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21. 题目: Co-application of nitrification inhibitors with straw or biochar yielded varying effects on soil nitrification rate, N2O emissions, and ammonia oxidizers
文章编号: N25051702
期刊: Journal of Soils and Sediments
作者: Xiaoqian He, Jiaju He, Hongjie Shen, Zhuo Zeng, Di Zhao, Cen Cheng, Minghua Zhou, Ting Lan
更新时间: 2025-05-17
摘要:

Purpose

Nitrification inhibitors (NIs) are effective in reducing nitrification rates and nitrogen environmental losses. Yet, the combined effects of NIs with straw or biochar on soil nitrification and nitrous oxide (N₂O) production remain unclear.

Materials and methods

In this study, we performed an aerobic ¹⁵N microcosm incubation experiment to compare the effects of a biological nitrification inhibitor (methyl 3-(4-hydroxyphenyl) propionate, MHPP) and a synthetic nitrification inhibitor (3,4-dimethylpyrazole phosphate, DMPP), both in combination with straw or biochar, on gross N nitrification rates and N₂O production rates.

Results and discussion

DMPP and MHPP significantly reduced gross nitrification rates by 54.7% and 31.2%, respectively. Sole biochar application increased soil nitrification rates 1.2 times while having a negligible impact on short-term N₂O emissions. The co-application of nitrification inhibitors with biochar mitigated the stimulatory effects on nitrification. Straw inhibited nitrification slightly and stimulated N₂O emission significantly (p < 0.05), while co-application of DMPP and MHPP enhanced the inhibitory effect on nitrification by 41.4% and 62.3%, as well as reduced higher N₂O emission. Nitrification inhibitors inhibited the abundance of the amoA gene in both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB), and the communities of AOB were more sensitive to nitrification inhibitors than AOA.

Conclusion

Our findings indicated that combining nitrification inhibitors with straw or biochar can synergistically affect soil nitrification and N₂O emissions. Biochar co-applicated with DMPP showed the most significant effect on inhibiting nitrification and N₂O production, positively influencing soil inorganic N retention.

22. 题目: Transformation of dissolved organic matter during aquaculture wastewater treatment: Insights into the biological toxicity, spectral indices and molecular signatures
文章编号: N25051701
期刊: Water Research
作者: Feng Hu, Jianfeng Ye, Bingqing Wang, Wencan Zhang, Peipei Chen, Zhanzhan Yuan, Zuxin Xu
更新时间: 2025-05-17
摘要: China is a leading aquaculture producer globally and therefore, faces the critical challenge of effectively managing large volumes of aquaculture wastewater. In order to optimize treatment processes and evaluate the ecological risks from effluent discharge, it is important to understand the transformation of dissolved organic matter (DOM) and identify the key toxic components throughout the treatment process. This study focused on the ‘three ponds, two dams, one wetland’ (3P-2D-1W) treatment system, which has been widely adopted as an aquaculture wastewater treatment approach in China, investigating DOM transformation throughout the treatment process via spectroscopy, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and biotoxicity analyses. Correlation analysis indicated that biotoxicity was significantly positively correlated with dissolved organic carbon (DOC), chemical oxygen demand (COD), humification index (HIX) and modified aromaticity index (AImod_wa). Molecule-centered correlations identified aliphatic compounds and highly unsaturated phenolic compounds as the key contributors to DOM toxicity. In terms of treatment effect, the ‘three ponds, two dams’ (3P-2D) system was found to effectively reduce pollutants (59.4% DOC removal, 55.4% toxicity reduction) in aquaculture wastewater. After adding the constructed wetland module (3P-2D-1W), the treated effluent reached a DOC of 12.3 mg/L and an inhibition rate (represent for biotoxicity) of 7.16%, cleaner than the river water originally used for aquaculture (DOC 15.7 mg/L, inhibition rate 9.21%). However, the overall process showed limited selectivity for toxic compound removal. Additionally, the aeration pond exhibited redundancy and contributed to increased effluent toxicity. Analysis of potential reaction pairs revealed that the constructed wetland exhibited the highest diversity of reaction pairs (1953), with notable CHO group losses (489) and a significant increase in organic nitrogen transformation processes (±CHON, 293). This study provides novel insights into the rapid assessment indicators that can be leveraged to predict aquaculture wastewater pollution levels and offers strategic recommendations for optimizing the 3P-2D-1W treatment process.

23. 题目: Reclaiming saline-sodic land enhances soil organic carbon by altering network negative connectivity and complexity of specialists
文章编号: N25051610
期刊: Plant and Soil
作者: LiJun Zhang, Guixiang Zhou, Jiabao Zhang, Lin Chen, Donghao Ma, Congzhi Zhang
更新时间: 2025-05-16
摘要:

Background and aims

Increasing salinity and sodicity threaten soil fertility and crop yield worldwide and the accumulation of soil organic carbon (SOC) is a vital guarantee for soil improvement. However, there is still a gap in understanding how microbes influence the accumulation of SOC in saline-sodic land reclamation (converting saline-sodic land into cultivated land).

