环境•农林最新文献

Parental care in nature can present itself in different forms and vary in intensities and strategies, being maternal care one of the widely observed patterns in animals. In spiders, parental investment is carried out mainly by females. Despite this, newly hatched eggs can still be targets of a series of natural enemies. In a remnant of Atlantic Forest in Brazil, females of the spider Eldar galadrielae sp. nov., family Anyphaenidae, build nests at the forest’s edge by folding plant leaves. However, information about the plants chosen for nest, the importance of maternal care by females in offspring survival, and predators are completely unknown. In this study, we (1) presented new information about the nest built by females of Eldar galadrielae sp. nov.; (2) compared the predation rate on eggs of the spider Eldar galadrielae in nests with and without the presence of the female; (3) provided morphological descriptions and distribution maps to the genus Eldar gen. nov. as well as presenting; and (4) the described Pseudogaurax vasconcellosi sp. nov. as the predator of the spider eggs. This is the first report on an interaction between Pseudogaurax flies and Anyphaenidae spiders. Our results support predation rates higher in female-less Eldar galadrielae sp. nov. nests. Although egg consumption was 100% in nests attacked by flies, overall nest predation rate was low, as flies were only recorded in three of the 12 nests that maintained female care, indicating that active protection of egg sacs by females can increase the offspring’s chances of survival.

Carbon microspheres (CMSs) were synthesized from soluble starch via a straightforward and efficient hydrothermal carbonization process. Soluble starch was chosen as a cost-effective, non-toxic, and sustainable precursor, offering a green approach to the production of carbon microspheres. Two types of amino-functionalized carbon microspheres (NH₂-CMSs) were subsequently prepared via surface amino-modification using aqueous ammonia or ammonium persulfate. Quantitative analysis revealed that NH₂-CMSs modified with ammonia exhibited a surface amino content 2.5 times higher than those modified with ammonium persulfate. Structural and morphological characterizations confirmed the successful synthesis of uniformly sized spherical NH₂-CMSs, with the amino-functionalization maintaining the integrity of the carbon framework. Adsorption studies demonstrated that NH₂-CMSs achieved a significantly enhanced theoretical maximum adsorption capacity of 130.96 mg·g⁻¹ for Pb²⁺, surpassing that of unmodified CMSs (80.87 mg·g⁻¹) by 1.62 times. The primary adsorption mechanism involved the formation of covalent bonds between amino groups and Pb²⁺, resulting in stable metal complexes. The adsorption kinetics indicated a single-molecule adsorption behavior dominated by chemical adsorption as the rate-determining step. These findings underscore the potential of NH₂-CMSs as highly effective adsorbents for the removal of Pb²⁺ from aqueous solutions.

This study aimed to develop agro-based engineered biochars for adsorbing low concentration nitrate with economic and effective characteristics. Two kinds of wheat or corn-straw based biochars were prepared at different pyrolysis temperatures using the acid/iron modification method. The performance of adsorption and desorption, mechanism (adsorption model, biochar morphology, zeta potential), influencing factors (pH, co-existence of anions and organic matter) and stability were comprehensively evaluated. The results showed that the modification by HCl impregnation for corn straw-based biochars (CH500) or HCl-FeCl₃ for wheat-straw based biochar pyrolyzed at 500 °C (WFe500) could reach a NO₃⁻ removal efficiency of 85–91% within 24 - 48 h at a low concentration of 20 mg N L⁻¹. The maximum adsorption capacity (Q_m) from Langmuir model for the CH500 (1958 mg kg⁻¹) was 20% greater than that of WFe500 (1651 mg kg ⁻¹). After the kinetic adsorption reached the equilibrium, there was no clear desorption by DI water. The pH had no significant effect on the adsorption, and the adsorption efficiency of NO₃⁻ could be kept at ~ 60% under the co-existence of anions as well. After acid or iron modification, polarity index of H/C further decreased, and the index of (O + N)/C or O/C further increased. The zeta potential (ζ), the BET surface area and pore volume of CH500 and WFe500 also increased. It was suggested that the modification increased the positive charge loads of H⁺ and Fe³⁺ on the biochar surface, which enhanced polarity and electrostatic attractions and led to increased effective contacts between the biochar and low concentration NO₃⁻. The NO₃⁻ accumulated at the charge sites on the surface and inside the biochar via electrostatic attraction could replace other anion previously fixed on the biochar (such as Cl⁻ loaded by modification) via ion exchange. The increased volumes/areas of internal pores by the modification were crucial for adsorption and retention of NO₃⁻ ions after the effective contact. The modification method, pollutant characteristics and biochar feed stock characteristics should be considered together as primary influencing factors for preparing high performance biochar.

