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101. 题目: Mechanistic Insight into Multiple Effects of Copper Ion on the Photoreactivity of Dissolved Organic Matter
文章编号: N25010509
期刊: Journal of Hazardous Materials
作者: Zhansheng Li, Hongxia Zhao, Jitao Lv, Shafiul Azam
更新时间: 2025-01-05
摘要: Sunlight irradiation of dissolved organic matter (DOM) in surface water results in the production of photochemically produced reactive intermediates (PPRIs). This process is inevitably influenced by co-existing metal ions in aquatic environments; However, the underlying mechanism remains unclear. In this study, the effect of co-existing copper ion (Cu²⁺) on PPRIs produced by irradiation of DOM was systematically investigated, because Cu²⁺ is a typical redox transient cation and has strong affinity to DOM. The findings demonstrated that Cu²⁺, acting as cation bridge, caused DOM to aggregate, and had impacts on the optical properties and conformation of DOM. The electron shuttle and catalyst effect of Cu²⁺ could accelerate the charge transfer processes for the increasing of quantum yield and steady concentrations of hydroxyl radical (·OH) with the increase of concentrations of e^-_aq, O₂^.-, hydrogen peroxide (H₂O₂) and charge separated states of DOM (DOM^·+ or DOM^·-); On the other hand, Cu²⁺, as excited state quencher, decrease of apparent quantum yield of triplet state of DOM (³DOM^⁎) and singlet oxygen (¹O₂) through static quenching of singlet excited of DOM (¹DOM^⁎) and dynamic quenching of ³DOM^⁎, respectively. The results provide a deeper understanding of the effect mechanism of Cu²⁺ on the DOM photochemistry in real environment and will be useful for assessment the photodegradation of organic contaminants in the presence of both DOM and Cu²⁺.

102. 题目: Impacts of Spartina alterniflora invasion on soil carbon components of particulate and mineral-associated organic matter and soil organic matter mineralization in estuarine wetlands
文章编号: N25010508
期刊: Applied Soil Ecology
作者: Lin Wang, Yuan Li, Jie Hei, Weiqi Wang, Jordi Sardans, Zhihao Zhang, Fanjiang Zeng, Maoquan Ge, Yiyang Liao, Yunying Fang, Tony Vancov, Jiawei Gan, Zhaoliang Song, Weidong Zhang, Josep Peñuelas
更新时间: 2025-01-05
摘要: Estuarine wetlands are critical global carbon sinks, significantly influencing the climate through carbon cycling. The invasive plant Spartina alterniflora has earned attention for its effects on these processes in wetland ecosystems. This study examines the impact of S. alterniflora on soil carbon dynamics in the Minjiang River estuarine wetland, Fujian Province, by comparing soil organic carbon (SOC) components in particulate organic matter (POM) and mineral-associated organic matter (MAOM) between S. alterniflora and native Cyperus malaccensis stands. We also investigated soil carbon dioxide (CO2) emissions and organic carbon mineralization to assess how plant invasion alters carbon cycling in wetland soils. The invasion of S. alterniflora increased dissolved organic carbon (DOC), microbial biomass carbon (MBC), and labile organic carbon (LOC) in MAOM while reducing these carbon components in POM. LOC and MBC contents in MAOM were 15 % and 32 % higher, respectively, in S. alterniflora wetlands compared to C. malaccensis wetlands. This suggests that S. alterniflora shifts the composition and stability of SOC, making MAOM a more significant carbon pool. The invasion also led to higher CO2 emissions and greater temperature sensitivity. Additionally, S. alterniflora soils exhibited a negative priming effect upon glucose addition, likely due to the strong association between active organic carbon and minerals in MAOM, which protects organic matter from decomposition. These results highlight the intricate impacts of plant invasion on soil carbon cycling and offer insights for predicting carbon dynamics in estuarine wetlands.

103. 题目: Organic carbon dry deposition outpaces atmospheric processing with unaccounted implications for air quality and freshwater ecosystems
文章编号: N25010507
期刊: Science Advances
作者: John Liggio, Paul Makar, Shao-Meng Li, Katherine Hayden, Andrea Darlington, Samar Moussa, Sumi Wren, Ralf Staebler, Jeremy Wentzell, Michael Wheeler, Amy Leithead, Richard Mittermeier, Julie Narayan, Mengistu Wolde, Dane Blanchard, Julian Aherne, Jane Kirk, Colin Lee, Craig Stroud, Junhua Zhang, Ayodeji Akingunola, Ali Katal, Philip Cheung, Roya Ghahreman, Mahtab Majdzadeh, Megan He, Jenna Ditto, Drew R Gentner
更新时间: 2025-01-05
摘要: Dry deposition is an important yet poorly constrained process that removes reactive organic carbon from the atmosphere, making it unavailable for airborne chemical reactions and transferring it to other environmental systems. Using an aircraft-based measurement method, we provide large-scale estimates of total gas-phase organic carbon deposition rates and fluxes. Observed deposition rates downwind of large-scale unconventional oil operations reached up to 100 tC hour −1 , with fluxes exceeding 0.1 gC m −2 hour −1 . The observed deposition lifetimes (τ dep ) were short enough (i.e., 4 ± 2 hours) to compete with chemical oxidation processes and affect the fate of atmospheric reactive carbon. Yet, much of this deposited organic carbon cannot be accounted for using traditional gas-phase deposition algorithms used in regional air quality models, signifying underrepresented, but influential, chemical-physical surface properties and processes. Furthermore, these fluxes represent a major unaccounted contribution of reactive carbon to downwind freshwater ecosystems that outweigh terrestrial sources, necessitating the inclusion of dry deposition in aquatic carbon balances and models.