Methods

Herein, we conducted a survey of microbes in saline-sodic (solonetz) and cultivated soil collected from the Songnen Plain, and analyzed the impact of distribution patterns of niche breadth, microbial composition and multitrophic networks on SOC.

Results

Results showed saline-sodic land reclamation (reducing pH and EC) significantly increased SOC, niche breadth and microbial diversity of bacteria, fungi and protists. Microbes with significant narrow niche breadth (specialists), which associated over 85% underground connections especially negative connections, were extremely important of both network connectivity and SOC accumulation. SEM revealed that weakened negative connectivity and increased network complexity of specialists promoted the accumulation of SOC in saline-sodic land reclamation. Specialists explained 72.4% of the variance of SOC, higher than 61.3% of the whole community.

Conclusions

We demonstrated that specialists with high taxonomic diversity could facilitate SOC accumulation in saline-sodic land reclamation by strengthen multitrophic interactions. Our findings enhance the understanding of the effect of saline-sodic land reclamation on soil properties and microbial community and highlight the importance of integrating specialists into models of SOC accumulation, and these findings provide theoretical support for promoting SOC content in saline-sodic land reclamation.

24. 题目: Simultaneous adsorption of cadmium and arsenic by goethite-modified rice straw-derived biochar in water and soil: interactive ion effects and co-adsorption mechanism
文章编号: N25051609
期刊: Environmental Monitoring and Assessment
作者: Iftikhar Ali Ahmad, Hongqing Hu, Md Shoffikul Islam, Qingling Fu, Jun Zhu, Fei Miao, Muhammad Mehran, Sharjeel Haider, Zaryab Murad, Ayaz Ali
更新时间: 2025-05-16
摘要:

The coexistence of cadmium (Cd(II)) and arsenic (As(III)) has long been an environmental problem. Green and cost-effective biochar (BC) shows considerable potential for addressing environmental issues, including the concurrent elimination of cadmium (Cd(II)) and arsenic (As(III)) from water and soil after nano-sized goethite modification. However, the behavior of goethite-modified rice straw-derived biochar (GBC) during co-adsorption of Cd (II)) and As (III)) in the presence of competing ions and anoxic vs oxic environments is unclear yet. This experiment (GBC) was successfully synthesized to study co-adsorption and the effects of environmental factors on it. The adsorption kinetics and isotherms for the mixed adsorption of Cd(II) and As(III) onto GBC showed that the pseudo-2nd-order model (R² Cd(II) = 0.998, R² As(III) = 0.996) and the Langmuir model (R² Cd(II) = 0.982, R² As(III) = 0.997) were both correctly portrayed. The highest adsorption of As(III) was 87.38 mg/g, and Cd(II) was 71.07 mg/g in a single adsorption system, which is considerably more significant than the values of 68.6 and 48.38 mg/g, correspondingly, in the co-adsorption system. The competitive adsorption of Cd(II) and As(III) on GBC was primarily driven by co-precipitation and ion exchange. Its efficacy in soil systems under aerobic and anaerobic situations remained undisturbed. At the same time, the anaerobic environment favors Cd adsorption, and the aerobic environment favors more As remediation in an aqueous system. The interactive ions Ca²⁺ and Mg²⁺ significantly enhanced the adsorption of As(III). On the other hand, phosphate and humic acid significantly promote Cd(II) adsorption. In summary, the different environmental conditions revealed by this study help a deeper understanding of the behaviors of As and Cd by GBC.

25. 题目: Biochar impact on soil properties and soil solution nutrient concentrations under cotton production.
文章编号: N25051608
期刊: Journal of Environmental Management
作者: Ramandeep Kumar Sharma, Gurbir Singh, Amrinder Jakhar, Jagmandeep Dhillon, Saseendran S Anapalli, Kelly A Nelson, Gurpreet Kaur
更新时间: 2025-05-16
摘要: Intensive tillage and unsustainable agricultural practices adversely impact soil health and the long-term sustainability of crop production in humid subtropics. Biochar, a soil amendment, can be used to improve soil properties and agricultural productivity. A field experiment evaluated the impact of biochar application rates (B) (0, 10, 20, and 40 Mg ha-1) on soil properties and soil solution chemistry under rainfed cotton (Gossypium hirsutum L.) production systems in the Lower Mississippi Delta from 2020 to 2022. An application of 40 Mg ha-1 of biochar significantly reduced bulk density and increased water content in 0-15 cm compared to other rates and depths. Biochar increased aggregate stability compared to the control in the topsoil layer for aggregate fractions of size 0.5-1 mm and 1-2 mm in 2021. Biochar application at 20 and 40 Mg ha-1 reduced NO3-N concentration in soil by 63 % and 53 %, respectively, compared to the control at a 0-15 cm depth in 2021. Biochar applications reduced soil solution NO3--N losses 49 %-87 % and 42 %-102 % during the fallow period compared to the control at a 46 and 81 cm depth, respectively. Biochar also reduced the soil solution PO43--P concentration 14 %-39 % compared to the control in the fallow period. Biochar improved soil properties while reducing nutrient losses in the soil solution and has the potential to be an alternative soil amendment strategy for sustainable cotton production.

