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41. 题目: Unravelling the complex influence of dissolved organic matter on microbial diversity in a salinized lake
文章编号: N25010902
期刊: Environmental Research
作者: Weiying Feng, Xuezheng Yu, Jiayue Gao, Jin Hur, Fang Yang, Zhuangzhuang Feng, Haiqing Liao, José Manuel Gonçalves, Isabel Maria Duarte, Pingqing Fu
更新时间: 2025-01-09
摘要: Ecosystems in cold and arid regions, such as Dai Lake - a typical inland, salinized lake in the semi-arid region of northern China - face severe environmental challenges, including salinization and biodiversity loss. This study investigates the chemical composition of dissolved organic matter (DOM) and the structure of microbial communities in lake water and sediments, offering novel insights into the ecosystem's dynamics. In winter, DOM in the lake water is primarily derived from decaying plant and animal matter, while sediment DOM is predominantly associated with microbial activity. Statistical analyses revealed significant correlations between DOM components and key microbial species, including Firmicutes, Actinobacteria, α-Proteobacteria, and Acidobacteria (p < 0.05), highlighting the critical role of microbial communities in DOM transformation. Partial least squares structural equation modeling (PLS-SEM), a latent variable approach integrating multiple regression analysis, demonstrates that DOM composition, along with environmental factors such as salinity, temperature, and nutrient levels, significantly influences microbial diversity and community dynamics in the lake. These findings highlight the importance of seasonally adjusting management strategies – such as controlling nutrient inputs, monitoring water quality, and managing sediments – to protect key microbial communities and sustain ecosystem health.

42. 题目: Endogenous Mn/Fe biochar derived from algae-rich floc sludge for enhanced peroxymonosulfate activation: Improved surface collision oxidation and role of synergic path
文章编号: N25010901
期刊: Chemical Engineering Journal
作者: Yanli Kong, Feng He, Sha Li, Zhonglin Chen, Jiangya Ma
更新时间: 2025-01-09
摘要: Flocs sludge disposal and resource recycling are now global issues. In this study, a novel biochar activator (FeMn-NBCK) with multi-active sites and more persistent free radicals (PFRs) was synthesized using algae-rich floc sludge as a raw material. FeMn-NBCK possessed an efficient activation for peroxymonosulfate (PMS) to achieve rapid degradation for pollutants. Results showed that the removal rate of 10 mg/L BPA reached 100 % within 20 min by the FeMn-NBCK/PMS system with the reaction rate constant K_obs was 0.1309 min⁻¹. The captured and adsorption PMS on FeMn-NBCK surface to form surface-activated PMS with high potential, collided with surrounding organic pollutants and directly grabbed electron from them to complete pollutant oxidation, making the biochar proposed more effective activation performance through more reactive oxygen species (ROSs), active sites and enhanced electron transfer. And the endogenous Fe/Mn from enhanced coagulation and the rich N/C elements contained in algae made the FeMn-NBCK improved surface collision oxidation path during PMS activation process. Fe/Mn reduced the energy barrier of O-O bond cleaving of PMS, and the presence of Mn provided more electrons, enhanced the electron transport and PMS adsorption at the –CO-Mn sites, making to produce more ROSs. The formation of more persistent free radicals (PFRs) not only acted as active sites, but also facilitated the cleavage of O-O bonds and promoted the formation of free radicals. Furthermore, FeMn-NBCK exhibited good reusability and applicability in water purification. This work would make significant contributions to the utilization of solid waste and the development of biochar in the future.

43. 题目: A review of the conversion of wood biomass into high-performance bulk biochar: Pretreatment, modification, characterization, and wastewater application
文章编号: N25010815
期刊: Separation and Purification Technology
作者: Yu Zhang, Xiuxiu Zhang, Zhenxing Zhou, Gonggang Liu, Chongqing Wang
更新时间: 2025-01-08
摘要: Biochar derived from waste biomass gains increasing global attention due to unique properties such as abundant resources, low cost, and environmental friendliness. Wood biomass from lignocellulosic biomass is an excellent precursor of carbon materials due to its unique natural structure. This review focuses on the main processes of converting wood biomass into high-performance bulk biochar. Pretreatment can improve the availability of biomass and create more pore structures. The main thermochemical techniques are pyrolysis, hydrothermal carbonization, and catalytic graphitization. The modification process is critical in the preparation of high-performance bulk biochar. Combined with the unique structure of wood biomass, activation is effective in further improving the surface area and pore structure of the bulk biochar. The effects of heteroatomic doping and metal loading modifications on the catalytic and adsorptive effects of the bulk biochar are significant. The structure and properties of biochar can be recognized based on various characterization techniques, which provide a reference for targeted biochar applications. Modified biochar, a dual-functional material with adsorption and catalysis, has shown extraordinary performance in wastewater treatment.