104. 题目: Effect of a high Cl– concentration on the transformation of waste leachate DOM by the UV/PMS system: A mechanistic study using the Suwannee River natural organic matter (SRNOM) as a simulator of waste leachate DOM
文章编号: N25010506
期刊: Journal of Hazardous Materials
作者: Qingyang Li, Feiyan Fang, Weiming Chen
更新时间: 2025-01-05
摘要: The ultraviolet-activated peroxymosnofulate system (UV/PMS), an effective advanced oxidation process for removing dissolved organic matter (DOM) from wastewater, is limited by high chloride ion (Cl⁻) concentrations in landfill leachate. This study used Fourier transform ion cyclotron resonance mass spectrometry to explore the UV/PMS reaction with DOM in the presence of high Cl⁻. The results revealed that elevated Cl⁻ levels generate reactive chlorine species, including chlorine radicals, dichlorine radicals, and hypochlorous acid/hypochlorite, reducing the total organic carbon (TOC) removal efficiency of Suwannee River natural organic matter (SRNOM) from 79% to 39% at 10,000 mg/L Cl⁻. In the absence of Cl^–, the UV/PMS process removes almost all molecular species from SRNOM and generates aliphatic substances with low oxygen contents. When high concentrations of Cl⁻ are present, it preferentially removes aromatic and highly unsaturated molecules and produces 408 unknown chlorinated DOMs with highly unsaturated and high-oxygen content features, including CHOCl, CHONCl, and CHOSCl species. We find that in the UV/PMS process without Cl⁻, DOM is degraded primarily by dealkylation, decarboxylation, and dearomatization; high concentrations of Cl⁻ impair these reactions, and chlorinated DOM forms via chlorine addition/substitution along with other oxidative reactions.

105. 题目: Rsearch progress on biochar materials for new pollutants removal in the aquatic environment: a mini-review
文章编号: N25010505
期刊: Frontiers of Environmental Science & Engineering
作者: Wulve Fan, Xiaolin Shen, Zhiliang Zhu, Xiaochang Liu, Hua Zhang, Yanling Qiu, Daqiang Yin
更新时间: 2025-01-05
摘要:

Antibiotics, endocrine-disrupting compounds (EDCs), per- and polyfluoroalkyl substances (PFAS), and microplastics (MPs) are crucial constituents of the pollutants frequently detected in various aquatic environments. These pollutants can negatively affect human health and aquatic organisms. To eliminate these new pollutants from water economically and environmentally, biochar is considered an efficient environmental functional material because of its excellent performance. Although numerous studies have reported the concentration, distribution, and removal methods of individual new pollutants, a comprehensive and systematic understanding of biochar-based materials for the removal of multiple new pollutants from aquatic environments remains to be comprehensively explored. Therefore, in this mini-review, recent research progress on biochar materials in the decontamination of new pollutants, including antibiotics, EDCs, PFAS, and MPs in different water sources, is summarized, and different mechanisms and influencing factors during the removal process are discussed to have a profound understanding of the application of biochar in the water environment. Future studies on biochar materials for the removal of new pollutants are indicated to enlighten future exploration and alleviate new pollutant burdens in aquatic environments.