26. 题目: Temporal thresholds and depth-specific mechanisms of soil organic carbon stabilization during 65 years of revegetation in the Tengger Desert
文章编号: N25051607
期刊: Journal of Environmental Management
作者: Ting Zhang, Bin Niu, Yongli Wang, Zhifu Wei, Gen Wang, Xueyun Ma, Xinrong Li
更新时间: 2025-05-16
摘要: Revegetation is a widely adopted strategy to combat desertification and enhance soil organic carbon (SOC) storage in dryland ecosystems. However, the depth-dependent stabilization mechanisms of SOC and their temporal dynamics during long-term revegetation remain poorly understood, limiting accurate predictions of carbon sequestration potential. Here, we addressed this knowledge gap by applying sequential chemical extractions to quantify six operationally defined organic carbon (OC) fractions, reflecting different stabilization pathways, across three soil horizons over a 65-year revegetation chronosequence in the Tengger Desert. Our results show that the composition of SOC varies markedly with soil depth and revegetation age. In the organic horizon (Oh), SOC is primarily composed of residual OC (32 %–53 %) and metal-OC complexes (25 %–32 %). In the topsoil, the contribution of metal-bound OC (from 39 % to 22 %), carbonate-bound OC (from 26 % to 13 %), and iron oxide-bound OC (from 20 % to 6 %) decreases over time, while residual OC increases from 16 % to 54 %. In the subsoil, SOC consists mainly of carbonate-bound OC (27 %–58 %) and metal–OC complexes (21 %–34 %). We also identified clear temporal thresholds for accelerated SOC accumulation: after 34 years in the Oh and topsoil horizon, driven primarily by the increase in the residual OC, and after 57 years in the subsoil, due to higher contents of metal–OC complexes and residual OC. These thresholds are controlled by distinct factors across horizons—plants in the Oh horizon, biocrusts in the topsoil, and edaphic conditions in the subsoil. Our findings underscore the horizon-specific responses of SOC fractions to revegetation over time, offering mechanistic insights into SOC stabilization in drylands. This research provides a scientific basis for depth-targeted carbon management and emphasizes the importance of long-term revegetation in enhancing SOC storage in dryland ecosystems.

27. 题目: Carbon in river floodplains
文章编号: N25051606
期刊: Nature Climate Change
作者: Bronwyn Wake
更新时间: 2025-05-16
摘要:

Rivers play an important role in the transport and alteration of sediment and organic carbon. Yet, the role of floodplains in terrestrial carbon storage is poorly quantified as rivers vary in their erosion rates, transport and deposition of sediment, influenced by meanders, width and depth, among others.

To better understand what controls the timescales for carbon and sediment storage in river floodplains, Emily Geyman of the California Institute of Technology and co-authors used simulations, along with geomorphic mapping and dating techniques, applied to three Alaskan field sites with diverse characteristics. They show that the storage timescales can be predicted from the channel migration rate, channel width and the floodplain width.

28. 题目: Evaluating the potential of digestate-loaded biochar in improving soil biological health and plant nutrition with less greenhouse gas emissions
文章编号: N25051605
期刊: Environmental Pollution
作者: Yunyun Zheng, Lynette Abbott, Nanthi Bolan, Pankaj K Singh, Sasha N Jenkins, Bede S Mickan
更新时间: 2025-05-16
摘要: Digestate has a great potential as a carbon (C) and nitrogen (N) soil amendment. Loading digestate onto biochar can produce a C- and N- enriched biochar fertilizer (i.e., digestate-loaded biochar, DLB), and help to solve digestate-specific issues. This study aims to evaluate the potential of DLB at optimal application rates in keeping plant (annual ryegrass) nutrition level while mitigating greenhouse gas emissions and improving soil biological health compared to chemical fertilizers under liming or not. Soil biological health index was assessed through quantitative PCR and amplicon sequencing. The results showed that increasing DLB addition to 150 kg N ha^-1 resulted in a similar N uptake of ryegrass to that under urea despite lower mineral N provided by DLB. This application rate decreased greenhouse gas emissions relative to urea, through decreasing CO₂ emission despite increased CH₄ emission. Compared to urea, this DLB rate did not change N₂O emission, corresponding to the specifically increased abundance of nirK gene (1.3-fold) (and enriched denitrifier Dokdonella) for N₂O production and nosZ clade I and II genes (87%) for N₂O consumption. The DLB at 150 kg N ha^-1 enhanced soil biological health index by 1.4-fold relative to urea through increasing microbial abundances particularly fungi, enriching beneficial microbes (plant-growth-promoting bacteria, mycorrhiza and dark-septate-endophyte), and increasing fungal diversity; this effect was less pronounced under liming. This study concludes that DLB can serve as an organic-mineral fertilizer in maintaining plant nutrition while decreasing greenhouse gas emissions and enhancing soil biological health, offering a sustainable approach to managing organic waste.