44. 题目: Removal of Pb2+from Aqueous Media by Solidago canadensis L.-Derived and Crab Shell-Derived Biochar: Adsorption Behavior and Optimization of Adsorption Conditions
文章编号: N25010814
期刊: Water, Air, & Soil Pollution
作者: Shuyu Ye, Xinyu Jiang, Yirong Yang, Xuemin Xu, Chenhao Zhao, Jinzhao Ma, Wan Yang, Longfei Liu
更新时间: 2025-01-08
摘要:

Pb²⁺, as a heavy metal ion, has been recognized for its strong toxicity and imperative removal from industrial wastewater. In pursuit of resource efficiency, this study employed biochars preparate by limited-oxygen pyrolysis at elevated temperatures, using Solidago canadensis L. (SC) and discarded crab shells (CS) as raw materials. The objective was to investigate the adsorption behaviors and capacities of the resultant biochars for Pb²⁺. Response Surface Methodology (RSM) was utilized to optimize the environmental conditions for the adsorption of Pb²⁺ by the biochars. Adsorption kinetics indicated that Pb²⁺ primarily adhered to the biochar via chemical bonding. Isotherm analysis revealed that Pb²⁺ was fixed by biochar through monolayer adsorption, with the CS-700 demonstrating superior adsorption capacity (93.29 mg/g). The adsorption mechanisms of Pb²⁺ by SC biochar and CS biochar involved complexation, precipitation, electrostatic attraction, and pore filling. Moreover, the solution pH influenced the adsorption efficiency by altering the speciation of Pb²⁺, while the concentration of dissolved organic carbon showed a biphasic effect, initially enhancing and then diminishing the adsorption capacity of CS-700 for Pb²⁺. RSM can accurately predict the removal rate of Pb²⁺by CS-700 under different environmental conditions. For the given adsorption system, the optimal conditions for the removal of Pb²⁺ by CS-700 were achieved at a solution pH of 8.65, with an adsorbent dosage of 0.019 g, and a dissolved organic carbon concentration of 11.85 mg/L. This research provides a valuable approach for the recycling of waste materials and the remediation of heavy metals in contaminated water.

45. 题目: Reconciling Archean organic-rich mudrocks with low primary productivity before the Great Oxygenation Event
文章编号: N25010813
期刊: Proceedings of the National Academy of Sciences of the United States of America
作者: Noam Lotem, Birger Rasmussen, Jian-Wei Zi, Sarah S Zeichner, Theodore M Present, Yinon M Bar-On, Woodward W Fischer
更新时间: 2025-01-08
摘要: The organic carbon content of ancient rocks provides a fundamental record of the biosphere on early Earth. For over 50 y, the high organic content of Archean (>2.5 Ga) mudrocks has puzzled geologists and evolutionary biologists, because high biological primary productivity was unexpected for the nascent biosphere before the rise of O 2 . Here, we took a different approach to resolve this apparent paradox, by studying the accumulation rates of Archean organic-rich mudrocks. We evaluated the sedimentation rates of three sections of the Mount McRae Shale and Jeerinah Formation (2.68 to 2.48 Ga, Pilbara Craton, Australia) with new and recently published U–Pb zircon ages from intraformational ash beds. For comparison, we compiled Phanerozoic (<500 Ma) data from comparable depositional settings and developed an idealized model that considers the sedimentation rates for predicting rock organic content. We found that organic-rich Archean mudrocks were deposited under exceptionally low sedimentation rates (~1 m/Ma), in sharp contrast to organic-rich rocks from the Phanerozoic Eon (10 to 100 m/Ma). Constrained by observations, model results indicated that the Archean data reflect low primary productivity (~100-fold lower than during the Phanerozoic) and enhanced preservation under anoxic conditions, with the principal control on organic carbon content provided by dilution with inorganic sediment. Thus, the high organic carbon content which is typically attributed to high productivity instead reflects slow accumulation, high preservation, and minimal inorganic dilution—reconciling the geological evidence with a slow carbon cycle cadence during Archean time.