106. 题目: Residual effects of biochar and nano-modified biochar on growth and physiology under saline environment in two different genotype of Oryza sativa L.
文章编号: N25010504
期刊: Journal of Environmental Management
作者: Haider Sultan, Hafiz Muhammad Mazhar Abbas, Mohammad Faizan, Abolghassem Emamverdian, Asad Shah, Saraj Bahadur, Yusheng Li, Mohammad Nauman Khan, Lixiao Nie
更新时间: 2025-01-05
摘要: Soil salinity is represent a significant environmental stressor that profoundly impairs crop productivity by disrupting plant physiological functions. To mitigate this issue, the combined application of biochar and nanoparticles has emerged as a promising strategy to enhance plant salt tolerance. However, the long-term residual effects of this approach on cereal crops remain unclear. In a controlled pot experiment, rice straw biochar (BC) was applied in an earlier experiment at a rate of 20 t/ha, in conjunction with ZnO and Fe2O3 nanoparticles at concentrations of 10 mg L−1 and 20 mg L−1. Two rice genotypes, Jing Liang You-534 (salt-sensitive) and Xiang Liang You-900 (salt-tolerant), were utilized under 0% NaCl (S1) and 0.6% NaCl (S2) conditions. Results showed that, application of residual ZnOBC-20 significantly enhanced rice biomass, photosynthetic assimilation, relative chlorophyll content, SPAD index, enzyme activities, K+/Na+ ratio, hydrogen peroxide (H2O2) levels, and overall plant growth. Specifically, ZnOBC-20 increased the tolerance index by 142.8% and 146.1%, reduced H2O2 levels by 27.11% and 35.8%, and decreased malondialdehyde (MDA) levels by 33% and 57.9% in V1 and V2, respectively, compared to their respective controls. Residual of ZnOBC-20 mitigated oxidative damage caused by salinity-induced over-accumulation of reactive oxygen species (ROS) by enhancing the activities of antioxidant enzymes (SOD, POD, CAT, and APX) and increasing total soluble protein (TSP) content. Xiang Liang You-900 exhibited a less severe response to salinity compared to Jing Liang You-534. Additionally, residual of ZnOBC-20 significantly enhanced the anatomical architecture of both root and leaf tissues and regulated the expression levels of salt-related genes. Residual of ZnOBC-20 also improved salt tolerance in rice plants by reducing sodium (Na+) accumulation and enhancing potassium (K+) retention, thereby increasing the K+/Na+ ratio under saline conditions. The overall results of this experiment demonstrate that, residual effects of ZnOBC-20 not only improved the growth and physiological traits of rice plants under salt stress but also provided insights into the mechanisms behind the innovative combination of biochar and nanoparticles residual impacts for enhancing plant salt tolerance.

107. 题目: Dynamics of microbial communities and organic carbon pools in karst wetland soils
文章编号: N25010503
期刊: Catena
作者: Yutian Xiao, Congyu Cheng, Aoqi Cheng, Weihua Kang, Taiming Shen, Qingrong Yang, Cong Peng, Longjiang Yu, Wei Li
更新时间: 2025-01-05
摘要: Understanding dynamic changes in soil organic carbon (SOC) and microbial communities in karst wetlands is of great importance for the restoration and protection of these environments. The purpose of this study was to characterize the composition and abundance of microbial communities and enzyme activities related to SOC pools in three states of the Huixian karst wetland, representing primary, naturally degraded and human interference conditions (reclaimed cropland). This study employed 16S/ITS2 high-throughput sequencing to characterize the spatiotemporal dynamics of microbial communities. The microbial taxa and enzymes closely associated with variations in SOC pools were analyzed. Significant differences in organic carbon fractions, physicochemical properties, and enzyme activities varied by season and generally showed vertical distribution patterns. The species composition of microbial communities in the three wetland states was broadly similar, but some dominant bacterial species differed significantly in relative abundance. The prokaryotic communities were closely related to changes in organic carbon pools and mainly included Anaeromyxobacter, Bacillus, Bryobacter, Flavisolibacter, Gemmatimonas and Haliangium, of which members of the family Anaeromyxobacteraceae were relatively abundant in reclaimed wetland in summer; Flavisolibacter and Gemmatimonas were relatively abundant in degraded wetland in spring and winter, respectively. Among fungi, Clonostachys, Fusarium, Talaromyces, Conlarium, Westerdykella, Ascobolus, Chaetomium, Polyschema, and Aspergillus were the major taxa closely associated with changes in organic carbon pools. Among them, Fusarium, Talaromyces and Polyschema were relatively abundant in reclaimed wetland in autumn, spring and winter, respectively; Chaetomium and Aspergillus were relatively abundant in degraded wetland in winter and in primary wetland in summer. The enzyme activities closely associated with the variations of organic carbon fractions in karst wetland soils were carbonic anhydrase, sucrase and polyphenol oxidase.

108. 题目: Colloids fractionation and characterization of arsenic (As) and dissolved organic matter (DOM) in surface water around a closed arsenic mine
文章编号: N25010502
期刊: Journal of Hazardous Materials
作者: Zhenzhen Yu, Chaoyang Wei, Fen Yang, Zhiying Li, Bin Jiang, Weijie Dai, Changyuan Tang, Yizhang Zhang
更新时间: 2025-01-05
摘要: The speciation and mobility of arsenic (As) in waters are largely influenced by the colloids; however, the impacts of colloids with different molecular weights (MWs) in water fractions remain largely unknown. Herein, the surface water was fractionated into three colloidal fractions and truly dissolved fraction via cross-flow ultrafiltration. Total As (As(T)) presented mainly as As(V) and existed primarily in the truly dissolved fraction. The high proportions of As(III) as 3.1%-8.0% in various size of colloids indicated a reduction condition existing in the colloids of surface water around the mine. Negative correlations between EC, TDS and As(T) and As(V) in colloids were found, indicating water properties favoured As mobilization in surface water. The aromaticity and humification of DOM reflected endogenous sources in truly dissolved fraction and large-MW colloids and exogenous sources in medium–small-MW colloids. Fourier transform infrared spectroscopy detected As-DOM and As-Fe-DOM formation in colloids, highlighting new aspects of colloids in surface water. Arsenic(T) and As(V) concentrations were positively correlated with terrestrial humic-like components and negatively correlated with microbial humic-like component in colloids, suggesting that in the closed As mine, As tended to transport from land to surface water together with terrestrial DOM, while endogenous DOM in water affected As mobilization.

