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241. 题目: Promoting the recovery of soil health in As and Sb-polluted soils: new evidence from the biochar-compost option
文章编号: N24122108
期刊: Environmental Science and Pollution Research
作者: Amina Boukhatem, Oualida Rached, Alima Bentellis, Sotirios Vasileiadis, Paola Castaldi, Giovanni Garau, Stefania Diquattro
更新时间: 2024-12-21
摘要:

The role of compost and biochar in the recovery of As and Sb-polluted soils is poorly investigated, as well as the influence of their application rates on soil health and quality. In this study, we therefore investigated the effectiveness over time (2, 4, and 6 months, M) of a municipal solid waste compost (MSWC) and a biochar (BC), applied at 10 and 30% rates, and of selected mixtures (MIX; applied at 10 and 30% total rates, 1:1 ratio of MSWC and BC), on labile As and Sb in a polluted soil from an abandoned Sb mine (Djebel Hamimat, Algeria). At the same timepoints, the amendment impact on soil chemistry was also monitored, while the activity and diversity of the resident microbial communities were investigated at 6 M. After 6 months, MSWC, BC, and MIX applied at the higher rate significantly increased soil pH (from 7.5 up to 8.2), while MSWC and MIX increased soil EC to worrying values. The soil dissolved organic carbon content was also greatly increased by MSWC and MIX at the higher rates (up to 50-fold), while BC showed a negligible impact. All the amendments reduced the concentration of labile Sb in soil, with BC 10% being the most effective treatment (i.e., reducing labile Sb from ~ 60 to 20 mg kg⁻¹ soil). On the contrary, only BC and MIX applied at 10% significantly reduced labile As (e.g., from ~ 12 to 4 mg kg⁻¹ soil in the case of BC). MSWC and MIX at both rates increased up to 2000-fold soil dehydrogenase activity, while BC showed a null impact. The Biolog community level physiological profile and sequencing of the partial 16S rRNA gene showed a reduction of catabolic activity and α-diversity and a change of the community composition of bacterial populations in treated soils. Overall, MIX treatment, especially at 10%, was the most promising option for the chemical and biological recovery of As and Sb-polluted soils.

242. 题目: No saturation of soil carbon under long-term extreme manure additions
文章编号: N24122107
期刊: Plant and Soil
作者: Henrike Heinemann, Axel Don, Christopher Poeplau, Ines Merbach, Thorsten Reinsch, Gerhard Welp, Cora Vos
更新时间: 2024-12-21
摘要:

Background and aims

According to the carbon (C) saturation concept, the capacity of soils to accumulate stabilized organic C is limited by the number of binding sites on mineral surfaces. The concept and its application are highly debated. Therefore, we aimed at testing this theory using field experimental data.

Methods

Soils were sampled from four long-term field experiments with different amounts of organic fertilisation going up to extreme high C inputs (20 Mg C ha⁻¹ yr⁻¹) five times higher than in common agricultural practice. Soils were fractionated by particle size to obtain sand-sized, coarse silt and fine silt plus clay fractions.

Results

We found a linear relation between C input and soil organic carbon stocks (SOC) even with vast amounts of organic C inputs to the soil at three experimental sites. Across all experiments, C stocks in the sand-sized fraction increased on average by 146%, whereas C stocks in the fine silt plus clay fraction (< 20 µm) increased by just 17% without distinct saturation behaviour. The C sequestration efficiency (amount of C retained as SOC per amount of C input) tended to increase with initial SOC content which is not in line with the saturation theory.

Conclusion

The experiments were subject to C inputs via organic fertilisation that would and should rarely be reached in agricultural practice due to negative side effects. Even under these artificial conditions experiments did not show a distinct saturation behaviour.

Initial SOC stocks or SOC in the mineral-associated fraction did not appear to limit the potential of soils to sequester additional SOC. It can be concluded that C sequestration is mainly limited by the availability of C inputs from biomass.