46. 题目: High Molecular-Weight Organics as Precursors for Toxic Iodinated Disinfection Byproducts during Chloramination
文章编号: N25010812
期刊: Environmental Science & Technology
作者: Wenyuan Yang, Tom Bond, Chao Fang, Zhenqi Du, Wenhai Chu
更新时间: 2025-01-08
摘要: Iodinated DBPs (I-DBPs), many more toxic than regulated chlorinated and/or brominated DBPs, are a major challenge in the supply of safe drinking water. While over 800 DBPs have been identified, the occurrence and precursors of toxic I-DBPs remain poorly understood. Herein, natural organic matter from two raw drinking waters was fractionated using ultrafiltration membranes into different groups based on molecular weight (MW). The <1 kDa fraction exhibited the highest levels of cytotoxicity and genotoxicity after disinfection. However, in the presence of iodide, the 10–100 kDa fraction had the highest toxicity/dissolved organic carbon values. FT-ICR MS analysis showed high reactivity between hypoiodous acid and the 10–100 kDa fraction, and a shift from aromatic and unsaturated molecules to more saturated and oxidized molecules during chloramination of 10–100 kDa fraction. Based on nontarget analysis using orbitrap MS, four I-DBPs with high peak intensities during chloramination of 10–100 kDa fraction were identified and then confirmed using chemical standards: 4-hydroxy-3-iodo-5-nitrobenzonitrile, 2,4,5-triiodoimidazole, 3,5-diiodo-4-hydroxybenzonitrile, and 2,6-diiodo-4-nitrophenol. The first two have been first identified in drinking water. The concentrations of the four DBPs ranged from <LOD to 20.7 ng/L in the finished waters and tap waters. Moreover, the four I-DBPs were 2–3 orders of magnitude more toxic than regulated tribromomethane and dichloroacetic acid. Overall, our study highlights the 10–100 kDa fraction of high molecular weight organics as the primary precursor group for toxic I-DBPs during chloramination and provides insights into key research challenges for this important category of DBPs.

47. 题目: A new perspective toward sludge biochar with adsorbed heavy metals for cement mortar production
文章编号: N25010811
期刊: Environmental Technology & Innovation
作者: Guangyu Shi, Hao Xu, Jingwen Huang, Feiyue Qian, Lingzhao Kong, Yuqing Huang
更新时间: 2025-01-08
摘要: This study presents a new perspective toward the effect of waste sludge as cement sand material on the mechanical strength and thermal insulation properties of the resulting cement mortar. Herein, sludge biochar waste (NBC), capable of adsorbing zinc (Zn) and copper (Cu), was used as a raw material. Its crushed form with adsorbed Zn and Cu (SBC) was used to replace cement in powder form, and cement mortar was prepared at different dosages (1–8 %) of SBC specimens obtained under different firing temperatures (300–600 °C). The findings revealed that NBC, prepared through pyrolysis at 500 °C, exhibited the highest adsorption capacity and possessed excellent water separation capabilities; and the mechanical strength of the cementitious sand specimens prepared at 5 % SBC dosage was found to be the best, with the flexural and compressive strengths of 8.6 and 36.17 MPa, respectively. These values were significantly higher than those of the control group (5.91 and 25.63 MPa, respectively). Furthermore, with the increase in the SBC dosage, a notable enhancement in the specific heat capacity of the cement mortar was observed, which was accompanied by a reduction in its thermal conductivity, resulted in the composite material displaying improved thermal storage and insulation performance. The leaching test confirmed that the incorporation of biochar significantly enhanced the immobilization of heavy metals (namely Cu, Zn, Cd, Cr, Pb, and Ni) in the mortar material, achieving an immobilization rate exceeding 99 %. Instrumental analyses revealed that alkaline porous biochar facilitated and extended the hydration reaction, resulting in the formation of additional cementitious materials such as hydrated calcium silicate and calome. This study introduces a novel approach for the synergistic immobilization of biochar and heavy metals, thereby transforming municipal sludge into a valuable resource.

48. 题目: Terrestrial organic matter input changes recorded by biomarkers alter phosphorus burial in the upper Yangtze River Basin
文章编号: N25010810
期刊: Environmental Earth Sciences
作者: Yan Chen, Zihan Zhao, Yanqin Zhang, Zhipeng Yao, Yanhua Wang
更新时间: 2025-01-08
摘要:

Exploring the impacts of anthropogenic processes on the organic matter (OM) input and phosphorus (P) burial characteristics is essential for describing the carbon (C) cycle and its environmental effects on aquatic ecosystems from multiple perspectives. In this study, the centennial sedimentary P, C, and nitrogen (N) characteristics and terrestrial OM input changes in the upper Yangtze River were reconstructed by ²¹⁰Pb-dated and positive matrix factorization (PMF) methods, and the key factors were identified. The P accumulation and stock averaged at 2.23 ± 1.08 g P m⁻² yr⁻¹ and 0.01–0.07 Mg P ha⁻¹ from 1855 to 2019. Changes in corresponding loads of total organic C (TOC) and N (TN) separately ranged between 0.58 and 1.81 Mg C ha⁻¹ and 0.07–0.29 Mg N ha⁻¹ over the past century. The total sequestration was 4.20 × 10⁵ t of C, 5.51 × 10⁴ t of N, and 1.22 × 10⁴ t of P, respectively, accounting for 33%, 54%, and 14% of Dianchi Lake. The strength and contribution of terrestrial OM driven by anthropogenic activities were constantly increased, and the proportion increased sharply from 34 to 52%. About 67–86% of biogenic OM was the main source of P sedimentation. In the context of recent warming, the combined effects of C and N loading, redox environment, climate change, and anthropogenic activities enhanced the P accumulation and retention by 1.29 g P m⁻² yr⁻¹ per 1 ℃ increase in temperature. These findings suggest that the sediment in this area generally acts as a sink pool of nutrients, which is critical for predicting P fate and nutrient cycle.