109. 题目: Melamine-Assisted Synthesis of Mesoporous Biochar from Palm Kernel Shells for Enhanced Paraquat Removal from Aqueous Solutions
文章编号: N25010501
期刊: Journal of Environmental Chemical Engineering
作者: Hamza Mohamed Flafel, Mohd Rafatullah, Japareng Lalung, Riti Thapar Kapoor, Mahboob Alam, Masoom Raza Siddiqui, Mohammad Qutob
更新时间: 2025-01-05
摘要: Paraquat, a powerful herbicide, poses a global water contamination risk due to its extensive use, high solubility, and fatal consequences. Activated carbon is costly, requires a considerable volume of adsorbent, and is time-consuming to synthesise for pollutant removal. This study addresses these issues by focusing on mesoporous biochar synthesized from palm kernel shells (PKS), offering simpler synthesis method, and requiring less adsorbent for paraquat removal. Nitrogen-doping with melamine enhances the biochar's adsorption properties. Comprehensive characterization, including proximate and elemental estimation, Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) were conducted. The comparative estimation with PKS powder and KOH modified biochar was performed. Mesoporous biochar (PKS-BM) exhibited remarkable properties, including a 4.2% nitrogen composition, enhanced functional groups, a BET surface area of 794 m²/g, a total pore volume of 0.449 cm³/g, a particle size of 1400 nm, and an 81.3% paraquat removal efficiency under optimized conditions. For present study, initial paraquat concentration was 50 mg/L, an adsorbent dose of 20 mg/L, at pH of 11, a contact time of 180 minutes, and a temperature 45 °C. Adsorption kinetics were best explained by pseudo second order and Elovich models. Langmuir model indicated favourable sorption, with a maximum capacity of 454.55 mg/g. The integration of nitrogen doping with biochar synthesis not only improves contaminant removal efficiency but also aligns with the global shift toward green and scalable water treatment technologies. This study highlights the untapped potential of agro-waste-derived, functionalized biochar as an innovative and high-performance adsorbent for mitigating paraquat pollution in water systems.

110. 题目: Enhanced U(VI) separation from aqueous solution with plasma-reduced nZV Fe/Ni doped biochar: Performance and mechanism
文章编号: N25010312
期刊: Separation and Purification Technology
作者: Muhammad Shaban, Yingshan Zhu, Njud S Alharbi, Xuemei Ren, Changlun Chen
更新时间: 2025-01-03
摘要: Uranium, a radioactive element, and its contamination in the solution will give rise to severe threats to the environment and human health, which draws attention to the development of long-lasting and creative techniques for its removal. This work presented a novel and highly effective adsorbent for uranium separation: biochar (BC) supported nanoscale zero-valent iron/nickel bimetallic composite (nZV BC@Fe/Ni). Hydrogen/argon plasma (70 W for 30 min) was utilized to reduce and uniformly distribute Fe and Ni on BC. The composite’s U(VI) removal efficacy examined at four distinct mass ratios of Fe to Ni: 1:0.2, 1:0.4, 1:0.6, and 1:0.8. The nZV BC@Fe/Ni showed a remarkable removal capacity of 150.62 mg g⁻¹ and a removal rate of 93.94 % at pH 6.0 and temperature of 303 K when the mass ratio of Fe to Ni was 1:0.4, demonstrating its high level of effectiveness. In addition, the comparative study among nZV BC@Fe/Ni, BC@Fe/Ni, BC@Fe, BC@Ni, and BC illustrated that the nZV bimetallic composite comes out to be more efficient than others for U(VI) removal. The removal mechanism of U(VI) by nZV BC@Fe/Ni was elucidated. These findings not only highlight the high efficiency of nZV BC@Fe/Ni in removing U(VI) but also suggest its potential for large-scale water treatment applications due to its cost-effectiveness and scalability. The use of rice husk biochar further underscores the environmental benefits by utilizing a renewable waste product. This work provides a promising approach for tackling U(VI) contamination in aqueous solution and can be extended to other harmful metal ions, contributing to more sustainable and affordable environmental remediation strategies.