243. 题目: Ammonia nitrogen affects bacterial virulence and conditional pathogenic bacterial growth by regulating biofilm microbial metabolism and EPS secretion in laboratory scale distribution systems
文章编号: N24122106
期刊: Science of the Total Environment
作者: Huifang Sun, Xiurong Ju, Haibo Wang, Xu Ma, Baoyou Shi
更新时间: 2024-12-21
摘要: The control of conditional pathogenic bacteria and inhibition of their virulence factors (VFs) in drinking water distribution systems (DWDSs) is vital for drinking water safety. This study adopted two groups of DWDSs to investigate how ammonia nitrogen affects bacterial VFs and conditional pathogenic bacterial growth in biofilms. Our results indicated that Acidimicrobium (95,916.62 ± 119.24 TPM), Limnohabitans (30,338.81 ± 139.14 TPM), and Sediminibacterium (10,658.01 ± 48.94 TPM) were predominant in the biofilm bacterial community of DWDSs with NH3-N addition. Under these conditions, the abundances of various bacterial metabolites, such as L-glutamate (1.45-fold), 2-oxoglutarate (1.24-fold), pyruvate (2.10-fold), and adenosine monophosphate (AMP, 5.29-fold), were significantly upregulated, which suggested the upregulation of amino acid, carbohydrate, nucleotide, lipid, pyrimidine and purine metabolism. These metabolic pathways accelerated extracellular polymeric substance (EPS) secretion. The protein concentration in EPS also increased to 187.59 ± 0.58 μg/cm2. The increased EPS secretion promoted the amide I CO group of the EPS protein to interact with the surface of the DWDSs, thus enhancing the ability of bacteria (especially conditional pathogenic bacteria) to adhere to the pipe surface to form biofilms. Due to EPS protection, the abundance of the adherence subtype of VFs and the plate counts of Pseudomonas aeruginosa increased to 5912.8 ± 21.89 TPM and 655.78 ± 27.10 CFU/cm2, respectively. Therefore, NH3-N in DWDSs increased bacterial VFs levels and promoted the growth of some conditional pathogenic bacteria by regulating biofilm microbial metabolic pathways and EPS secretion, ultimately impacting the interaction between EPS and the pipe surface.

244. 题目: The Impact of Different Functional Groups of Biochar on Mercury Adsorption Investigated by Density Functional Theory
文章编号: N24122105
期刊: Journal of Cleaner Production
作者: Kexin Chen, Jinying Li, Yuxuan Zhang, Bin Chen
更新时间: 2024-12-21
摘要: Investigating the impact of biochar functional groups on mercury adsorption performance can provide theoretical guidance for the search and design of high-performance mercury adsorbents. However, due to the highly heterogeneous nature, structural diversity, and surface complexity of biochar, current experimental techniques struggle to elucidate the detailed effects and mechanisms of each functional group. This study employs Density Functional Theory and wavefunction analysis methods to construct eight molecular models with different single and dual functional groups. We calculated and analyzed the adsorption energy, C-Hg bond length, charge transfer, surface electrostatic potential, and electron localization function for each model and adsorption site. Using these methods, we investigated the effects of -CH₃, -CH₂OH, hydroxyl, and cyano groups on mercury adsorption performance at various sites on carbon surfaces. The results indicate that cyano groups significantly enhance mercury adsorption, while hydroxyl groups exhibit specific effects at different sites. Additionally, we proposed interaction mechanisms for two types of dual functional groups—linear superposition and synergistic effects. This study addresses the current gap in understanding the properties of functional groups related to mercury adsorption and provides a more comprehensive theoretical basis for technologies aimed at efficient mercury adsorption under complex practical conditions.

245. 题目: The efficacy of bioretention systems amended with iron-modified biochar for the source-separated and component-specific treatment of rainwater runoff: A microbiome perspective
文章编号: N24122104
期刊: Journal of Environmental Management
作者: Longfei Wang, Yuan Tian, Jie Sun, Yi Li, Zhengjian Yang
更新时间: 2024-12-21
摘要: Bioretention systems offer advantages in controlling non-point source pollution from runoff rainwater. However, the systems frequently encounter challenges, including insufficient stability of nitrogen and phosphorus removal. Limited research has been performed on bioretention systems which integrate actual data from non-point source pollution cases for the quantitative and qualitative refinement of initial and non-initial rainwater. Moreover, the potential linkages between amended media and microbial communities in bioretention systems with the addition of novel functional filler have not been explored. In this study, a system for treating both initial and non-initial rainwater was established through measurements including iron-modified biochar (FeBC) packing and the optimization of the layer structures. In system treating initial rainwater, the systems loaded with FeBC maintained stable NH4+-N and NO3−-N removal rates of over 95% and 80%, respectively under 12 rainfall simulation events. After a 10-day antecedent drying duration (ADD), the removal rates for NH4+-N and PO43--P remained above 78% and 85%. In systems designed to process non-initial rainwater, increasing the height of the transition layer effectively enhanced the NH4+-N removal stability. Meanwhile, increasing the height of the drainage layer could promote PO43--P removal rates to over 75%. The addition of FeBC facilitated the growth of certain denitrifiers improved overall NO3−-N removal during successive rainfall events. The microbial communities may adapt to variations in the external environment by enhancing the synthesis of ribosome and the metabolism of pyrimidine and purine, further improving the stability of NH4+-N removal. This study provides a theoretical basis for the precise enhancement of nitrogen and phosphorus removal and the design of bioretention systems for differentiated treatment of rainwater, guiding their design and applications in different regions.