49. 题目: Phenol–Quinone Redox Couples of Natural Organic Matter Promote Mercury Methylation in Paddy Soil
文章编号: N25010809
期刊: Environmental Science & Technology
作者: Yao Huang, Yingmei Huang, John R Reinfelder, Huan Zhong, Liping Fang, Chuanping Liu, Fangbai Li
更新时间: 2025-01-08
摘要: Methylmercury in paddy soils poses threats to food security and thus human health. Redox-active phenolic and quinone moieties of natural organic matter (NOM) mediate electron transfer between microbes and mercury during mercury reduction. However, their role in mercury methylation remains elusive. Here, artificial organic matter (AOM), i.e., biochar, wherein the phenol–quinone ratio and associated redox properties varied, was used as a redox-tunable model NOM to investigate the impact of the phenol–quinone redox couples on mercury methylation in Hg-contaminated paddy soils. Our findings confirm that AOM with higher phenol–quinone ratios (i.e., electron donor capacities) stimulated microbial methylation (4.9-fold increase) and dark abiotic methylation (2.2-fold increase). The phenol–quinone ratio had contrasting effects on the abundance of the Hg methylation gene hgcA and metabolic genes corresponding to Hg-methylating and demethylating clades (i.e., dsrA, dsrB, mcrA, and pmoA), especially under anaerobic (simulated flooding) conditions. The key Hg methylators were from Geobacteraceae, including Oryzomonas, Fundidesulfovibrio, and Geomobilimonas. The microbial methylation driven by the phenol–quinone ratio was further validated by NOM such as humic and fulvic acids. Notably, abiotic methylation was observed in aerobic sterilized soil, yet additional evidence is necessary to confirm the potential abiotic pathway, hampered by the difficulty of identifying effective methyl donors in soil. Our results reveal the potential of phenol–quinone redox properties in NOM to drive mercury methylation, offering novel insights into mercury methylation in paddy soils.

50. 题目: A landscape-scale view of soil organic matter dynamics
文章编号: N25010808
期刊: Nature Reviews Earth & Environment
作者: Sebastian Doetterl, Asmeret Asefaw Berhe, Katherine Heckman, Corey Lawrence, Jörg Schnecker, Rodrigo Vargas, Cordula Vogel, Rota Wagai
更新时间: 2025-01-08
摘要:

Soil carbon is an important component of the terrestrial carbon cycle and could be augmented through improved soil management to mitigate climate change. However, data gaps for numerous regions and a lack of understanding of the heterogeneity of biogeochemical processes across diverse soil landscapes hinder the development of large-scale representations of soil organic matter (SOM) dynamics. In this Perspective, we outline how understanding soil formation processes and complexity at the landscape scale can inform predictions of soil organic matter (SOM) cycling and soil carbon sequestration. Long-term alterations of the soil matrix caused by weathering and soil redistribution vary across climate zones and ecosystems, but particularly with the structure of landscapes at the regional scale. Thus, oversimplified generalizations that assume that the drivers of SOM dynamics can be scaled directly from local to global regimes and vice versa leads to large uncertainties in global projections of soil C stocks. Data-driven models with enhanced coverage of underrepresented regions, particularly where soils are physicochemically distinct and environmental change is most rapid, are key to understanding C turnover and stabilization at landscape scales to better predict global soil carbon dynamics.