29. 题目: Dissolved black carbon in full-scale drinking water treatment plants: Occurrence and contribution to disinfection byproducts formation and cytotoxicity
文章编号: N25051604
期刊: Journal of Hazardous Materials
作者: Haoran Chen, Jianwei Li, Chuze Chen, Xiating Zhao, Zongcheng Yao, Yuting Wang, Zhigang Li, Qiming Xian
更新时间: 2025-05-16
摘要: Dissolved black carbon (DBC) is a crucial precursor to disinfection byproducts (DBPs) in the drinking water disinfection process. However, the understanding of the presence and transformation of DBC within drinking water treatment plants (DWTPs) is still limited. This article systematically examined the presence and transport of DBC, in combination with the contribution to disinfection byproducts formation and cytotoxicity along the full-scale DWTPs. The results indicated that DBC concentrations varied from 70.0–199.4 μg/L in source water, 28.7–122.7 μg/L in sedimentation, 22.5–68.5 μg/L in carbon filter, 27.8–116.7 μg/L in sand filter and 7.2–23.0 μg/L in finished water. Sedimentation and disinfection processes resulted in higher DBC removal rates of 57% and 71% on average, respectively. DBC components with high aromaticity were predominantly removed during sedimentation, while DBC with low aromaticity was more likely to be removed during chlorination. DBC concentration had a significantly positive correlation with UV₂₅₄ absorbance throughout the entire treatment process. Additionally, although DBC in the source water constituted only 1–10% of the dissolved organic matter, DBC was estimated to contribute to 1–25% of the DBP formation and 1–20% of the cytotoxicity in the finished water. Hence, it is crucial to consider the possible risk of DBPs generated in the disinfection of DBC along the full-scale DWTPs.

30. 题目: Global Change Modulates Microbial Carbon Use Efficiency: Mechanisms and Impacts on Soil Organic Carbon Dynamics
文章编号: N25051603
期刊: Global Change Biology
作者: Jingwei Shi, Lei Deng, Jianzhao Wu, Yuanyuan Huang, Yajing Dong, Josep Peñuelas, Yang Liao, Lin Yang, Xingyun Huang, Hailong Zhang, Jiwei Li, Zhouping Shangguan, Yakov Kuzyakov
更新时间: 2025-05-16
摘要: Microbial carbon use efficiency (CUE) is a key parameter of initial microbial utilization of organic matter in soil. The responses of CUE to global change factors (GCFs) remain unclear due to their multiple effects and interactions. Here, this study generalized 385 observations obtained using various methods, including ¹³C-/¹⁴C-labeled substrates, ¹⁸O-labeled water, stoichiometric modeling, and others. The effects of climate change (drought, precipitation, warming), fertilization (nitrogen addition, phosphorus addition, potassium addition, and nitrogen fertilization combined with phosphorus and potassium), land use conversion, and natural restoration, were evaluated along with their 16 associated GCFs on CUE. CUE was insensitive to climate change factors and most fertilization practices, maintaining a mean value of 0.36 under global change scenarios. Farmland conversion to forest and vegetation restoration decreased CUE by 11% and 17%, respectively. Grassland restoration increased CUE by 41%, indicating that grasslands have high potential for soil carbon accrual. Nitrogen fertilization combined with phosphorus and potassium increased CUE by 18% because the combined application of nutrients allows plants to produce organic matter sources with high-quality and decreases nutrient limitations for microorganisms. Increase in soil pH induced by GCFs leads to higher CUE. The CUE was decoupled from soil organic carbon content under several global change scenarios (e.g., warming, fertilization), suggesting that this relationship is not universally consistent across GCFs. This study provides a new perspective on the responses of CUE to GCFs and deepens our understanding of the global change effects on microbial physiology with consequences for soil carbon cycling.