246. 题目: TG-MS Analysis for Elemental Composition of Organic Matters and Their Structural Properties
文章编号: N24122103
期刊: Analytical Chemistry
作者: Lin Lin, Sasha Yang, Fuhong Zhang, Muxin Liu, Dong Liu, Lei Shi
更新时间: 2024-12-21
摘要: A novel approach for determining the elemental content of organic matter through thermal gravimetric analysis coupled online with a mass spectrometer (TG-MS) is disclosed. This method not only yields results equivalent to ASTM analysis but also provides insight into the covalent bond structure within the sample. The principle of this technique consists of the combustion of organic matter in an oxygen-enriched environment within the thermogravimetric (TG) system. The gases generated during combustion, including carbon-containing gases such as CO₂ and CO, hydrogen-containing gases such as H₂O, nitrogen-containing gases such as NO₂ and NO, and sulfur-containing gases such as SO₂, are then analyzed using online MS. Quantitative analysis of these gases is accomplished via an external standard method, facilitating the determination of the elemental content of the organic matters. The experiment employed a temperature-programmed heating rate of 10 °C/min, a carrier gas flow rate of 100 mL/min, and an oxygen concentration of 50% by volume. We conducted tests on a range of 23 samples, including coal, heavy oil, oil shale, and biomass. The results for coal, oil shale, and biomass samples were consistent with ASTM standards, while the heavy oil samples demonstrated slightly lower values compared with ASTM methods. Furthermore, we probed into the mass loss and gas generation processes that occur during the combustion of samples, and these results enhance the understanding of the mechanism of organic matter combustion as well as that of the covalent bond structure of organic matters.

247. 题目: Photochemistry of dissolved organic matter derived from compost
文章编号: N24122102
期刊: Science of the Total Environment
作者: Ziling Xiao, Jingyan Zhang, Yilang Qin, Bin Xi, Xiangyang Zhou, Xiuna Ren, Quan Wang
更新时间: 2024-12-21
摘要: The extensive application of compost to enhance soil quality highlights the crucial role of dissolved organic matter (DOM) derived from compost in both terrestrial and aquatic ecosystems, influencing carbon cycling and the fate of contaminants. However, the photochemical behavior of compost-derived DOM (DOMCOM) remains poorly understood. In this study, we investigated the photochemical transformation and photoactivity of DOM derived from typical composts produced from cow manure (CDOM) and pig manure (PDOM). The results indicated that the initial CDOM exhibited higher molecular weight, aromaticity, humification, and photoactivity compared to PDOM. Under UV irradiation, both DOMCOM underwent photobleaching and photo-humification, resulting in a decrease in the average molecular weight by 23.68 % for CDOM and 3.82 % for PDOM, with CDOM being particularly affected. Meanwhile, 2D-COS analysis revealed that the fulvic-like fluorescence fraction was first to respond to photoirradiation in both DOM, followed by the protein-like and microbial humic-like fluorescence fractions, which showed contrasting response trends in CDOM and PDOM. Furthermore, CDOM with a higher concentration of humic-like substances efficiently generated 3DOM*, 1O2 and •OH (4.09 × 10−8, 1.17 × 10−8 and 7.05 × 10−12, respectively) under UV radiation, which were apparently greater than those produced by PDOM (3.30 × 10−8, 8.38 × 10−9 and 4.99 × 10−12, respectively).