111. 题目: Visible Light-Driven Copper Vanadate/Biochar Nanocomposite for Heterogeneous Photocatalysis Degradation of Tetracycline: Performance, Mechanism, and Application of Machine Learning
文章编号: N25010311
期刊: Environmental Research
作者: Yuxuan Chen, Chuanqi Zhao, Wen Tan, Sinuo Gong, Honghui Pan, Xixiang Liu, Shiyong Huang, Qin Shi
更新时间: 2025-01-03
摘要: Water pollution caused by antibiotics is considered a major and growing issue. To address this challenge, high-performance copper vanadate-based biochar (CuVO/BC) nanocomposite photocatalysts were prepared to develop an efficient visible light-driven photocatalytic system for the remediation of tetracycline (TC) contaminated water. The effects of photocatalyst mass, solution pH, pollutant concentration, and common anions on the TC degradation were investigated in detail. Analytical techniques indicated that the CuVO exhibited a nanobelt-like structure with a uniform distribution on the wrinkled biochar surface. The XRD spectrum confirmed that the as-prepared nanomaterial was composed of Cu₃V₂O₇(OH)₂·2H₂O. Meanwhile, XPS analysis revealed that copper was present in two forms: monovalent and divalent, while vanadium remained pentavalent. The CuVO/BC exhibited excellent stability and high visible light photocatalytic activity towards TC degradation over a wide pH range. The presence of SO₄^2-, H₂PO₄⁻, CO₃²⁻, and citric acid inhibited the degradation process due to the consuming of photogenerated h⁺ and •OH, while Cl⁻ enhanced the efficiency of photocatalytic reactions due to generating chlorine oxidizing species. The CuVO/BC showed lower electron–hole recombination rate, more effective separation of photogenerated carriers, lower charge transfer resistance, and higher visible light absorption capacity comparing to pure CuVO by the addition of BC, thus improving the overall photocatalytic performance. In terms of oxidation mechanism, the EPR test and quenching experiment revealed that the contribution of the active species to the degradation of TC followed the order h⁺ > ¹O₂ > •OH > •O₂⁻. Through the application of machine learning models to analyse the influencing factors of photocatalytic processes, it was discovered that the GBDT model exhibited optimal reliability for the photocatalytic system, and the simulation results were in agreement with the experimental findings.

112. 题目: Comprehensive insights into the role of extracellular polymeric substances of Geobacter in the horizontal transfer of antibiotic resistance genes
文章编号: N25010310
期刊: Journal of Environmental Chemical Engineering
作者: Shiguang Liu, Xiaorui Wang, Zengshuai Zhang, Peng Gu, Kunlun Yang, Hengfeng Miao
更新时间: 2025-01-03
摘要: Extracellular polymeric substances (EPS) in bioelectrochemical systems play a pivotal role in the removal of antibiotics and regulation of the dissemination of antibiotic resistance genes (ARGs). However, a comprehensive analysis of the EPS secreted by electroactive bacteria is still lacking to fully understand its role in regulating ARGs transmission mechanisms. In this study, the transformation system using plasmid pBBR1MCS-3 and Geobacter to investigate the impact of EPS on transformation frequency under roxithromycin (ROX) stress. Compared with the absence of EPS, the transformation frequency of pBBR1MCS-3 in the presence of EPS was reduced by 66.8%. Results showed that EPS could decrease ROX content, thereby reducing Geobacter intracellular reactive oxygen species levels, SOS response, and cell membrane permeability. The interaction mechanism between EPS and ARGs was further elucidated through fluorescence quenching, X-ray photoelectron spectroscopy, fourier-transform infrared spectroscopy, and theoretical calculations. EPS forms a novel complex with ARGs through static quenching. Carboxyl and amine functional groups of protein in EPS could interact with ARGs via hydrogen bonding. Furthermore, PLS-PM analysis demonstrated that under ROX pressure, the secretion of EPS by Geobacter primarily reduced the horizontal genes transfer (HGT) of ARGs by alleviating oxidative stress induced by ROX. This study unveils the mechanism underlying the impact of EPS secreted by Geobacter under ROX pressure on the HGT of ARGs while highlighting its potential role in slowing down the spread of ARGs.

113. 题目: Employing microalgae cultivation on fruits and vegetable peel waste to produce biofuel, lutein, and biochar concurrently with an “Agro to Agro” algae biorefinery approach
文章编号: N25010309
期刊: Environmental Science and Pollution Research
作者: Kushi Yadav, Manasvi Vashisht, Monika Prakash Rai
更新时间: 2025-01-03
摘要:

The aim of the current investigation is to explore the novel application of pumpkin, papaya, and orange peels as growth substrates for microalgae cultivation, with the overarching goal of advancing a sustainable “Agro to Agro” biorefinery paradigm. The research evaluates the integration of waste management practices into microalgal production, optimizing growth parameters to maximize output. Optimal concentrations of 2.8 mg L⁻¹ for orange peels, 35.5 mg L⁻¹ for papaya peels, and 35.5 mg L⁻¹ for pumpkin peels were identified, alongside a light intensity of 163.7 µmol m⁻² s⁻¹ and a nitrogen concentration of 0.8 g L⁻¹. Under these conditions, Chlorella sorokiniana demonstrated peak biomass production of 3.16 g L⁻¹, lipid productivity of 1.55 g L⁻¹, and carotenoid productivity of 9.18 mg L⁻¹, additionally, yielding significant amounts of palmitic acid (47.9%) and lutein. The study further explored the conversion of residual microalgae into biochar, with optimal pyrolysis conducted at 350 °C. The as-synthesized biochar was utilized effectively as a soil amendment for cultivating Vigna radiata. The present study underscores the viability of a closed-loop biorefinery approach, demonstrating the recycling of pumpkin, papaya, and orange peels as effective substrates for microalgae cultivation and subsequent biochar conversion for potential industrial applications. The promising results of the study advocate to the feasibility of this integrated model for sustainable future.

114. 题目: Nutrient enrichment weakens the positive feedback of soil organic carbon decomposition to short-term warming in subtropical forests
文章编号: N25010308
期刊: Plant and Soil
作者: Ming-Hui Meng, Chao Liang, Jin He, Zi-Yi Shi, Fu-Sheng Chen, Fang-Chao Wang, Xue-Li Jiang, Xiang-Min Fang
更新时间: 2025-01-03
摘要:

Aims

Nitrogen (N) and phosphorus (P) deposition, along with climate warming, are key environmental factors driving soil organic carbon (SOC) dynamics in forests. The study aimed to explore the impact of N and P enrichment on soil respiration (SR) and its temperature sensitivity (Q₁₀) under short-term warming, and to reveal the underlying microbial mechanisms.

Methods

We collected soil samples from subtropical forests with 7 years of N and P additions, and conducted an incubation experiment at 15 °C, 25 °C, and 35 °C. SR and its Q₁₀, microbial carbon use efficiency (CUE), the Q₁₀ of soil extracellular enzyme activities (EEAs) and extracellular enzyme stoichiometry (EES) were evaluated.

Results

N and P additions reduced the Q₁₀ of SR within the temperature interval of 15–25 °C (moderate environment, MoE), indicating that increased nutrient availability weakens the positive feedback of SOC decomposition to warming in the MoE. The Q₁₀ of SR in the MoE was positively correlated with the Q₁₀ of β-D-cellobiohydrolase, but not with the CUE or Q₁₀ of EES, indicating that the reaction of SOC decomposition to warming depends on changes in C cycle-related enzymes rather than microbial resource availability. N addition reduced SR at 25 °C and 35 °C, and the vector length and angle of EEAs were closely related to SR, suggesting that SR depends on microbial nutrient limitation.

Conclusion

Our study highlights the importance of the Q₁₀ of soil enzymes in predicting SOC dynamics under short-term warming. Nutrient enrichment will promote SOC sequestration under climate warming in moderate environments.

115. 题目: Vertical distribution and variability of soil organic carbon and CaCO3 in deep Colluvisols modeled by hyperspectral imaging
文章编号: N25010307
期刊: Geoderma
作者: Jessica Reyes-Rojas, Julien Guigue, Daniel Žížala, Vít Penížek, Tomáš Hrdlička, Petra Vokurková, Aleš Vaněk, Tereza Zádorová
更新时间: 2025-01-03
摘要: The acceleration of soil erosion in undulating landscapes due to human activities has led to a larger area of land being affected by intensive soil redistribution. Colluvisols, sedimentary soils formed on concave slope positions, are considered to be important indicators of soil-landscape processes and soil organic carbon pools. In this study, we investigated the effectiveness of hyperspectral imaging in visible and near-infrared range to assess the detailed variability (both vertical and within each colluvial layer and in-situ soil horizon) of soil organic carbon (SOC) and CaCO3 concentrations in three deep Colluvisols developed on loess and located at different slope positions in southeast Czechia, and evaluate whether this in-detail mapped microvariability can be used as a proxy to assess the dynamics and history of colluvial sedimentation. A variety of nonlinear machine learning techniques such as cubist regression tree (Cubist), random forest (RF), support vector machine regression (SVMR) and one linear technique partial least square regression (PLSR) were compared to determine the most suitable model for the prediction of SOC and CaCO3 content in each profile. The results showed that RF provided the best performance for both SOC (R2 = 0.75) and CaCO3 (R2 = 0.76) contents. The maps depict significant differences in the vertical variability of the predicted properties in the profiles depending on the different intensity, form and period of sedimentation resulting from the slope position. The within-horizon/layer variability of SOC proves to be a suitable indicator of the character of deposition. High variability has been shown mainly in the medieval layers, where it reflects high-energy material redeposition, while low variability in the oldest and youngest parts of the profiles is probably associated with the type of deposited material and frequent pedoturbation, respectively. The within-horizon/layer variability of CaCO3, on the other hand, is independent of the dynamics of deposition. The study showed that imaging spectroscopy is a suitable tool to capture the detailed pattern of the colluvial matrix and, with appropriate sampling and processing, is applicable even in very deep soil profiles.