51. 题目: Shaping rhizocompartments and phyllosphere microbiomes and antibiotic resistance genes: The influence of different fertilizer regimes and biochar application
文章编号: N25010807
期刊: Journal of Hazardous Materials
作者: Kedi Li, Saeed ur Rahman, Asad Rehman, Haoxiang Li, Nan Hui, Muhammad Khalid
更新时间: 2025-01-08
摘要: Understanding the impact of different soil amendments on microbial communities and antibiotic resistance genes (ARGs) dissemination is crucial for optimizing agricultural practices and mitigating environmental risks. This study investigated the effects of different fertilizer regimes and biochar on plant-associated bacterial communities and ARGs dissemination. The biochar's structural and chemical characteristics were characterized using scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy, revealing a porous architecture with diverse functional groups. The presence of ARGs varied significantly across groups, with manure-treated samples exhibiting the greatest diversity and abundance, raising concerns about ARGs dissemination. Soil enzyme activities responded differently to treatments; manure significantly enhanced catalase, acid phosphatase, and urease activities, whereas saccharase was most responsive to chemical fertilizer. These differences are possibly responsible for the distinct microbiome structure associated with the plant's root system. The analysis of bacterial diversity and richness across rhizocompartments and the phyllosphere highlighted that manure-treated rhizospheres and phyllospheres displayed the highest species richness and diversity. Notably, Proteobacteria dominated across most treatments, with distinct shifts in bacterial phyla and genera influenced by manure and biochar applications. The LEfSe analysis identified key indicator genera specific to each group, indicating that both fertilizer type and biochar application significantly shape microbial community composition. Co-occurrence network analysis further demonstrated that manure and biochar treatments created unique microbial networks in the rhizosphere, rhizoplane, phyllosphere, and endosphere, highlighting the role of these amendments in modulating microbial interactions in plant-associated environments. These findings suggest that manure, while enhancing microbial diversity and soil enzyme activities, also increases ARGs, whereas biochar may not contribute to the spread of ARGs and fosters distinct microbial communities, offering valuable insights for sustainable agricultural practices.

52. 题目: Organic matter DYnamic model (OMDY) predicts the wood debris decomposition of ten Mediterranean species
文章编号: N25010806
期刊: Plant and Soil
作者: Sabrina Spigno, Fabrizio Cartenì, Mohamed Idbella, Alfonso Piscitelli, Michele Staiano, Silvana Cangemi, Riccardo Spaccini, Stefano Mazzoleni, Giuliano Bonanomi, Francesco Giannino
更新时间: 2025-01-08
摘要:

Backgrounds and Aims

Forest litter is mainly composed by leaves, roots and wood debris (WD) residues. WD decomposition in Mediterranean ecosystems has received less attention compared to other materials and to boreal, tropical and temperate biomes. The OMDY model describes organic matter decomposition using ¹³C NMR spectroscopy.

Methods

The mass loss and the ¹³C NMR of ten mediterranean wood and shrub species were monitored for a long-term (5 years) experiment. The regularized generalized regression LASSO was used to select the NMR spectra regions more predictable for the WD decomposition. The OMDY model was applied to simulate the long-term decomposition experiment of ten mediterranean wood and shrub species.

Results

WD species, chemical composition and decomposition time significantly influenced the dynamics of the remaining mass during the decomposition. The NMR analysis revealed an increase in alkyl C and carbonyl C while a decrease in di-O-alkyl C and O-alkyl C. Pistacia lentiscus L. showed the highest decomposition, with a O-alkyl C declining and alkyl C rising. Erica arborea L. decomposed less, showing smaller decreases in O-alkyl C, lower alkyl C accumulation. The LASSO method identified three chemical regions as crucial for WD decomposition. The OMDY model, using as input these NMR molecular regions, demonstrated a high capacity to describe long-term WD decomposition.

Conclusions

The model is adaptable to describe the decomposition of wood. The results show that the model is general, as NMR can describe different materials' spectra and ordinary differential equations predict their reduction.

53. 题目: Soil aggregation alterations under soil microplastic and biochar addition and aging process
文章编号: N25010805
期刊: Environmental Pollution
作者: Haixiao Li, Longyuan Yang, Chenghui Luo, Le Liu, Cheng Li, Ji Wang, Wei Qiao, Hua Zhong
更新时间: 2025-01-08
摘要: Soil microplastics (MPs) are a substantial threat to soil health, particularly by disrupting soil aggregation. Additionally, MPs undergo aging processes in the soil, which may significantly alter their long-term impacts on soil structure. To investigate these effects, we conducted an eight-month soil incubation experiment, examining the influence of MPs and their aging on soil aggregation. The experiment utilized a factorial design with various combinations of MPs and biochar additions: 1% by weight of 1000-mesh polyethylene and polypropylene MPs, and 5-mm biochar, resulting in six treatment groups: [CK], [PE], [PP], [Biochar], [PE + biochar], and [PP + biochar]. Our findings revealed that both MPs and biochar underwent aging throughout the incubation, evidenced by the formation of oxygen-containing functional groups on their surfaces. Microplastics, particularly polyethylene, primarily affected the 0.5–1 mm and >2 mm aggregate fractions, with average reductions of 21% and 77%, respectively. These adverse effects intensified with the aging of MPs. Contrary to expectations, the addition of biochar was found to exacerbate the negative impacts of MPs on the 0.25–0.5 mm aggregates, with a decrease of 11% associated with PE MPs. The influence of biochar on mitigating the damage caused by MPs to soil aggregation is dependent on aggregate size.