31. 题目: Parent material geochemistry – and not plant input – as the primary element shaping soil organic carbon stocks in European alpine grasslands
文章编号: N25051602
期刊: Biogeosciences
作者: Annina Maier, Maria E Macfarlane, Marco Griepentrog, Sebastian Doetterl
更新时间: 2025-05-16
摘要: . Soils represent the largest terrestrial carbon (C) reservoir on Earth. Within terrestrial ecosystems, soil geochemistry can be a strong driver of plant-soil-carbon dynamics, especially in young, less weathered soils. Here, we investigate the impact of potential plant biomass input, soil fertility parameters, and soil organic carbon (SOC) stabilization mechanisms on the distribution of SOC in European alpine grasslands across gradients of geochemically distinct parent materials. We demonstrate that SOC stock accrual in geochemically young, developing alpine soils is dependent on soil mineralogy as a result of parent material weathering, and is not strongly linked to plant biomass input. We show potential differences in the importance of SOC stabilization mechanisms, with universally large relative contributions (≥ 50 %) of the microaggregate soil fraction to bulk SOC. We further show that concentrations of Fe, Al and Mn pedogenic oxides coincide with SOC stock magnitude across an alpine soil geochemical gradient, where SOC stocks range between 8.1–23.2 kg C m⁻². Our results highlight that soil fertility, which governs plant C inputs, and soil mineralogical characteristics, which control C stabilization, play equally crucial roles in predicting SOC contents in alpine soils at an early development stage, corroborated by soil fraction modern (F14C) values ranging from 0.77–1.06.

32. 题目: Heterotrophy of particulate organic matter subsidies contributes to divergent bleaching responses in tropical Scleractinian corals
文章编号: N25051601
期刊: Limnology and Oceanography
作者: Connor R Love, Kelly E Speare, Michael D Fox, Veronica Z Radice, Kelton W McMahon, Gretchen E Hofmann, David L Valentine, Marie E Strader
更新时间: 2025-05-16
摘要: Heterotrophic feeding on plankton and particulate organic matter (POM) by tropical Scleractinian corals is known to aid in the resistance and recovery from thermally induced bleaching. However, the relative importance of heterotrophy in promoting bleaching resistance and recovery is likely to vary based on ecological context and the severity of heat stress. In 2019, the Pacific Island of Mo'orea experienced mass coral mortality during a widespread marine heatwave. Many Acropora hyacinthus colonies on the shallow reef slope (5 m) were resistant to bleaching, while colonies on the deeper fore reef (14 m) often bleached and subsequently recovered, despite similar thermal stress. The role of heterotrophy in this divergent bleaching response was investigated using fatty acid (FA), isotopic, and elemental biomarkers. Multiple complementary lines of evidence, including feeding proxies, isotopic niche overlap, and putative POM FA biomarkers, indicated that bleaching resistant colonies were likely consuming more POM than their bleached and recovered counterparts. Additionally, although visually recovered, host energetics in recovered colonies remained compromised and exhibited proportionally less monounsaturated and polyunsaturated FAs and less relative nitrogen than resistant colonies. We show that corals that rely more on heterotrophic nutrient acquisition can better resist thermally induced bleaching. Our results also revealed the long‐term energetic costs of bleaching even after visual recovery. Ultimately, these results underscore the vital role of coral nutrition in shaping coral bleaching response and recovery.

33. 题目: Enhanced peroxymonosulfate activation by ball-milling-assisted nitrogen-doped animal-derived biochar for sulfamethoxazole degradation: Unveiling multiple non-radical mechanisms
文章编号: N25051510
期刊: Separation and Purification Technology
作者: Weicheng Xu, Haishan Guan, Zhang Liu, Xueding Jiang, Xiaolian Wu, Bo Ruan, Yuhai Sun, Xiaofei Li, Hailong Wang, King Lun Yeung
更新时间: 2025-05-15
摘要: Animal-derived biochar, rich in aromatic hydrocarbons and oxygenated functional groups, is a promising material for peroxymonosulfate (PMS) activation. In this study, nitrogen-doped biochar composite (BNAPBC) was successfully synthesized through ball milling acid-washed pig carcass biochar and ammonia solution, and applied for PMS activation in sulfamethoxazole (SMX) degradation. BNAPBC achieved 95.7 % SMX removal in 40 min, with 36-fold enhanced kinetics compared to pristine pig biochar (PBC). The BNAPBC/PMS system effectively removed over 93 % of SMX across a broad initial pH range (2.35–9) and demonstrated strong tolerance to inorganic ions and diverse water quality. Quenching tests, electron paramagnetic resonance (EPR), PMS decomposition experiments, and electrochemical tests confirmed SMX degradation primarily occurred through non-radical pathways, mainly driven by ¹O₂ and surface-bound radicals, with electron transfer-mediated pathways playing a secondary role. X-ray photoelectron spectroscopy (XPS) identified pyridinic N, C=O, and C=C groups as active sites, density functional theory (DFT) calculations revealed a dual active site for BNAPBC, PMS activation on pyrrolic N and O-O bond elongation at pyridinic N, promoting SO₄^•−/·OH generation. Electrostatic potential (ESP) and intermediate identification further proposed SMX degradation pathways. This study highlights the potential of animal-derived biochar in addressing environmental pollutants and supports the sustainable valorization of animal waste.

