环境•农林最新文献

The rapid increase in tropospheric ozone levels, exceeding the phytotoxic threshold (40 ppb), threatens crop yields in India's Indo-Gangetic plains, necessitating the exploration of antiozonants. Biochar application offers a promising, low-risk solution to mitigate the harmful effects of ozone and other abiotic stressors on agriculture. This study investigates the ameliorative effects of biochar amendments (2.5 and 5%) on selected mung bean cultivars (HUM-1 and HUM-6) under elevated ozone (ambient + 20 ppb). Biochar amendments improved foliar characteristics and reduced chlorotic and necrotic spots generated by elevated ozone. Reductions led by ozone in the growth and root-shoot ratio were significantly mitigated in biochar-treated plants. Despite decreased nodulation, the size and biomass of individual nodules increased under biochar treatments. Under ozone stress, the HUM-1 cultivar allocated more photosynthetic assimilates to vegetative parts of the plant, whereas, the HUM-6 cultivar directed greater photosynthates to reproductive structures. Floral and fruit characteristics improved in both cultivars after biochar supplementation, indicating enhanced carbon allocation towards reproductive parts. Biochar treatments also alleviated seed shriveling and size reduction observed under ozone stress, improving seed quality. Biochar amendment was more beneficial in yield protection of sensitive cultivar (HUM-1) than less sensitive cultivar (HUM-6). Findings of the present study suggested that biochar applications of 2.5% and 5% have significant potential to mitigate the adverse impact of ozone on mung bean plants. This study underscores the potential of biochar as a viable agronomic intervention to enhance crop resilience against tropospheric ozone, contributing to food security and sustainable agriculture in the context of climate change.

This study aims to determine the abundance and distribution of organic pollutants in the coastal areas of Mt. Vechernyaya (Enderby Land, East Antarctica). For this purpose, soil and sediment samples were collected from the vicinity of the old Soviet field base and lakes. The field studies were conducted within the 14th Belarusian Antarctic Expedition between January and February 2022. The collected samples were analyzed for 16 polycyclic aromatic hydrocarbons (PAH), 7 polychlorinated biphenyls (PCB), and 11 organochlorine pesticides (OCP) by GC–MS/MS. Particle size distributions and total organic carbon levels of the samples were determined to evaluate the measured pollutant concentrations. The total PAH, PCB and OCP levels measured in the samples were 6.0–92 µg/kg, 25–422 ng/kg and 2.3–1383 ng/kg, respectively. The results pointed out petrogenic PAH sources for lake sediment while pyrolytic sources were estimated for soil samples due to the use of fossil fuels in generators. While detected PCBs may originate from local sources due to legacy use, OCPs have been suggested to reach from the mainland by long-range atmospheric transport. The measured levels will provide a baseline which will help to monitor possible future changes in the region.

Limited research on sulfur-metabolizing microorganisms and their functional genes in shale gas wells has hindered a comprehensive understanding of corrosion mechanisms in gathering pipelines. We conducted an analysis of the physicochemical water parameters at various stages, specifically examining clear water, flowback liquid, and produced water. Concurrently, we investigated the microbial community structure and examined the composition of sulfur metabolism function genes. The results indicate that, in the clear water sample, Nitrincola (CysP) constituted 6.52% and Desulfuromonas (CysA) 3.11% as the main genera. In the return flow stage, Marinobacterium and Marinobacter played a major role (CysA, CysI and CysJ). In the initial production stage, Shewanella (CysN and CysD) had a high abundance, reaching 34.08%. Two months after the start of production, Desulfuromonas (CysA) and Hyphomonas (CysH) were dominant, with abundances of 2.66% and 0.01%, respectively. Notably, the concentrations of S²⁻ and SO₄²⁻, were found to be closely associated with the variations in these sulfur-metabolizing functional genes. During the late flowback and production phases, these microorganisms exerted the most significant influence on pipeline corrosion. In summary, this study elucidated the dynamic changes in sulfur-metabolizing microorganisms and their functional genes in water samples collected at various stages of shale gas extraction. By analyzing the role of these sulfur-metabolizing functional genes in the corrosion processes of gathering pipelines, the research offers a novel perspective on developing anti-corrosion strategies for shale gas pipelines.