248. 题目: Seasonal and spatial pattern of dissolved organic matter biodegradation and photodegradation in boreal humic waters
文章编号: N24122101
期刊: Biogeosciences
作者: Artem V Chupakov, Natalia V Neverova, Anna A Chupakova, Svetlana A Zabelina, Liudmila S Shirokova, Taissia Ya. Vorobyeva, Oleg S Pokrovsky
更新时间: 2024-12-21
摘要: . Studying the competitive effects of microbial and light-induced transformation of dissolved organic matter (DOM) and trace metals is crucially important for understanding the factors controlling aquatic carbon (C), micronutrient and toxicant transformation in boreal waters. Here we determined the biodegradability and photodegradability of DOM and their effects on the behavior of dissolved trace metals in humic surface waters from the European subarctic: an ombrotrophic peat bog continuum (subsurface water–peatland pool–stream) and a stratified forest lake across seasons. Along the bog water continuum, the biodegradation rate was the highest in subsurface waters and the lowest in the acidic peatland pool. Photodegradation was similar for subsurface waters and the stream but was not detectable in the peatland pool. The waters of the forest lake exhibited a strong seasonal effect of biodegradation, which was the highest in October and the lowest in June. Overall, the biodegradation was capable of removing between 1 % and 7 % of initial dissolved organic carbon (DOC), being the highest in the forest lake in October and in the peatland pool in summer. Photolysis was capable of degrading a much higher proportion of the initial DOC (10 %–25 %), especially in the forest lake during June and the bog stream during July. Only a few trace metals (TMs) were sizably affected by both photodegradation and biodegradation of DOM (Fe, Al, Ti, Nb and light rare-earth elements (REEs)), whereas V, Mn, Co, Cu and Ba were affected solely by biodegradation. A likely mechanism of metal removal was their co-precipitation with coagulating Fe(III) hydroxides. Compared to typical CO2 emissions from inland waters of the region, biodegradation of DOM can provide the totality of CO2 evasion from lake water surfaces, whereas biodegradation and photodegradation are not sufficient to explain the observed CO2 fluxes in the bog water continuum. Overall, these results demonstrated strong spatial and seasonal variability in biodegradation and photodegradation of DOM and organic TM complexes, and we call for the need for a systematic assessment of both processes across seasons with high spatial resolution.

249. 题目: Effect of intracellular algal organic matter and nitrate on disinfection byproduct formation in chlorinated water after UV/H2O2 and UV/Cl2 advanced oxidation processes
文章编号: N24122007
期刊: Environmental Science: Water Research & Technology
作者: Fateme Barancheshme, Olya S Keen
更新时间: 2024-12-20
摘要: Advanced oxidation processes (AOPs) are one of the highly effective alternatives for treatment of algal toxins in drinking water. Water that contains algal toxins commonly has organic matter of algal origin and elevated nitrate. Organic matter undergoes transformation during advanced oxidation processes and may change in a way that increases disinfection byproduct (DBP) formation when water is chlorinated post-AOP. Nitrate forms reactive nitrogen species under certain UV wavelengths that can also interact with organic matter and change its properties in a way that increases post-AOP DBP formation. Two types of advanced oxidation process (UV/H2O2 and UV/Cl2) were compared in their ability to change the formation potential of regulated DBPs [four trihalomethanes (THMs) and nine haloacetic acids (HAAs)] and an unregulated nitrogenous DBP (N-DBP) N-nitrosodimethylamine (NDMA) due to the interaction of the process with algal organic matter (AOM) and nitrate in the water. The two AOPs showed no difference in post-treatment DBP formation under any of the tested conditions. Higher levels of treatment with both processes led to slightly higher formation potential of some THMs. AOM made a poor precursor for additional THMs and three HAAs (six not consistently detected), but had a higher NDMA yield than background organic matter (0.59 ng/mg-C vs. 0.18 ng/mg-C, p = 0.038). Nitrate suppressed chlorinated THMs and favored increased concentrations of brominated THMs and HAAs, resulting in higher percent incorporation of background bromide into DBPs. Moreover, nitrate addition (20 mg-N/L of added nitrate compared to the background level of 0.47 mg-N/L) led to 11 times higher NDMA formation. Formation of N-DBPs during post-AOP chlorination in the presence of AOM and nitrate warrants additional investigation.

250. 题目: Nitrogen-doped porous hydrochar for enhanced chromium(VI) and bisphenol A scavenging: Synergistic effect of chemical activation and hydrothermal doping
文章编号: N24122006
期刊: Environmental Research
作者: Jianhua Qu, Fansong Meng, Fuxuan Bi, Zhao Jiang, Mengning Wang, Qi Hu, Yupeng Zhang, Hui Yu, Ying Zhang
更新时间: 2024-12-20
摘要: Nitrogen-doped porous hydrochar (NPHC) was successfully synthesized by hydrothermal carbonization and activation with KHCO₃, which was employed for scavenging hexavalent chromium (Cr(VI)) and bisphenol A (BPA) in contaminated water. N doping increased the unique active sites such as amino and molecular N in NPHC for adsorbing contaminants, and enhanced the activation effect. Compared to original (HC) and N-doped hydrochar (NHC), the S_BET of material improved from 3.99 m²/g and 4.71 m²/g to 1176.77 m²/g. Meanwhile, NPHC exhibited more superior adsorption capacity for Cr(VI) (323.25 mg/g) and BPA (545.34 mg/g) than that of porous hydrochar (213.17 and 343.67 mg/g). Moreover, NPHC possessed pH-dependence and presented more excellent tolerance for interfering ions and regeneration performance. Notably, the Cr(VI) capture by NPHC was dominated via pore filling, electrostatic interaction, reduction, and complexation, while π-π stacking, H-bond interaction, and hydrophobic action were relevant to the binding mechanism of BPA. Overall, the proposed functionalization strategy for biochar was conducive to enhance the remediation of water bodies.

