE), identifying operating temperature as the significant positive factor. The negative contribution of biochar dosage to NAR prediction further confirmed its role in prompting complete nitrification. Overall, this study presents a promising complete nitrification process to address low-temperature stress and electron acceptor limitations in NH4+-N removal.

16. 题目: Differential effects of Phragmites australis versus Spartina alterniflora biochar on salt marsh soil improvement and carbon stabilization
文章编号: N26031015
期刊: Frontiers in Environmental Science
作者: Lin Xiaowen, Song Ge, Luo Xin, Lai Jianping, Zhang Weiting, Liu Jin-e, Huang Jinlou, Xu Shanshan, Waqas Khan, Sun Minnan, Bi Jing
更新时间: 2026-03-10
摘要: Biochar is an effective strategy for improving physicochemical properties of coastal salt marsh soil and enhancing carbon stabilization. In this study, Spartina alterniflora ( S . alterniflora ) and Phragmites australis ( P . australis ) were used as biochar materials. Four pyrolysis temperatures (350 °C, 450 °C, 550 °C, and 650 °C) and three addition amounts (1%, 2%, and 3%) were applied to explore the effects of the two biochars on the physicochemical properties and carbon components of salt marsh soil. The results showed that both S. alterniflora biochar (SBC) and P . australis biochar (PBC) significantly increased soil pH, cation exchange capacity, and nutrients (SBC: 5.3%–188.6%; PBC: 1.4%–200.9%). The addition of biochar at 3% significantly increased soil total nitrogen (TN), Nitrate nitrogen (NO 3 − ), and available phosphorus (AP) contents, thereby effectively enhancing soil nutrient supply capacity. The addition of SBC and PBC altered the composition of soil organic carbon (SOC), significantly increasing the proportion of mineral-associated organic carbon and thereby promoting SOC stability, particularly under high addition amounts and pyrolysis temperatures. These findings suggest that both SBC and PBC hold promise for improving soil carbon stabilization in coastal salt marsh soils. This study provides a valuable approach for saline–alkali soil remediation in coastal wetlands and offers a potential pathway for the resource utilization of S. alterniflora and P . australis .

17. 题目: Molecular interaction of pristine and photoaged polylactic acid microplastics with extracellular polymeric substances from Microcystis aeruginosa
文章编号: N26031014
期刊: Environmental Research
作者: Hongwei Luo, Zhen Li, Shizhe Xu, Chaolin Tu, Chenyang Liu, Dongqin He, Jianqiang Sun, Xiangliang Pan
更新时间: 2026-03-10
摘要: Microplastics (MPs) existence in aquatic environments may cause changes in properties of water bodies and associated sediments. In freshwater systems, most of the photosynthetic products of phytoplankton are released in the form of extracellular polymeric substances (EPS). EPS often interact with some charged particles through specific functional groups in their macromolecules. An in-depth understanding of EPS-MPs interactions is essential to assess the environmental effects of MPs on freshwater and marine systems. In this study, the mechanism behind the interactions of pristine and photoaged polylactic acid microplastics (PLA-MPs) with EPS was systematically investigated at the molecular scale. Results show that the addition of EPS remarkably enhanced the fluorescence intensity of humic- and fulvic-like substances within pristine and aged PLA as revealed by fluorescence excitation-emission matrix. Fourier transform infrared spectroscopy, Raman spectra, and atomic force microscopy coupled with infrared spectroscopy (AFM-IR) further demonstrated that interactions between EPS and pristine PLA were mainly via hydrogen bonding-induced local chain rearrangement or breakage. Meanwhile, aging of PLA led to the stronger interaction with EPS. Compared with pristine PLA, aged PLA exhibited more pronounced surface alteration and molecular weight reduction after exposure to EPS under the applied experimental conditions, suggesting a greater susceptibility to hydrolytic transformation. Moreover, the aged PLA displayed pronounced cracks and grooves, especially after reaction with EPS. EPS addition also increased the negative surface charge of PLA, especially in aged PLA. This study highlights the complexity of PLA-EPS interaction mechanisms, and offers a possible view on predicting the environmental behavior of MPs and regulating their biodegradation process.