54. 题目: Visible light-driven selective oxidation of multiple organic matters by photocatalysis of BiOX (X = I, Br): New insights into the role of oxygen vacancy generation and electron gain/loss properties of matter
文章编号: N25010804
期刊: Separation and Purification Technology
作者: Jingyuan Yan, Jingwei Zhang, Yue Wang, Jianlin Lv, Hanbing Zhang, Zhangfa Tong, Yingqi Yu, Kun Liu
更新时间: 2025-01-08
摘要: Realizing better photocatalytic activity of materials by various strategies has always been a hot topic in the field of environmental catalysis. However, the complex heterogeneous composition and preparation process of catalysts undoubtedly limit their potential for practical pollution control. Therefore, clarifying the selective photocatalytic mechanism of pristine semiconductor oxide and the crucial relationship between catalysts structures and physical–chemical characteristics of target pollutants become more necessary. In our study, based on the combination of density functional theory (DFT) calculation and characterizations, the differences in photocatalytic degradation behavior and intrinsic mechanisms of common organic pollutants including ciprofloxacin (CIP), tetracycline (TC), Rhodamine B (RhB) and bisphenol-A (BPA) over the pristine BiOBr and BiOI were investigated, thereby clarifying the crucial relationship and synergistic effects between photocatalysts microstructure and pollutants characteristics. Under the same reaction conditions, 10 %-BiOBr (BiOBr obtained from the hydrothermal treatment in a 10 % ethylene glycol solution environment) exhibited better degradation performance of CIP (73 %), TC (67 %) and RhB (95 %) than that of BPA (28 %). While 10 %-BiOI (BiOI obtained from the hydrothermal treatment in a 10 % ethylene glycol solution environment) exhibited better degradation performance of BPA (88 %) than those of CIP (27 %), TC (60 %) and RhB (41 %). The obvious selective degradation difference of various target pollutants over the 10 %-BiOBr and 10 %-BiOI could be ascribed as follows: (i) Under the same synthesis conditions, the differences in BiO bond lengths due to the halogen layer resulted in BiOI being more susceptible to generate oxygen vacancy than BiOBr under the same catalyst preparation condition, thereby boosting the non-free radicals degradation of electron-rich pollutants. (ii) The generation of free radicals and non-free radicals during photocatalysis were directly affected by the electronic characteristic discrepancies of the pollutants, thereby changing the main degradation pathway of organic matters. Results indicated that the electron-deficient pollutants including CIP, TC and RhB tended to be degraded by free radicals pathway. On the contrary of that electron-rich pollutants BPA was more susceptible to degradation via direct electrons transfer to oxygen vacancies of 10 %-BiOI. Our study supplied new insight into adopt pristine photocatalysts based on the difference of oxygen vacancy for selectively degrading various pollutants with different donating/losing electron ability, the corresponding mechanisms and degradation pathway could provide theoretical reference for practical application of pristine photocatalysts.

55. 题目: A review of the current status of nitrogen self-doped biochar applications
文章编号: N25010803
期刊: Journal of Environmental Chemical Engineering
作者: Guanbiao Ruan, Yuehong Yang, Xiaoling Peng, Junya Wang, Yongkang Guo, Weiyao Hu, Daozhao Lin
更新时间: 2025-01-08
摘要: Pristine biochar tends to be poorly structured and with limited active sites, inhibiting its commercial utilization. To expand the adsorption range of biochar and improve its adsorption properties and activity, functionalization with N-related groups has been proposed. However, nitrogen self-doped biochar is a material that is itself enriched with carbon and nitrogen and can be prepared from a variety of feedstocks based on animals, plants, food, algae, organic wastes, proteins/amino acids, fungi, and others. The nitrogen-containing functional groups of biochar hold the promise of a wide range of applications such as pollutant adsorption, catalytic adsorption, and energy storage. To date, many methods have been developed and used to enhance the functionality of nitrogen-containing biochar for its application and commercialization. However, there are few reviews related to the development and application of nitrogen self-doped biochar technology. The presence of N-functional groups on the surface of biochar enhances the alkalinity of the carbon surface, promotes electrostatic interactions, and facilitates the structural properties of the biochar, providing a larger interaction region, nowadays N-biochar is widely used in several fields. This paper reviews the research progress in the preparation, activation, and role played in the application of common N-doped biochar in recent years, as well as the biomasses that can be used as references for the production of nitrogen self-doped biochar. Finally, challenges and prospects for the application of nitrogen self-doped biochar in several fields are presented.

