环境•农林最新文献

The mass production and widespread use of pharmaceuticals and personal care products (PPCPs) posed a great threat to the water environment and human health. In this paper, a green plant-based Bi-Zr bimetallic MOF SU-101.2 was prepared, and the adsorption characteristics were studied with typical PPCPs-Diclofenac sodium (DCF). Compared to SU-101 and SU-102, SU-101.2 showed a significant increase in the adsorption rate of DCF. The adsorption mechanisms between SU-101.2 and DCF were mainly electrostatic interactions, hydrogen bonding and π-π interactions. Moreover, SU-101.2 also had considerable photocatalytic properties, which was applied to the subsequent treatment of adsorbent desorption, effectively solving the problem of secondary pollution and achieving a green sustainable adsorption and degradation cycle. In all, this work presented an effective adsorbent and a sustainable approach for DCF elimination, which could replace traditional chemical desorption and regenerate the adsorbent via a photocatalytic process.

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This study assessed pollution levels, ecological and health risks, and spatial distribution of eight heavy metals in sediments of Wadi El-Gemal Island, south Marsa Alam, Red Sea, Egypt. The analyzed metals (mg/kg) followed a decreasing order: Fe ˃ Mn ˃ Zn ˃ Co ˃ Pb > Ni ˃ Cu > Cd. Principle component analysis (PCA) of the investigated metals showed significant loadings of Mn, Ni, Fe (geogenic source) and Cd, Pb, and Zn (anthropogenic source). Twelve ecological, sediment quality guidelines (SQGs), and health risk indices were applied. Enrichment factor (EF) values in sediments showed low (Cu), minimal (Ni), moderate (Pb, Mn, and Zn), and significant enrichment (Cd and Co), while contamination factor (CF) showed low contaminated sediments (CF <1). Geo-accumulation index (I_geo) showed uncontaminated (Cd), moderately to strongly contaminated (Pb, Cu, Ni), strongly contaminated (Co), and extremely contaminated sediments (Fe, Mn, Zn). Pollution load index (PLI) and degree of contamination (DC) indicated low contamination, whereas Nemerow pollution index (NPI) showed unpolluted sediments (NPI ≤1). Potential ecological risk index (PERI) indicated low risk (PERI <150). The SQGs mean effects range median quotient (MERMQ) indicated low-priority risk level of toxicity (MERMQ ≤0.1), and toxic risk index (TRI) showed low toxic risk in the island’s sediments (TRI <5). Hazard index (HI) levels for all metals indicated low chronic non-carcinogenic risks (HI <1). Total cancer risk (TCR) levels of Cd, Pb, and Ni were below U.S. EPA permissible limit (1×10⁻⁴), while Cd had the highest TCR levels for children and adults.

Cadmium (Cd) contamination of soils is a major agricultural and environmental concern. Biochar (BC) is well known for enhancing crop production, while incorporating lignin (LN) with BC for decreasing Cd uptake and availability has not been studied. Herein, we investigated the effects of LN+BC under different irrigation regimes on Cd uptake, soil properties, and maize growth in Cd-contaminated soil. We used three irrigation regimens as main treatments: 60%, 80%, and 100% of evapotranspiration (ET₀). Sub-treatments were soil amendments consisting of 5% BC, 5% LN+BC, and control (CK). Results showed that 60% and 80% irrigation regimens increased Cd concentrations in plant parts while LN+BC application decreased Cd uptake. However, LN+BC and BC significantly decreased Cd uptake across all irrigation regimes. The combination of LN+BC was found to be more efficient in reducing Cd uptake. The order of Cd concentration in plant tissues was as follows: CK > BC > LN+BC. LN+BC significantly increased relative leaf water content (LRWC), membrane stability index (MSI), all growth indicators, and yield attributes compared to CK. Among organic amendments, LN+BC improved grain quality by increasing starch grains, decreasing protein matrix, enhancing side scattered (SSC), and forward scattered (FSC) light signals, followed by BC and CK. The incorporation of LN+BC boosted soil pH, cation exchange capacity (CEC), and organic matter (OM). Combining BC and LN can minimize Cd phytoavailability, enhance soil quality, and boost crop growth in contaminated agricultural soils. This study suggests that a combination of LN and BC can be added as an organic amendment in Cd-contaminated soil.

Wetlands act as filters, retaining phosphorus (P). The objective of this study was to evaluate the degree of P lability of hydromorphic (Histosol) and non-hydromorphic (Cambisol) soils under natural condition (no P addition) and with mineral P addition. The mineral P added was equivalent to 100% of the maximum phosphorus adsorption capacity, incubated during 0 and 120 days, at depths of 0-10 and 40-60 cm. The sequential P extraction was: labile, moderately labile, low lability, and residual. Under the natural condition, the moderate and low lability fractions were predominant in the Histosol, indicating lower P lability compared to the Cambisol. Total phosphorus (Pt) and organic phosphorus (Po) were higher in the Histosol compared to the Cambisol. After 120 days incubation with mineral P, the labile fraction decreased and the moderately labile fraction increased in the Histosol, demonstrating the effect of time on P stability. The addition of mineral P increased inorganic P (Pi) and also Po in both soils, indicating a strong interaction of mineral P with soil organic matter. The Po extracted with NaOH 0.1 mol L^-1 (moderately labile) was predominant in both soils and it was higher in the Histosol when compared to the Cambisol. In general, under both conditions (natural and mineral P addition), the Histosol stored P in more stable forms, reinforcing the need for permanent preservation of wetlands.