Microplastics (MPs) pose significant environmental and health risks due to their persistence, ability to adsorb toxic chemicals, and widespread distribution in aquatic environments. Despite advancements in water treatment technologies, finding a method that is not only efficient and effective but also affordable for removing MPs especially polypropylene (PP) MPs from wastewater has been a significant challenge. This study investigates the use of electrocoagulation (EC) as an economical and sustainable solution to address this challenge. Using Central Composite Design (CCD), the EC process was optimized for PP MPs removal, achieving a maximum efficiency of 97% under optimal conditions: a pH of 7.7, current density of 11.7 A/m², and NaCl concentration of 1 g/L. The study also evaluates the impact of factors like particle size, electrode configurations, and MP types, including polyethylene (PE), styrene-butadiene rubber (SBR), and waste rubber (WR), on removal efficiency. Results reveal that all MP types were removed with over 90% efficiency. Notably, MPs derived from thermoplastics like PP and PE were removed more efficiently than rubber-based microparticles like SBR and WR. Moreover, the estimated operational cost of removing PP MPS was approximately $0.23 per cubic meter of treated water, highlighting the cost-effectiveness of EC process for wastewater treatment.

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Remediation of eutrophic water is a challenging task. Modification of biochar has been demonstrated to enhance the removal ability of contamination of biochar. In this work, magnesium (Mg) and copper (Cu) were incorporated in biochar during preparation to increase the removal of phosphate (P) and inhibit algae bloom. The results showed that Mg-modification significantly (p < 0.05) improved the adsorption of phosphate, and the adsorption capacity was 138.7 mg g⁻¹, and the improvement on P removal was attributed by the formation of MgO which enhanced the sorption affinity on PO₄³⁻. In addition, Cu-modification showed significant (p < 0.05) inhibition effect on growth of cyanobacteria as compared to original biochar with biomass decrease of 62% for Cu-biochar and 85% for Cu-Mg-biochar after three week incubation. Among all modified biochar composites, Cu-Mg-biochar showed highest inhibition effect due to the removal of nutrient and directly causing cell lysis. Moreover, in the water co-existing with different ratios of oil and PO₄³⁻, Cu-Mg-biochar showed highest (p < 0.05) efficiency in inhibition on the growth of toxic cyanobacteria, biomass decreased from 2.85 mg L⁻¹ to 0.20 mg L⁻¹. Overall, Cu-Mg-biochar composite was suggested effective remediation material in treating oil-impacted eutrophic water.

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Water contamination by synthetic organic compounds is one of the major environmental issues facing the world today. Among the available methods to treat them, catalytic advanced oxidation processes using Cu(II) ions to activate peroxymonosulfate is a potential candidate at slightly alkaline conditions (pH 8). In this work, we investigated the influence of PMS concentration (0–1000 μmol L^–1), solution pH (7–10), and the effect of water matrix (ultrapure, tap, and simulated municipal wastewater—SMWW) on imidacloprid (IMD) insecticide oxidation. After optimization of the investigated variables (500 μmol L^–1 PMS and pH 8), almost complete IMD oxidation was achieved in 6 h using ultrapure and tap water. The main detected byproducts resulting from IMD oxidation in ultrapure water are due to hydroxylation reactions and rupture of the imidazolidine ring. When SMWW was used, IMD oxidation was only 10% in 6 h, probably due to the scavenging effect of inorganic and organic compounds. The main produced working oxidants were radical (mainly HO^● and SO₄^●–) and non-radical (¹O₂, Cu(I), and Cu(III)) species, based on scavenging experiments and mass spectrometry detection of produced DMPO byproducts. Among these, HO^● species seems to promptly oxidize IMD.