251. 题目: Mineral and Microbial Properties Drive the Formation of Mineral-Associated Organic Matter and Its Response to Increased Temperature
文章编号: N24122005
期刊: Global Change Biology
作者: Jianing Zhao, Xuehui Feng, Jie Hu, Mei He, Siyu Wang, Yuanhe Yang, Leiyi Chen
更新时间: 2024-12-20
摘要: A comprehensive understanding of the formation of mineral-associated organic matter (MAOM) is a prerequisite for the sustainable management of soil carbon (C) and the development of effective long-term strategies for C sequestration in soils. Nevertheless, the precise manner by which microbial and mineral properties drive MAOM formation efficiency and its subsequent response to elevated temperature at the regional scale remains unclear. Here, we employed isotopically labelled laboratory incubations (at 15°C and 25°C) with soil samples from a ~3000 km transect across the Tibetan Plateau to elucidate the mechanisms underlying MAOM formation and its temperature response. The results indicated that both mineral protection and microbial properties were critical predictors of MAOM formation across the geographic gradient. The efficiency of MAOM formation was found to increase with the content of iron (Fe) oxides and their reactivity [i.e., the ratio of poorly crystalline Fe oxides to total Fe oxides (Fe_o:Fe_d)] but to decrease with the relative abundance of Gammaproteobacteria and Actinobacteria across the plateau. Moreover, a notable decline in MAOM formation efficiency was observed under elevated temperatures, which was concomitant with a reduction in the content and reactivity of Fe oxides, as well as the microbial assimilation of the labelled substrate. The attenuation of mineral–organic associations was identified as the primary factor contributing to the warming-induced reduction in MAOM formation. These findings highlight the necessity of incorporating organo–mineral associations and microbial properties into Earth System Models to accurately project soil C dynamics under changing climate.

252. 题目: Microbial-derived C increased more than plant-derived in soil under plantation versus grassland 11 years after landslide
文章编号: N24122004
期刊: Journal of Soils and Sediments
作者: Xia Wang, Wenhui Duan, Zhiguo Hao, Huawei Zhu, Jieyi Xia, Jia Li, Junwu Wang, Yujin Chen, Yunfei Zhao
更新时间: 2024-12-20
摘要:

Purpose

Vegetation restoration can improve soil carbon (C) sink capacity, and is considered an effective approach for restoring degraded ecosystems. As an important component of soil organic carbon (SOC), microbial- and plant-derived C affect the size and turnover of the SOC pool; however, the effects of different vegetation types on SOC sequestration capacity remains controversial due to the lack of long-term systematic observations in restoration areas.

Materials and methods

Amino sugars and lignin phenols (as biomarkers of microbial- and plant-derived C, respectively), together with several soil basic physicochemical properties in the topsoil (0–10 cm) and subsoil (40–50 cm) were investigated in an afforested (AF) and naturally restored grassland (NRG) of a shallow landslide ecological restoration area in the Bailong River Basin, China, following 11 years of restoration.

Results and discussion

In the topsoil, SOC sequestration efficiency of AF was 28.18% higher than that of NRG; Whereas AF was 6.69% lower than NRG in the subsoil. Further, the enrichment of amino sugars in soil was more favorable to SOC accumulation than lignin phenols, and the environmental factors affecting SOC and amino sugar accumulation showed relative uniformity. The more suitable environment for microbial survival within AF regions promoted the decomposition of lignin phenols, and increased the contribution of microbial-derived C to SOC compared with NRG; Further, the more stable SOC components in AF facilitated its resistance to external disturbances.

Conclusions

Our results demonstrated when compared with NRG, the contribution of plant-derived C to SOC was lower in the AF plots, while the contribution of microbe-derived C was both higher and more stable. These results provide novel information regarding the accumulation pathways of SOC in shallow landslide areas, and emphasize the importance of microbial-derived C in SOC sequestration, as well as suggesting that AF is more effective than NRG in SOC sequestration.