116. 题目: Irradiation and DOM mediate Lead Release from Polyvinyl Chloride Microplastics in Natural Surface Water
文章编号: N25010306
期刊: Journal of Hazardous Materials
作者: Mingyang Zhang, Yu Zeng, Qinglong Fu, Peixin Cui, Ning Chen, Yujun Wang, Dongmei Zhou, Guodong Fang
更新时间: 2025-01-03
摘要: Polyvinyl chloride (PVC) is a widely used plastic, but the potential risk of heavy metal additive release from PVC microplastics (MPs) has not been fully explored. This study evaluates the release of lead (Pb) from recycled PVC MPs under natural conditions. The released Pb concentration in the dark was 1079.5-1109.7, 551.4-571.6, and 374.1-433.0 μg/L in agricultural, sea, and river/lake water, respectively. In contrast, the Pb release was markedly inhibited by 34.1-59.1% under irradiation. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), fluorescence emission-excitation matrix (EEM) spectroscopy, and Mantel test revealed that the dissolved organic matter (DOM), especially lignin/carboxyl-rich acyclic component (41.8-84.8%), can complex with Pb to facilitate its release from PVC in the dark. However, the Pb released upon irradiation was first promoted and then inhibited. The promotion ascribed to the broken of MPs by reactive intermediates (RIs) including ³DOM*, ¹O₂, and ^•OH [(0.5-12.6) × 10^-13, (1.2-10.9) × 10^-13 and (0.1-8.9) × 10^-17 mol/L, respectively]. The inhibition was attributed to two reasons: the photobleaching of DOM reduced Pb dissolution complexed by DOM; the increase of oxygen-containing functional groups enhanced the Pb adsorption on the surface of MPs. In addition, the Pb released from PVC MPs significantly inhibits the growth of Nannochloropsis sp. in seawater. These findings reveal the complicated release mechanism of Pb from MPs under environmental conditions.

Environmental Implication

117. 题目: Enhanced remediation of heavy metal-contaminated soils using biochar and zeolite combinations with additives: A meta-analysis
文章编号: N25010305
期刊: Environmental Pollution
作者: Rhaila da Silva Rodrigues Viana, Jhon Kenedy Moura Chagas, Jorge Paz-Ferreiro, Cícero Célio de Figueiredo
更新时间: 2025-01-03
摘要: Soil heavy metal (HM) contamination is a major concern in agricultural lands due to its potential to enter the food chain and its adverse health effects. Remediation materials such as biochar (BC) and zeolites (ZE) have been studied for their potential to mitigate risks associated with soil HM contamination. This meta-analysis evaluates changes in the availability of Cd, Cu, Pb, and Zn following the application of BC and ZE to soil, whether applied individually, in combination (BC + ZE), or with additives (BC + ZE + A). Individually, BC reduced the availability of Cd, Cu, Pb, and Zn in soil by 24.0%, 33.0%, 31.3% and 10.1%, respectively; and ZE reduced these levels by 32.4%, 18.8%, 20.3% and 38.9%. Results indicate that, on average, BC + ZE effectively decreases the availability of Cd, Cu, Pb, and Zn in soils by 32.6%, 54.3%, 35.4%, and 18.3%, respectively. The combination with additives, BC + ZE + A, reduced the Cd and Pb availability by 54.2% and 20.9%, respectively. Most studies were undertaken with Cd, representing 59% of observations, followed by Pb, Zn, and Cu, respectively, with 29%, 8%, and 5%. The small number of studies with Pb, Zn and Cu prevented the creation of subgroups involving these three HMs. Notably, the nature of the additive influences the variation in available Cd content in remediated soils. Inorganic additives combined with BC + ZE demonstrated greater effectiveness in Cd remediation, achieving reductions of available content by 86.8%, compared to those containing clay minerals or organic compounds, with reductions of 27.4% and 15.4%, respectively. These findings enhance our understanding of how BC and ZE can be utilized in soil HM remediation and their effectiveness against different metals.