34. 题目: A circular economy approach for harnessing inorganic and organic carbons coupled with waste remediation using Chlorella minutissima for sustainable biodiesel production
文章编号: N25051509
期刊: Journal of Environmental Chemical Engineering
作者: Sagar Devadiga, Sudatta Maity, Nirupama Mallick
更新时间: 2025-05-15
摘要: By utilizing carbon dioxide (CO₂) and carbon-rich agro-wastes, which are major contributors to global warming and pollution, the current study aims to harness renewable energy while facilitating waste remediation through cultivation of a green microalga Chlorella minutissima. This research investigates the individual and synergistic effects of CO₂ and organic solid wastes, including cow dung (CD), poultry litter (PL), sugar molasses (SM), and sweet lime peels (SL), on microalgal biomass and lipid productivity. Analysis showed that a CO₂ concentration of 12% at airflow of 0.3 vvm significantly enhanced biomass and lipid concentrations, while PL emerging as the most effective waste source. Combining 12% CO₂ at 0.3 vvm + 4 g L^-1 PL with N 11 medium (OMix condition) resulted in the maximum biomass concentration of 5.4 ± 0.2 g L^-1 and a lipid concentration of 1821 ± 35 mg L^-1, highlighting significant improvements in microalgal productivity. C. minutissima also exhibited a high CO₂ assimilation rate of 0.85 ± 0.05 g L^-1 d^-1 and a total nutrient removal efficiency of ~94%, demonstrating its potential in carbon sequestration and waste remediation. Additionally, poultry litter exhibited a good buffering capacity under CO₂ supplementation. Lipids extracted under OMix condition were converted into biodiesel with ~88% efficiency, yielding ~93% fatty acid methyl ester (FAMEs), predominantly composed of saturated and monounsaturated fats. The produced biodiesel met both national and international standards, demonstrating its viability as a sustainable biofuel. This study thus highlights the triple benefits of carbon capture, waste remediation and biodiesel production by C. minutissima under a circular economy frame-work.

35. 题目: Regulating factors and spatiotemporal patterns of terrestrial dissolved organic carbon adsorption in a high-turbidity estuary
文章编号: N25051508
期刊: Water Research
作者: Zhi Chen, Ricardo Torres, Jialing Yao, Ding He, Daidu Fan, Daniel Conley, Andrew Manning, Jianzhong Ge
更新时间: 2025-05-15
摘要: The adsorption of terrestrial dissolved organic carbon (tDOC) onto surfaces of suspended sediment plays a fundamental role in regulating carbon fluxes across the river-estuary-ocean continuum. It is an important process that modulates carbon transport, transformation, and long-term carbon storage, influencing regional and global carbon budgets. However, the role of suspended sediment is frequently neglected in related coastal and estuarine studies due to the complex interplay of physical and biogeochemical processes. To elucidate the relationship between suspended sediment and tDOC and quantify the adsorption process, this study developed a tDOC-adsorption-floc-population model that integrates floc behavior with tDOC adsorption processes. Taking the Changjiang Estuary as an example, the model quantified tDOC removal through adsorption and examined the key mechanisms governing this process. Results indicate that approximately 12.8 $\pm$ 1% of DOC is removed via adsorption when passing through the turbidity maximum zone (TMZ). The dominant mechanism of tDOC adsorption is governed by floc size, with Brownian motion and differential sedimentation alternating as the primary mechanism, whereas fluid shear exerts a relatively minor influence. The adsorption process is spatially aligned with the TMZ, but its influence, driven by the hydrodynamics, can extend into adjacent areas. These findings highlight the need for incorporating suspended sediment dynamics into regional and global carbon cycle models to enhance predictions of carbon transport and transformation in estuarine and coastal systems.