253. 题目: Deciphering the mechanism of microbial metabolic function shift and dissolved organic matter variation in acidogenic fermentation of waste activated sludge induced by antiviral drugs.
文章编号: N24122003
期刊: Journal of Environmental Management
作者: Ruming Wang, Zhuoqin Wang, Chunxing Li, Jiamiao Chen, Nanwen Zhu
更新时间: 2024-12-20
摘要: Antiviral drugs (ATVs), as emerging contaminants enriched in wastewater activated sludge (WAS) in wastewater treatment plants, affect subsequent treatment. ATVs have been shown to have negative influences on anaerobic digestion of WAS, but it is unclear how ATVs affect functional microbial metabolic activity and changes in intermediates. Thus, the effect of the anti-HIV drug ritonavir (RIT) on the period of anaerobic fermentation (AF) and the response of microbial community structure were examined in this study. Results indicated that the production of total volatile fatty acids (VFAs) decreased from 2010.21 mg/L to 372.03 mg/L under 125-1000 μg RIT/kg TSS treatment. Characterization of organic matters revealed that dissolved organic matter in the high-dose RIT groups was less biodegradable, with lower protein content and higher humus content. Mechanistic analyses indicated that RIT exposure reduced the abundance of hydrolyzers and inhibited carbohydrate metabolism, resulting in an increased humification index in the RIT groups. In addition, the expression of genes associated with the synthesis of VFAs was also significantly reduced in the RIT groups, leading to a decrease in both the amount and type of VFAs. This study provides a novel perspective on the effects of emerging contaminants on WAS treatment processes and pollution prevention.

254. 题目: Elucidation of ammonium and nitrate adsorption mechanisms by water hyacinth biochar: effects of pyrolysis temperature
文章编号: N24122002
期刊: Environmental Science and Pollution Research
作者: Yudai Kohira, Desalew Fentie, Mekuanint Lewoyehu, Tassapak Wutisirirattanachai, Ashenafei Gezahegn, Solomon Addisu, Shinjiro Sato
更新时间: 2024-12-20
摘要:

Numerous studies indicate biochar’s nitrogen (N) adsorption capacity plays a crucial role in soil N retention. However, there is limited understanding on inorganic N adsorption mechanisms in biochar derived from aquatic weeds such as water hyacinth (WH). This study investigated ammonium-N (NH₄⁺-N) and nitrate-N (NO₃^–-N) adsorption capacities and mechanisms of WH biochar pyrolyzed at different pyrolysis temperatures of 400 °C, 600 °C, and 800 °C (BC400, BC600, and BC800, respectively). Results showed NH₄⁺-N adsorption was maximized (1.07–1.09 mg g^–1) with BC400 at initial solution pH 7.0–9.0, while NO₃⁻-N adsorption peaked (0.80 mg g^–1) with BC800 at initial solution pH 5.0. Both NH₄⁺-N and NO₃^–-N followed well the Pseudo-second-order model in adsorption kinetics (R² = 0.990–0.997 and 0.962–0.992, respectively). The Sips model accurately described the adsorption isotherms for NH₄⁺-N (R² = 0.994–0.999) and NO₃^–-N (R² = 0.992–0.999). The calculated maximum adsorption capacity for NH₄⁺-N and NO₃^–-N using Sips model was 11.2–16.8 mg g^–1 and 0.693–4.99 mg g^–1, respectively. Co-existing cations and anions reduced NH₄⁺-N and NO₃^–-N adsorption capacity, respectively, with other ions with higher valence exhibiting higher inhibition effects (43%–97% and 44%–73%, respectively). Primary adsorption mechanism for NH₄⁺-N included cation exchange via oxygen-containing surface functional groups in BC400 and pore filling and surface struvite precipitation in BC800. Major adsorption mechanisms for NO₃^–-N included electrostatic interactions in BC400 and pore filling in BC800. These findings suggested that biochar derived from aquatic weeds possessed the same potential usefulness for soil N retention as biochar from other feedstocks, and that it might assist for further detailed considerations in other studies for biochar soil application.

255. 题目: Three-dimensional Fluorescence Spectrum Characteristics and Source Analysis of Dissolved Organic Matter in Sewage Outfall into the Sea of Dongguan
文章编号: N24122001
期刊: Water, Air, & Soil Pollution
作者: Changzheng Wu, Jinquan Wan, Jinpeng Wang, Jinlan Cai, Xiuwen Ren, Yan Wang, Zhangqing Bi
更新时间: 2024-12-20
摘要:

The composition and source analysis of dissolved organic matter (DOM) in sewage outfall into the sea is an effective means of pollutant traceability, which is of great significance to the ecological environment protection in coastal areas. This paper selects Dongguan, an important coastal industrial city in China’s Pearl River, for research. Water samples from 42 sewage outfalls into the sea were measured by three-dimensional fluorescence spectroscopy (3D-EEM). Combined with fluorescence characteristic parameters, similarity analysis and parallel factor analysis (PARAFAC), the spectral characteristics, DOM composition and source were analyzed. The average values of fluorescence parameters fluorescence index (FI), biological index (BIX) and humification index (HIX) were 1.80, 0.94 and 0.55, respectively. The overall PARAFAC analysis found that DOM in the sewage outfall of Dongguan was mainly composed of two fluorescent components, namely tyrosine-like (C1) and humus-like (C2), where tyrosine-like fluorescence was higher than humus-like. This indicates that DOM comes from both terrestrial and endogenous biological activities, but endogenous sources are the primary sources. The similarity analysis divided sewage outfalls into four categories, namely urban rainwater drainage characteristics, typical urban sewage, Jiulong paper-related wastewater and aquaculture water in fish ponds. At the same time, in the PARAFAC analysis, the fluorescence components of 14 urban rainwater outfalls were consistent with the overall analysis results. There are 3 effective parallel factor fluorescence components in 23 outfalls most likely to be contaminated by domestic sewage, namely tyrosine (C1) Humus-like (C2) and tryptophan (C3), C3 components in the characterization of the protein fluorescent tryptophan substance region appeared a strong response peak, belonging to the source pollution, consistent with similarity analysis results. This study suggests that the same source sewage outfalls should be classified management, strengthen the source tracing of sewage outfalls into the sea in neighboring cities, and build a collaborative pollution control system for river basins, estuaries and coastal.

256. 题目: MOF biochar composites for environmental protection and pollution control
文章编号: N24121920
期刊: Bioresource Technology
作者: Samaneh Ghaedi, Hamid Rajabi, Mojgan Hadi Mosleh, Majid Sedighi
更新时间: 2024-12-19
摘要: Research studies on Metal Organic Frameworks (MOF) based composites and their potential applications in environmental engineering and pollution control have recently emerged. An attractive material to form MOF composites is biochar (BC); a low-cost, highly porous carbonaceous by-product of biomass pyrolysis. This paper presents a critical review on MOF-biochar composites, focusing on fabrication, characterisation, modification, and applications in environmental protection and pollution control. The adsorption mechanisms and influential parameters are systematically examined to develop an insight into interactions between MOF and biochar in remedial process. The adsorption capacity of composites is generally doubled compared to the standalone biochar, while MOFs maintain their crystallinity, even over multiple regeneration cycles, indicating the composites’ long-term applicability and sustainability. These findings highlight the potential of MOF-biochar composites for environmental applications and identify key areas for further research to enhance their sustainability in environmental protection and green energy.

257. 题目: A sustainable approach to enhancing humic acid production from lignocellulose via green alum
文章编号: N24121919
期刊: Journal of Environmental Chemical Engineering
作者: Jinting Su, Ziyun Liu, Lixin Zhao, Lili Huo, Weiming Yi, Zhihe Li, Lihong Wang, Zonglu Yao
更新时间: 2024-12-19
摘要: Artificial humic acid (A-HA) produced from biowaste via hydrothermal conversion demonstrates as a promising advanced soil organic matter supplement. However, its low production yield, and poor physicochemical properties, such as high molecular weight and inert function groups, limit the practical application. This study investigated the potential of green vitriol (GV) on stimulate A-HA production and modify the its qualities. The yield of A-HA increased from 21.87 wt% to 27.84 wt% with a ratio of biomass to GV was 6 at 220°C, while the optimum proportion of A-HA in hydrochar was increased by 13.57 ± 11.06 wt% compared to the control at a temperature of 280°C and a 3:1 addition ratio. In addition, the A-HA molecular weight decreased, and oxygen-containing functional groups (i.e., hydroxyl and carboxyl groups) increased with GV addition, enhancing its the reactivity and hydrophilicity. The related promotion mechanism was proposed, which the oxidative decomposition and humification of difficult-to-break-down substances facilitated by hydroxyl radical(·OH) from the Fenton-like reaction of GV with water. This study helpfully presents a novel strategy for promote production of sustainable and high-quality A-HA.