118. 题目: Estimation of soil organic carbon in arid agricultural fields based on hyperspectral satellite images
文章编号: N25010304
期刊: Geoderma
作者: Abdel Rahman S Alsaleh, Mariam Alcibahy, Fahim Abdul Gafoor, Hamed Al Hashemi, Bayan Athamneh, Ali A Al Hammadi, Lakmal Seneviratne, Maryam R Al Shehhi
更新时间: 2025-01-03
摘要: This study introduces a remote sensing approach to estimate soil organic carbon in arid agricultural fields, emphasizing sustainable land management. The United Arab Emirates (UAE) serves as the case study, representing a region where soil organic carbon dynamics have not been previously assessed. A total of 186 topsoil samples were collected and analyzed for soil organic carbon. Spectral data from field measurements, the DLR Earth Sensing Imaging Spectrometer (DESIS), and Sentinel-2 were integrated, marking the first application of this combination for soil organic carbon prediction. To address the challenges of arid environments, the study introduced specialized preprocessing techniques, including a novel vegetation index (UAEVI) for masking vegetation, principal component analysis for filling missing attributes, area normalization, and Savitzky-Golay smoothing to reduce noise and enhance spectral data. Soil organic carbon exhibited significant spectral correlations, with negative relationships observed in the wavelength ranges 401–416, 670–698, and 926–957 nm, and strong positive relationships in the ranges 519–560, 744–785, 937, and 1610 nm. A ridge regression model was developed and validated, achieving an Coefficient of Determination (R2) of 0.671, Root Mean Squared Error (RMSE) of 0.120 %, and Ratio of Performance to InterQuartile distance (RPIQ) of 2.271. The model demonstrated reliable performance in mapping soil organic carbon, achieving results comparable to studies in non-arid climates. Seasonal analysis highlighted the influence of meteorological parameters on soil organic carbon trends, and the model was successfully applied to monitor temporal changes in soil organic carbon within a sub-region from June 2022 to December 2023, revealing a slight increase in soil organic carbon over this period. This research emphasizes the effectiveness of integrating hyperspectral (DESIS) and multispectral (Sentinel-2) data with advanced preprocessing techniques for soil organic carbon estimation in arid environments. This study offers a scalable framework for more accurate and timely soil assessments, promising significant improvements in the management of arid soil ecosystems.

119. 题目: Soil carbon fractionation as a tool to monitor coastal wetland rehabilitation.
文章编号: N25010303
期刊: Journal of Environmental Management
作者: Iroshaka Gregory Cooray, Gareth Chalmers, David Chittleborough, Zeinab Ghasemzadeh
更新时间: 2025-01-03
摘要: Coastal wetland rehabilitation can provide nature-based solutions for climate change mitigation. The high carbon accumulation rate and carbon secured, potentially for several millennia, as soil organic carbon (SOC), is among the reasons. Measuring SOC storage and accrual over time are the main tools to understand rehabilitation success. However, SOC is partitioned among different organic matter fractions with varying physio-chemical properties and stabilities. In this research, we separated different organic matter fractions based on density (free light fraction: f-LF, occluded light fraction: o-LF and heavy fraction: HF) and solubility (dissolved fraction: DF) from soils taken from a wetland under rehabilitation and a pristine mangrove forest in Queensland, Australia. The f-LF and o-LF contain particulate organic carbon (POCf-LF and POCo-LF), whereas HF consists of mineral-associated organic carbon (MAOCHF). Mangroves are superior to wetlands under rehabilitation and terrestrial forests in terms of C storage in each fraction. Soils from both mangroves and wetlands under rehabilitation are dominated by MAOCHF. However, MAOCHF from mangrove soils are relatively physio-chemically stable, while wetlands under rehabilitation are leaching aged-SOC (>1000 years) from the HF to DF as dissolved organic carbon (DOCDF). Therefore, reducing the risk of mobilisation of aged-SOC can be a key to achieve rehabilitation success.

120. 题目: Diversified cropping systems with limited carbon accrual but increased nitrogen supply
文章编号: N25010302
期刊: Nature Sustainability
作者: Bo Yi, Wenjuan Huang, Matt Liebman, Matthew Woods, Marshall D McDaniel, Chaoqun Lu, Andy VanLoocke, Sotirios Archontoulis, Bryan Petersen, Siyang Jian, Hanna J Poffenbarger, Gangsheng Wang, Yiqi Luo, Steven J Hall
更新时间: 2025-01-03
摘要:

Diversified cropping systems offer a chance to mitigate environmental impacts of conventional agriculture, but effects on soil organic carbon (SOC) sequestration and nitrogen (N) dynamics remain debated. We integrated a 20-year field experiment and laboratory measurements with three stable-isotope-enabled mechanistic models to examine SOC stocks and decomposition in a conventional corn–soybean system and two more diversified systems including small grains, legumes and manure inputs, in addition to corn and soybean. Contrary to the prevalent hypothesis that diversified systems increase SOC, we found no differences in 0.3 m topsoil or 1 m profile SOC and N stocks. Diversified systems markedly increased N mineralization rates and decomposition of older SOC from previous corn inputs. Models revealed that increased C decomposition with residence times of months to years counteracted higher C inputs but increased N supply. Our findings highlight a critical trade-off between C storage and N supply in these diversified systems, demonstrating that key climate benefits may arise from decreased N fertilizer use, not SOC sequestration.