36. 题目: Food waste biogas residue-derived composite biochar for effective Cu2+ removal by capacitive deionization
文章编号: N25051507
期刊: Journal of Environmental Chemical Engineering
作者: Zhenyi Zhao, Lili Yan, Guanghui Li, Pinhua Rao, Benjiao Huo, Tiantian Li, Yuliang Li, Zhaoziyue Zhang, Yiran Sun, Jiao Xue
更新时间: 2025-05-15
摘要: Capacitor deionization (CDI) technology has potential applications in heavy metal removal with low operating cost, environmental friendliness, and comprehensive benefits for water remediation. In this work, using food waste biogas residue as the carbon source, food waste biogas residue composite biochar with rich pore structure was prepared by adding tobacco stalk and KOH activation as the CDI electrode material, and Cu²⁺ was taken as target pollutant for heavy metal removal studies. The pore volume of food waste biogas residue composite biochar with activation temperature at 600 ℃ was 2 times larger than that of food waste biogas residue and tobacco stalk biochar. The influence of temperature on structure, composition, electrochemical performance of biochar was further systematically investigated. Food waste biogas residue composite biochar with activation temperature at 800 ℃ (ABTC800) exhibited much larger specific surface area (2044.58 m²/g), abundant porous structure (1.29 cm³/g), and higher specific capacitance. The removal capacity of ABTC800 electrode can be up to 171.26 mg/g at 3 h in 50 mg/L Cu²⁺ solution at a voltage of 0.8 V. Weak acidity is more favorable for Cu²⁺ adsorption. ABTC800 had an excellent adsorption capacity towards Cu²⁺. In addition, characterizations revealed that Cu²⁺ removal mainly relied on electrostatic adsorption, surface complexation, precipitation, and reduction during the whole process. This study proposed a promising strategy of biogas residue reuse for heavy metal removal.

37. 题目: Enhanced retention of arsenite and arsenate through heterogeneous interactions between Fe(III) (Hydr)Oxides and black carbon: a multi-mechanistic study
文章编号: N25051506
期刊: Chemical Engineering Journal
作者: Bingyu Li, Miaomiao Jing, Jingru Li, Zhuoqing Li, Haojie Cui, Yimin Zhou, Dongning Wei, Saihua Liu, Yunhe Xie, Xionghui Ji, Ming Lei
更新时间: 2025-05-15
摘要: Amorphous Fe(III) (hydr)oxides ubiquitously interact with organic matter, forming organic–inorganic assemblages in natural environments. Yet, how their hetero-aggregation with pyrogenic organic matter influences coexisting pollutants remains unclear. Herein, we simulated two associations of rice straw-derived black carbon (RBC) with Fe(III) oxide, by employing different formation scenarios (sorption and coprecipitation) across various Fe/C ratios. Batch experiments and microscopic characterization techniques (e.g. XRD, XPS, FTIR, BET) were used to evaluate the effects of hetero-aggregation between RBC and Fe(III) oxides on the fate of the co-presence of As(III) and As(V). We showed that iron minerals and RBC mainly through –COOH and Si-O bonds formed different Fe/C associations, and RBC greatly modified the surface properties of iron minerals (e.g. zeta potential, pore structure). Batch experiments demonstrated that RBC significantly improved the retention of As(III) and As(V) on iron minerals, with a pronounced effect on As(V). Our multi-mechanistic study, utilizing non-local density functional theory, radical quenching, and electrostatic interactions, demonstrated that the hetero-aggregation of RBC/Fe(III) oxides resulted in the formation of more characteristic pores across various mineral systems, significantly enhancing the pore diffusion of As(III) and As(V) within the bulk mineral matrix. We identified distinct electrostatic interactions between As(III)/As(V) and various mineral end-members, with As(V) promoting the aggregation of iron oxides and decreasing pore width, whereas As(III) exhibited minimal impact on the pore structures of iron oxides. Interestingly, RBC enhanced the resistibility of the pore structure against negative potential, thereby facilitating the extensive diffusion of As(III) and As(V). Furthermore, we identified that RBC-mediated radical reaction also contributed to the immobilization of As(III). Our findings help better understand how arsenic behaves under black carbon-rich geological settings where iron-carbon coupled reactions prevail.

38. 题目: A nine-year study: continuous application of biochar achieves efficient potassium supply by modifying soil clay mineral composition and its potassium adsorption sites
文章编号: N25051505
期刊: Journal of Soils and Sediments
作者: Hangming Guo, Zhengchao Wu, Jiaxin Li, Zonglin Lu, Shuxiao Luan, Shixin Hu, Xingyu Liu, Na Li, Xiaori Han
更新时间: 2025-05-15
摘要:

Purpose

Biochar’s effectiveness in enhancing soil potassium availability has been well established in short-term pot experiments, but its long-term impact remains unclear. This study evaluates the effects of continuous biochar application on potassium supply by analyzing clay mineral composition and potassium adsorption sites in field conditions.

Methods

A nine-year field experiment was conducted to assess the effects of varying biochar application rates (1500, 3000, and 6000 kg ha⁻¹), applied alone or in combination with chemical fertilizers, on potassium forms, clay mineral composition, and potassium adsorption sites in brown soil.