258. 题目: Fertilization of potentially toxic element-contaminated soils remediated with reusable biochar pellets using rice straw, pig manure and their derived biochar
文章编号: N24121918
期刊: Environmental Pollution
作者: Yi Wu, Zongwei Wang, Ziyu Xue, Yuhang Yan, Bushra Huma, Yuqian Zhou, Zhongxin Tan
更新时间: 2024-12-19
摘要: Potentially toxic elements (PTEs) are widespread pollutants in agricultural fields, presenting significant challenges to the maintenance of soil ecological functions while simultaneously reducing their concentrations. This study detailed the development of a high-strength reusable silicate magnetic composite biochar sphere (SMBCS) characterized by superior magnetic and adsorption properties, synthesized from natural minerals and biochar. The application of SMBCS over three consecutive remediation cycles led to reductions in cadmium (Cd), lead (Pb), and arsenic (As) concentrations in soil by 28.6%, 26.6%, and 42.9%, respectively, accompanied by corresponding decreases in bioavailability of 52.7%, 49.4%, and 39.4%. The accumulation of Cd, Pb, and As in rice seedlings cultivated in the remediated soil decreased by 79.50-85.47%, 38.05-38.99%, and 39.56-77.10%, respectively. However, the removal of essential mineral nutrients (Al, Fe, K, Ca, Mg, Si, N, Zn, Mn, and Cu) from the soil ranged from 3.26% to 36.28%, which adversely affected seed germination and rice seedling growth. Pre-planting fertilization with rice straw (RS), pig manure (PM), biochar (RSB and PMB), and regenerated SMBCS (RSMBCS1 and RSMBCS2) effectively reduced Cd (0.20-45.40%) and Pb (8.70-35.36%) uptake while enhancing the bioavailability of mineral nutrients, thereby promoting crop growth and physiological traits. The SMBCS-fertilization technique emerges as a viable approach for the removal of PTEs in agricultural soils, facilitating the restoration of ecological functions and ensuring safe agricultural production.

259. 题目: Reductive Dissolution Mechanisms of Manganese Oxide Mediated by Algal Extracellular Organic Matter and the Effects on 17α-Ethinylestradiol Removal
文章编号: N24121917
期刊: Environmental Science & Technology
作者: Zhicheng Liao, Huan He, Feiyuan Liu, Jingye Cui, Ziwei Guo, Danni Cui, Bin Huang, Hongwen Sun, Xuejun Pan
更新时间: 2024-12-19
摘要: Reductive dissolution of manganese oxide (MnO_x) is a major process that improves the availability of manganese in natural aquatic environments. The extracellular organic matter (EOM) secreted by algae omnipresent in eutrophic waters may affect MnO_x dissolution thus the fate of organic micropollutants. This study investigates the mechanisms of MnO_x reductive dissolution mediated by EOM and examines the effects of this process on 17α-ethinylestradiol degradation. The influences of EOM concentration (1.0–20.0 mgC/L) and pH (6.0–9.0) in both dark and irradiated conditions were assessed. In the dark, EOM was found to facilitate MnO_x reductive dissolution via the ligand-to-metal charge transfer (LMCT). The dissolution was further enhanced under irradiation, with the participation of superoxide ions (O₂^•–). Higher EOM concentrations increased the contents of available reducing substances and O₂^•–, accelerating the reductive dissolution. Higher pH slowed the photoreductive dissolution rates, while O₂^•–-mediated reduction became more important. Polyphenols and highly unsaturated carbon and phenolic formulas in EOM were found to drive the reductive dissolution. Soluble reactive Mn(III) formed through reductive dissolution of MnO_x effectively removed 17α-ethinylestradiol in solution. Overall, the findings regarding the mechanisms behind reductive dissolution of MnO_x have broad implications for Mn geochemical cycles and organic micropollutant fate.

260. 题目: The importance of organic matter in controlling the metal variability and mobility in seagrass sediments
文章编号: N24121916
期刊: Environmental Pollution
作者: Shanshan Chen, Shiquan Chen, Zhenghua Tao, Yanping Li, Paolo Magni, Li Zhang, Xinqing Zheng, Ke Pan
更新时间: 2024-12-19
摘要: Metal contamination in seagrass beds has been extensively studied in the past decades. Most of earlier studies have focused on reporting metal concentration in different compartments of seagrass ecosystem, with little attention given to the role of sediment organic matter in controlling the metal mobility and bioavailability. This study investigated metal contamination in seagrass sediments in Hainan Island, China and illustrated how various geochemical factors impact the spatial variability of the metal concentrations. Particularly, we explored how organic matter influence metal storage and mobility in the seagrass sediments. The enrichment of metals in these sediments was not only associated with levels of organic matter but also their sources. The organic matter content showed positive correlations with both metal concentrations and acid-extractable fractions of chromium, silver, and cadmium, highlighting its significant role in influencing metal accumulation and mobility in sediments. Overall, this research enhances our understanding of metal cycling within seagrass ecosystems and highlights the vital role of seagrass-derived organic matter in regulating metal dynamics.