56. 题目: Photic versus Aphotic Production of Organohalogens from Native versus Invasive Wetland Plants-Derived Dissolved Organic Matter
文章编号: N25010802
期刊: Water Research
作者: Yu Fu, Xueqi Hu, Pu Wang, Qingchao Li, Lingli Wang, Jialin Chen, Zhaohui Wang
更新时间: 2025-01-08
摘要: The aphotic formation of natural organohalogens (NOHs) remains inadequately understood, in contrast to the well-documented photo-halogenation process of dissolved organic matter (DOM), despite the significant biogeochemical implications associated with NOHs. This study investigates the differences in the formation of chlorinated and brominated compounds from the photochemical and aphotic reactions of native Phragmites australis (PA-DOM) and invasive Spartina alterniflora (SA-DOM). The findings indicate that SA-DOM exhibits a greater potential for photochemical halogenation, attributed to its higher aromatic content and enhanced photostability. Utilizing advanced mass spectrometry, the study identifies nitrogen-containing and free saturated compounds as primary precursors for both types of DOM during photochemical halogenation. Notably, significant disparities in the halogenation processes of lignin/CRAM, nitrogen-containing/free saturated compounds, and amino sugars between SA-DOM and PA-DOM are observed, leading to a higher production of NOHs in PA-DOM during aphotic reactions compared to photic reactions, even in artificial seawater. Furthermore, the study emphasizes the critical role of dissolved oxygen in the formation of NOHs from PA-DOM under aphotic conditions. Given the rapid fluctuations in oxygen levels, salinity, and solar intensity, alongside tidal and diurnal cycles, the significance of both photic and aphotic pathways for NOHs formation should not be overlooked.

57. 题目: Organic matter and biomarkers: Why are samples required?
文章编号: N25010801
期刊: Proceedings of the National Academy of Sciences of the United States of America
作者: Mark A Sephton, Andrew Steele, Frances Westall, Florence Schubotz
更新时间: 2025-01-08
摘要: The search for evidence of past prebiotic or biotic activity on Mars will be enhanced by the return of samples to Earth laboratories. While impressive analytical feats have been accomplished by in situ missions on the red planet, accessing the capabilities of Earth’s global laboratories will present a step change in data acquisition. Highly diagnostic markers of past life are biomarkers, organic molecules whose architecture can be attributed to once living organisms. Similar organic molecular structures can also be used to identify the prebiotic steps that preceded any emergence of life. The style of modification or degradation of such organic structures indicates their agents of change, including oxidants, radiation, heating, water, and pressure. For biomarker analysis, sample return provides enhanced opportunities for sample preparation and analyte isolation. The augmentation of biomarker data with spatial information provides the opportunity for confirmatory data but is a multistep and multitechnique process best achieved here on Earth. Efficient use of returned samples will benefit from lessons learned on Earth’s ancient records and meteorites from Mars. The next decade is a time when analytical capabilities can be improved as we prepare for the delivery of carefully selected and collected extraterrestrial samples containing potential evidence of the development or even emergence of past life on Mars.

58. 题目: Thermodynamics of Microbial Decomposition of Persistent Carbon in Erosion-Buried Topsoils
文章编号: N25010710
期刊: Soil Biology and Biochemistry
作者: A D Mitchell, Helgason B.L
更新时间: 2025-01-07
摘要: Hillslope erosion in hummocky landscapes can lead to the accumulation of C-rich topsoil in depositional positions that eventually becomes buried if erosion persists. Our objective in this study was to evaluate the persistence of SOC and the thermodynamic efficiency of the microbial community in C-rich buried surface horizons from five sites with varied texture and organic matter contents. Surface Ah (0-10 cm) and buried surface (Ahb) horizons were isolated from intact cores, sieved (<2 mm) and incubated under ideal conditions of temperature and moisture. Ahb soils had an average organic C content (25.6 mg OC g^-1 soil) similar to the corresponding Ah soil (30.9 mg OC g^-1 soil). Using isothermal calorimetry, we determined that Ah horizons produced significantly more heat and CO₂ but had smaller calorespirometric ratios than Ahb soils, under both basal (841 vs 3106 kJ mol^-1 CO₂-C) and glucose metabolism (627 vs. 697 kJ mol^-1 CO₂-C).100-day basal respiration was nearly four times greater in Ah vs. Ahb horizons. While MAOM correlated with basal heat production in both horizons, it only correlated with C persistence in the Ah horizons (Rho = 0.67, p < 0.01), suggesting variability in C persistence was not primarily driven by organo-mineral bonds in Ahb horizons, although energy use efficiency is. Microbial community structure in Ahb horizons was distinct from the surface soils, and changed minimally during incubation, suggesting co-development of the community as decomposition proceeded over the decades of burial, leading to persistent C. These relatively large volume buried surface soils may provide unique opportunities to understand microbial hotspot C processes that are typically difficult to isolate at a spatially explicit scale (e.g., an aggregate interior). We propose that the co-development of distinct microbial communities in C-rich buried horizons leads to more thermally stable SOC, but further research is required to test this hypothesis.