Results

The results demonstrated that biochar application significantly increased available and slowly available potassium by 17.21 to 51.98% and 31.73 to 54.01%, respectively, with these positive effects becoming even more pronounced when biochar was combined with chemical fertilizers. Biochar also altered soil clay minerals (particles < 2 μm in size) composition, increasing illite and transforming kaolinite, vermiculite, and chlorite, enhancing potassium release and storage. Potassium content at p-sites, e-sites, and i-sites within clay minerals increased, particularly when combined with fertilizers. Additionally, biochar improved soil properties such as alkaline-hydrolyzable nitrogen, available phosphorus, organic matter, and cation exchange capacity, thereby indirectly enhancing the retention and supply of potassium in the soil.

Conclusion

Biochar, particularly with fertilizers, significantly enhances soil potassium availability and ensures its long-term supply. This study highlights biochar as a promising strategy for potassium management in agricultural soils, warranting further research across diverse soils and conditions.

39. 题目: Enhancing Carboxyl Groups in Humic Acid with Selective Catalyst to Mitigate Active N Loss through Nitrification and Denitrification Inhibition in Low-Fertility Calcareous Fluvo-Aquic Soil
文章编号: N25051504
期刊: ACS Sustainable Chemistry & Engineering
作者: Yingqiang Zhang, Shuiqin Zhang, Meng Xu, Jianyuan Jing, Jiukai Xu, Yanting Li, Bingqiang Zhao, Liang Yuan
更新时间: 2025-05-15
摘要: Nitrogen (N) derived from urea is easily lost through transformation in agricultural production, raising sustainability problems for resource and environmental development. Humic acid (HA) presents considerable potential for mitigating active N loss owing to its carboxyl group. However, there is a gap in targeted enrichment of carboxyl groups in HA to conquer its inherent low content. In this study, we developed oxygen vacancy-rich CuO–Fe₃O₄@BC as a novel catalyst containing Cu(I)/Cu(II) and Fe(II)/Fe(III) redox cycling. The catalyst successfully enriched the carboxyl groups of HA by 96.13%, assisted by H₂O₂. The enrichment was attributed to the targeted breakage of the C═C bonds in condensed aromatics with ≥4-benzene rings by CuO–Fe₃O₄@BC. We then prepared raw HA-enhanced urea (RHAU) and carboxyl-enriched HA-enhanced urea (CHAU) using raw HA and carboxyl-enriched HA, respectively. Subsequently, we conducted a series of incubation experiments to determine the effects of CHAU on active N loss. The results indicated that compared to RHAU, CHAU delayed the urea hydrolysis by inhibiting the urease activity and decreased the total accumulation of NH₃ volatilization by 15.07% by altering the abundance and community structure of ammonia-oxidizing bacteria. It also decreased the total accumulation of N₂O emissions by 6.69% by reducing the abundance of nirK genes and altering the community structure of nirS genes. Thus, this study demonstrated an approach for the targeted enrichment of the carboxyl group of HA to mitigate active N loss and guide the development of high-efficiency N fertilizers in agriculture and environmental sustainability.

40. 题目: Minerals, Microbes and Melanin Drive Differential Incorporation of Fungal Necromass Carbon and Nitrogen into Mineral-Associated Organic Matter
文章编号: N25051503
期刊: Soil Biology and Biochemistry
作者: Katilyn V Beidler, Elizabeth Huenupi, Lang C DeLancey, François Maillard, Bowen Zhang, Per Persson, Peter G Kennedy, Richard Phillips
更新时间: 2025-05-15
摘要: Despite the importance of mineral-associated organic matter (MAOM) in long-term soil carbon (C) and nitrogen (N) persistence, and the significant contribution of fungal necromass to this pool, the factors controlling the formation of fungal-derived MAOM remain unclear. This study investigated how fungal necromass chemistry, specifically melanin, interacts with soil mineral properties and microbial communities to influence MAOM formation and persistence. We cultured the fungus Hyaloscypha bicolor to produce ¹³C- and ¹⁵N-labeled necromass with varying melanin content (high or low) and incubated it in both live and autoclaved soils collected from six Indiana forests that differed in their clay and iron oxide (FeOx) content. After 38 days, we found that seven times more fungal-derived N was incorporated into MAOM than fungal-derived C, with fungal N comprising 20% of the MAOM-N pool. Low melanin necromass formed more MAOM-C than high melanin necromass, although site-level differences in overall MAOM formation were substantial. Soil clay and FeOx content were strong predictors of MAOM formation, explaining ∼60% and ∼68% of the variation in MAOM-C and MAOM-N, respectively. However, microbial communities also significantly influenced MAOM formation, with MAOM-C formation enhanced and MAOM-N formation reduced in autoclaved soils. Furthermore, the relative abundance of fungal saprotrophs was negatively correlated, and bacterial richness was positively correlated with MAOM formation, and these relationships were influenced by necromass melanin content. Collectively, this study reveals that microbial communities and soil properties interactively mediate the incorporation of fungal necromass C and N into MAOM, with microbes differentially influencing C and N incorporation, and these processes being further modulated by necromass melanization.