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The environmental effects of industrial wastewater on terrestrial and aquatic ecosystems are a significant global issue. With the growing demand for processed seafood, the seafood processing industry is under increasing pressure to produce more, resulting in greater wastewater discharge into adjacent waterways. This study finds that Salmonella enterica BSE-13, isolated from seafood processing effluent, is highly effective in removing BOD, COD, nitrites, nitrates, and nitrogen. When starch is added, among the 7 isolates BSE-13 achieves higher removal efficiencies of 72.5% for BOD, 65.8% for COD, 41.6% for nitrites, 69.6% for nitrogen, and 54.3% for nitrates. Response Surface Methodology (RSM) using the Box-Behnken Design (BBD) optimized media conditions to maximize the removal efficiency of the potent BSE-13 strain. Under optimized conditions, removal rates reach 83.94% for BOD and 73.15% for nitrogen. In a glass column setup, BSE-13 removes 62.25% of BOD by the 12th day. A pot trial shows that the treated effluent improves plant growth compared to untreated effluent. Toxicity tests reveal significant chromosomal and nuclear abnormalities in onion root tips exposed to untreated effluent, while brine shrimp studies show that treated effluent and controls have fewer aggregates and less morphological change, with untreated effluent causing severe toxicity. Therefore, the results of this study suggest that using eco-friendly microbes for treating effluent offers a cost-effective and environmentally friendly method for cleaning wastewater. Microbially treated effluent demonstrates significant potential for reducing various pollutants and enhancing plant growth.

Olivine is a natural material with abundant reserves and is considered to have the potential to treat heavy metal ions in water. In this study, a facile precipitation-calcination method was employed to deposit micrometer-sized magnesium oxide (MgO) rods onto the surface of olivine powder (PO). This process yielded a cost-effective MgO-modified olivine composite (MgO@PO400), which was subsequently evaluated for its ability to adsorb Cu²⁺ from aqueous solutions. The BET-specific surface area of MgO@PO400 was three times higher than that of PO, and the MgO micro-rods were distributed on the material's surface (BET:Brunauer-Emmet-Teller). Adsorption experiments showed that the data fitted well with the pseudo-second-order kinetic model and the Langmuir isotherm model, which indicated that Cu²⁺ was removed by monolayer chemisorption. In addition, the process was verified to be spontaneous and thermodynamically favorable. The maximum adsorption capacity of MgO@PO400 for Cu²⁺ was 225.82 mg/g, which was able to exhibit high removal efficiency (84.95–98.05%) for Cu²⁺ in the pH range of 3 to 5.5, and good immunity to the presence of different coexisting ions in the water, demonstrating that potential for treating complex Cu2⁺-containing wastewater. Various characterization methods verified the adsorption mechanism of MgO@PO400 on Cu²⁺, and the results showed that the removal of Cu²⁺ mainly involved ion exchange, surface precipitation and electrostatic attraction. Therefore, MgO@PO400 can be considered a potential adsorbent for removing Cu²⁺ from aqueous solutions.