The present study investigates the need to improve photocatalytic processes for the treatment of textile effluents, which are traditionally reliant on ultraviolet radiation, which is impractical on an industrial scale. Therefore, enhancing efficiency in the visible spectrum is crucial. This study emphasizes the importance of the synthesis methodology in the creation of gold nanoparticles (Au-NPs) to boost their photocatalytic activity via electron transfer and surface plasmon resonance. This study explores the synthesis of modified Au-NPs on TiO₂ using precipitation deposition (PD) and modified wet impregnation (MWI) techniques. Results showed that MWI synthesis yields catalysts with greater surface area and smaller particle sizes than PD, enhancing the photocatalytic efficiency, and achieving 100% dye removal in less than 90 min, and a reduction in total organic carbon (TOC) of more than 70%. Photocatalytic degradation tests under solar and visible light reveal that MWI-derived catalysts outperform PD-derived ones in reducing RB5 dye. The analysis of active species involved in the redox reactions identified h⁺, ^{− •}O₂, e⁻, and ^•OH radicals as contributors to the degradation of the organic pollutant RB5, with photogenerated holes being the primary active species in the photocatalytic process, followed by hydroxyl radicals. Thus, it was possible to confirm the important role of gold nanoparticles in the enhancement of the photocatalytic activity.

Microplastics (MPs), though often invisible to the naked eye, pose a significant and pervasive environmental threat, subtly integrating into natural systems and disrupting ecological balance. Ingestion of MPs at different trophic levels has been widely documented, but their impacts on zooplankton have been under-studied despite their vital ecological roles in marine food webs. In this study, MPs were determined in popular seafood Acetes shrimps (Acetes chinensis and A. erythraeus) from the southeastern coast of Bangladesh. The entire body of the shrimps (500 individuals of each species) underwent comprehensive MP analysis through aquamation (alkaline hydrolysis), microscopic examination and polymer identification by Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscope (ATR-FTIR). A total of 67 and 110 particles were visually identified, among which 39 and 51 particles were determined as MPs using ATR-FTIR in A. erythraeus and A. chinensis, respectively, averaging 0.078–0.102 particles per species. This study encountered various colours, shapes, and types of MPs, among which white/transparent (49–59%), filamentous (76–82%), and fiber (76–77%) were prevalent. The study observed a size range of MPs from < 500 µm to 5 mm, with a concentration of 1.33–11.15 items/g biomass. ATR-FTIR analysis identified 37, 25, 11, 9, 5, and 3 polymer particles of Polyethylene, Polypropylene, Polyethylene Terephthalate, Nylon-6 (Polyamide), Ethylene Vinyl Acetate and Polybutylene Terephthalate respectively. The findings of this study have elicited a “wake-up call” on the bioaccumulation of MPs in Acetes shrimps with potential contamination of seafood and public health concerns in the Bay of Bengal region.

Biofuels and the sustainable environment are the two major issues of this century. Natural resources and global environment is depleting and has increased the need for fuel production. Fuels ought to be produced organically, be renewable when used, and require the least amount of energy and chemicals. The method of electrocoagulation is used to produce CO₂ and subsequently transform it into biofuels that are useful sources of energy. Synthetic oily wastewater was used as the source of CO₂ to convert it into long chain hydrocarbons. Using aluminum as a sacrificial anode allowed coagulants to naturally form in the electro-kinetic system. The presented study revealed that precisely controlled parameter in this unique work has made it possible to execute electrochemical conversion. In-situ generation of CO₂ into biofuel molecules through a hierarchal pathway of conversion into alcohols, carboxylic acids and alkyl esters was studied. The sludge's FT-IR analysis was used to look into the long-chain carboxylic acid synthesis, and the GC–MS results later corroborated this. Achieving a cost-effective experiment design and producing energy precursors and electricity through creative treatment were the major accomplishments of the current study. The ultimate goal is to determine how to apply it in the energy and fuel markets for improved oil spill management by scaling up the process from lab to industrial scale in the future.

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