59. 题目: Ocean acidification and global warming may favor blue carbon service in a Cymodocea nodosa community by modifying carbon metabolism and dissolved organic carbon fluxes
文章编号: N25010709
期刊: Marine Pollution Bulletin
作者: Alba Yamuza-Magdaleno, Rocío Jiménez-Ramos, Javier Cavijoli-Bosch, Fernando G Brun, Luis G Egea
更新时间: 2025-01-07
摘要: Ocean acidification (OA) and global warming (GW) drive a variety of responses in seagrasses that may modify their carbon metabolism, including the dissolved organic carbon (DOC) fluxes and the organic carbon stocks in upper sediments. In a 45-day full-factorial mesocosm experiment simulating forecasted CO2 and temperature increase in a Cymodocea nodosa community, we found that net community production (NCP) was higher under OA conditions, particularly when combined with warming (i.e., synergistic effect). Moreover, under OA conditions, an increase in aboveground biomass and photosynthetic shoot area was recorded. Interestingly, DOC fluxes were reduced when exposed to OA; however, an increase occurred when both factors acted together (i.e., antagonistic effect), which was attributable to increased DOC release by plants. Our results suggest that C. nodosa populations in temperate latitude may favor blue carbon service in future scenarios of OA and GW by increasing the NCP, the DOC export with lower labile:recalcitrant ratio, and accumulating more organic carbon in upper sediments. These findings offer additional arguments for the urgent need to protect and conserve this valuable ecosystem.

60. 题目: Molecular-level characterization of supraglacial dissolved and water-extractable organic matter along a hydrological flow path in a Greenland Ice Sheet micro-catchment
文章编号: N25010708
期刊: Biogeosciences
作者: Eva L Doting, Ian T Stevens, Anne M Kellerman, Pamela E Rossel, Runa Antony, Amy M McKenna, Martyn Tranter, Liane G Benning, Robert G M Spencer, Jon R Hawkings, Alexandre M Anesio
更新时间: 2025-01-07
摘要: . Sunlight penetrates the bare-ice surface of glaciers and ice sheets, giving rise to the presence of a three-dimensional porous matrix of partially melted ice crystals known as the weathering crust. Surface meltwater slowly percolates through this weathering crust, which hosts active and diverse bacterial communities, until it reaches a supraglacial stream. Despite the potential implications of weathering crust dynamics for glacial melting and the export of carbon and nutrients to downstream ecosystems, its role in biogeochemical cycling remains unknown. Here, we use Fourier transform cyclotron resonance mass spectrometry to characterize dissolved organic matter (DOM) along a meltwater flow path in a hydrologically connected micro-catchment on the southern Greenland Ice Sheet. We find a decrease in the relative abundance of aromatic formulae from surface ice (24.9 ± 2.8 %) to weathering crust meltwater (3.5 ± 0.3 %) to supraglacial stream water (2.2 ± 0.2 %), pointing towards photodegradation of aromatic DOM during supraglacial meltwater transit. The relative abundance of aliphatic and peptide-like formulae in supraglacial stream DOM was lower (38.5 ± 4.0 %) than in weathering crust meltwater DOM (50.3 ± 2.4 %), likely as a result of microbial respiration of labile compounds within the weathering crust. Hence, we conclude that the weathering crust plays a thus far unexplored role in supraglacial biogeochemical cycling. In addition, we characterize water-extractable organic matter isolated from surface ice particulate matter, which was predominantly (61.6 ± 8.1 % relative abundance) comprised of aliphatic and peptide-like formulae, providing the first direct evidence of surface ice particulate matter as a potential source of biolabile DOM. As the spatial extent of bare-ice surfaces and the associated weathering crust photic zone is set to increase under a warming climate, our findings underscore the pressing need to further evaluate the role of the weathering crust in supraglacial biogeochemical processes. An understanding of weathering crust biogeochemical cycling is especially critical as climatic warming is predicted to lead to an increase in Arctic rainfall, consequently increasing the frequency of weathering crust degradation events, with unknown impacts on the export of supraglacial DOM to downstream ecosystems.