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Pesticides in soil can migrate to surface water and groundwater. Their behavior and the influence of rainwater on their fate can be studied using ecosystem models, such as microcosms. This study evaluated the impacts of elutriate and leachate from contaminated soil microcosms on the immobility, feeding rate, survival, and reproduction of the Neotropical cladoceran Ceriodaphnia silvestrii. The systems were filled with natural soil and contaminated with 2,4-D and fipronil, both individually and in a mixture, using recommended doses for sugarcane crops. Pesticides were applied once at the beginning of the experiments, and precipitation was simulated twice a week until 21 days of the experiment. Results from the elutriate tests showed a high immobilization for C. silvestrii exposed to fipronil and its binary mixture with 2,4-D, reaching up to 57.5% and 76.25%, respectively. In contrast, acute effects were not observed when organisms were exposed to leachates. Chronic exposure to leachates increased the feeding rates from contaminated treatments. Survival effects were noted solely for 2,4-D, resulting in a 15% reduction, while reproduction decreased in treatments with 2,4-D, fipronil, and their mixture (56%, 42%, and 48%, respectively). These results demonstrate the significant impacts of soil contamination with pesticides on aquatic ecosystems and highlight the importance of evaluating elutriate and leachate in assessing soil ecotoxicity.

Bisphenol A (BPA) is a widely used component in plastics, BPA leaches into food and water, under conditions with pH changes or increased temperatures. This current study focuses on the evaluation BPA induced developmental toxicity in zebrafish embryos. And estimation of mangrove Avicennia marina (AM) and Avicennia officianalis (AO) leaf extracts for their nullifying properties against BPA these embryos. BPA-induced detrimental effects on embryo pigmentation and mortality are concentrations and time-dependent. The lethal concentration 50 (LC50) value for BPA was determined as 12.5 µg/mL. Co-treatment studies with AM and AO extracts alongside BPA did not significantly nullify toxicity; however, AO showed delayed hatching and increased mortality rates compared to AM. The apoptotic assays showed the induction of neurotoxicity and reduced fluorescence in brain cells and nerves in BPA-exposed larvae. However, AM and AO extracts at 25 µg/mL showed significant protective effects in brain cells and spinal regions akin to control. AO demonstrated superior neuroprotective effects, highlighting its potential as a nullifying agent against BPA-induced neurodegeneration. Fungal stains used, showed significant reduction in BPA present in the solution, proving its BPA degrading capabilities. Future studies could explore the molecular mechanisms underlying these effects and optimize concentrations for enhanced nullification of BPA-induced toxicity.

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Microbes are the most sensitive component of soil, and they are affected by any change in the soil properties caused by land use patterns and the application of pesticides. Exposure to antibiotics and pesticides results in the development of tolerant/degrading and antibiotic-resistant soil microbiomes that can flourish antimicrobial resistance (AMR) in other biota. Therefore, analyzing the emergence of AMR in soil due to anthropogenic activities is a prime concern. Due to comprehensiveness, high resolution, and versatility, a whole metagenome (shotgun) based study was conducted for the assessment of wide range of AMR and pollutant degradation pathway genes in rice field soils under the influence of land use (tillage) changes and herbicide (pendimethalin) application. In the zero tillage herbicide treatment versus zero tillage control groups, beta-lactam, vancomycin, and cationic antimicrobial peptides were the most significantly affected AMR genes, with fold change of 1.19, 1.20, and 1.31, respectively. Similarly, the most affected degradation pathways genes were of dioxin degradation, phosphonate/phosphinate metabolism, atrazine degradation, and benzoate degradation with fold change of 4.00, 2.00, 1.75, and 1.18, respectively. Overall, the study reveals an increase in AMR and pollutant degradation ability of soil microbial flora due to tillage and herbicide treatment. Pollutant degradation will aid in restoring soil health and environmental sustainability, whereas addressing AMR signifies the need for adequate monitoring and regulations to mitigate the spread of AMR. Henceforth, the outcomes would contribute in developing sustainable agricultural practices in rice fields to reduce the AMR load and enhance the efficacy of pollutant degradation in soils.

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