18. 题目: Molecular Composition of Soil-Derived Dissolved Organic Matter Regulates Photodegradation of 6PPD-Quinone
文章编号: N26031013
期刊: Journal of Environmental Chemical Engineering
作者: Jiale Liu, Linbin Zhu, Hua Yin, Yibo Yuan, Yuhao Cai, Shaoyu Tang, Junfeng Niu
更新时间: 2026-03-10
摘要: The tire rubber antioxidant transformation product N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) has emerged as widespread contaminant, raising serious ecological concerns. Soil-derived dissolved organic matter (SDOM) is a major source of photochemically produced reactive intermediates (PPRIs) that mediate pollutant transformation in terrestrial environments. This study investigated 6PPD-Q photodegradation with different SDOM. The results revealed that SDOM significantly accelerated the photodegradation of 6PPD-Q, with black soil-derived DOM (BS-DOM) indicating a 49.5% increase, significantly higher than the 13.7% and 23.5% enhancements observed with yellow soil-derived DOM (YS-DOM) and red soil-derived DOM (RS-DOM), respectively. Electron paramagnetic resonance (EPR) and quenching experiments indicated that hydroxyl radicals (•OH) served as the primary reactive species responsible for 6PPD-Q degradation. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and spectroscopy analyses revealed that abundant lignin-like components and moderate sulfur contents in BS-DOM facilitated efficient •OH generation, thereby exerting the most significant accelerating effect on 6PPD-Q photodegradation. High-resolution orbitrap mass spectrometry further identified 22 intermediates, with hydroxylation, C-N bond cleavage, and quinone decomposition as the main degradation pathways, leading to less toxic products than the parent compound. These results underscore the critical role of DOM composition in 6PPD-Q photodegradation and offer fresh perspectives on the environmental fate of 6PPD-Q in soil-associated system.

19. 题目: Electrical Stimulation-Induced π-π Stacking Drives Sludge Humification to Enhance Direct Interspecies Electron Transfer and Methanogenesis
文章编号: N26031012
期刊: Water Research
作者: Lujun Wang, Zhihao Jiang, Qilin Yu, Yaobin Zhang
更新时间: 2026-03-10
摘要: Electrical stimulation has been applied to enhance anaerobic digestion (AD), but its underlying mechanisms remain unclear. This study reveals that electrical stimulation accelerates sludge humification during AD by driving π-π stacking of humic precursors, thereby enhancing electroactivity and methanogenesis. Specifically, methanogenic potential and HA content increased by 42% and 75.1%, respectively, compared to the control (without electrical stimulation). X-ray photoelectron spectroscopy (XPS) revealed intensified π-π stacking interactions in the electrical stimulation group. Density Functional Theory (DFT) calculations confirmed that the electric field induces strong polarization of humic precursors (dipole moment ∼21 Debye). This polarization significantly strengthens intermolecular noncovalent interactions (lowering binding energy by 25.63 kcal/mol), serving as the thermodynamic driving force for π-π stacking. Consequently, this supramolecular assembly forms an extensive delocalized electron system, reducing charge transfer resistance by 56% and facilitating Direct Interspecies Electron Transfer (DIET). Furthermore, for the first time, ¹³C isotope tracing confirmed a strong correlation (R²>0.88) between conductivity and DIET contribution. The findings of this study provide a novel perspective for understanding and optimizing bio-electrochemical systems.

20. 题目: Differentiated Carbon Stabilization Pathways Reveal Cropland Promotes MAOC in the Yellow River Sediment‐Affected Area
文章编号: N26031011
期刊: Land Degradation & Development
作者: Ran Wang, Junhua Zhang, Shu Liu, Xixi Sun, Shengxin Wang, Hua Shang, Yaping Zheng, Rubing Li, Ziqi Jiang, Guodong Li
更新时间: 2026-03-10
摘要: Soil organic carbon (SOC) fractions play a crucial role in regulating biogeochemical cycles and carbon sequestration processes. However, in ecologically fragile regions such as the Yellow River sediment‐affected area, the long‐term dynamics and turnover mechanisms of particulate organic carbon (POC) and mineral‐associated organic carbon (MAOC) under different land‐use types remain unclear. Based on the 2013 and 2023 field samples, we examined planted forests, cropland, and orchard soils in the Yellow River sediment‐affected region to quantify 0–40 cm soil layer decadal changes in POC and MAOC, their sequestration pathways, and key drivers. All land‐use types exhibited significant carbon accumulation but followed differentiated sequestration pathways. In cropland, the increase in MAOC (2.17 g kg −1 ) in the 0–20 cm layer was 2.1 times that of POC (1.03 g kg −1 ), and the proportion of MAOC increased markedly from 43% to 51%. Orchard soils exhibited the highest MAOC accumulation in the surface layer (3.63 g kg −1 ) but showed a loss of POC in the 20–40 cm layer (−0.91 g kg −1 ). Planted forests showed steady increases in both POC and MAOC. Analysis of driving factors revealed that vegetation inputs and soil properties were key determinants of surface POC dynamics, while soil properties, particularly total nitrogen content and soil particle size, primarily controlled MAOC stabilization. This study demonstrates that modern agricultural practices characterized by straw incorporation effectively promote the conversion of labile POC into stable MAOC, providing key scientific evidence to optimize land management and enhance soil health and carbon sequestration efficiency in coarse‐textured soils.