With ongoing insect declines, species expanding in distribution and abundance deserve attention, as understanding their success may help design conservation strategies for less successful species. Common causes of these successes include warmer climates, novel resources, and exploiting land use change, including land abandonment. These factors affect the nymphalid butterfly Neptis rivularis, developing on Spiraea spp. shrubs and reaching the north-western limits of its trans-Palearctic distribution in Central Europe. We combined mark-recapture, behaviour analysis, and distribution modelling to study N. rivularis in wetlands of the Třeboňsko Protected Landscape (IUCN category V). The long-living adults (up to 4 weeks) spent a considerable amount of time searching for partners, ovipositing and nectaring at Spiraea shrubs, alternating this with stays in tree crowns, where they located cool shelters, spent nights, and presumably fed on honeydew. They formed high-density populations (310 adults/ha), exploiting high host plant abundance. They adhered to floodplains and to conditions of relatively mild winters. The ongoing Spiraea encroachment of abandoned alluvial grasslands is, thus, a transient situation, ultimately followed by forest encroachment. Rewilding the habitats by introducing native ungulates presents an opportunity to restore the disturbance regime of the sites. The increased resource supply combined with a warming climate has opened up temperate Europe to colonization by N. rivularis.

As a kind of emerging contaminant, microplastics (MPs) widely exist in environments around the world and may carry other chemical pollutants. Besides, radioactive pollutants in water are getting more and more attention due to the discharge of wastewater from the Fukushima nuclear power plant. Among them, Uranium is an important fuel substance in nuclear power plants, which has toxicity of radioactivity and heavy metals. In order to research the interaction between MPs and uranium in water, batch experiments were conducted to study the adsorption behavior of radioactive heavy metal uranium (U(VI)) by ordinary PET MPs. The results showed that the adsorption amount of U(VI) onto PET increased (69.02%) after aging. The kinetic adsorption behavior of U(VI) could be explained by pseudo-second-order and Elovich models, and the isothermal adsorption behavior of U(VI) was well fitted by Langmuir and Sips models. The adsorption amounts were in the order of aged PET > virgin PET and ultrapure water > simulated freshwater. Besides, external diffusion and internal diffusion were included in the adsorption process. The adsorption capacity was affected by pH and salinity. The adsorption mechanisms included pore filling, electrostatic interaction, and surface complexation. The properties of MPs and the environment are the main factors affecting the adsorption process. The study elucidates the adsorption mechanism of U(VI) onto MPs in ultrapure water and simulated freshwater, aiming to assess the potential risk to aquatic environments where natural MPs and uranium ions coexist.

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Applying conventional antiscalants, e.g., polyphosphates, may bring about environmental and health concerns, warranting the application of green compounds. This work reports the application of amino acids such as glutamic acid and glycine, individually and in the presence of sodium tripolyphosphate (STPP) and sodium hexametaphosphate (SHMP), as antiscalants. At various dosages, these inhibitors were added to calcium sulfate supersaturated solutions, and the inhibition values were determined at 71 °C for 24 h, according to a standard jar test method. Moreover, in the jar environment, the changes in electrical conductivity and turbidity, and size and bulk volume of the deposit particles were measured and used to unveil the affected stages of scaling and the governing mechanisms. Statistical analyses revealed that some amino acid-containing inhibitors used at commercially acceptable dosages, 2 and 4 ppm, effectively inhibited the scale formation by approximately 90%, comparable to pure polyphosphates (p < 0.05). These mixtures also provided up to 70% reduction in the consumption of pure polyphosphates. Consequently, drawbacks associated with polyphosphates are mitigated, and the risk of biofouling linked to applying green molecules at high dosages is minimized. Furthermore, the amino acids and polyphosphates synergistically inhibited one or multiple stage(s) of scale formation. Notably, ion association in the prenucleation stage, and nucleation were selectively and remarkably prevented in the presence of 2 ppm glycine/STPP and 4 ppm glycine/SHMP, respectively. These findings hold great promise for developing sustainable, safe, and efficient inhibitors for various processes such as membrane-based water purification.

Cactus cladodes have been emerged as one of the most popular plant-based flocculants. They have been listed as a promising natural alternative to the noxious synthetic flocculants. However, practical application of this bio-flocculant is still hampered by some questions concerning their formulations’ stability, active agents therein and their flocculating performance. Thus, in this study, three cactus formulations, namely, cactus juice (CJ), cactus lyophilized powder (CLP) and oven-dried powder (CDP) were subjected to a physicochemical characterization to provide an in-depth understanding of the main flocculation active agents and distinguish the suitable preparation method promoting bio-flocculants’ stability and effectiveness. Therefore, their flocculating activity was evaluated in treating a model-colored effluent, a crystal violet (CV) dye solution. The obtained results show that the three cactus formulations exhibit a significant sugars content with considerable calcium amounts. The highest sugars content was registered for CLP thanks to the efficacy of lyophilization method to maintain their stability. Furthermore, the main flocculating active compound was identified as an arabinogalactan composed of long polygalacturonic acid chain backbones with branches of neutral sugar residues involving mostly the arabinose. As for the color removal performance, an outstanding CV removal exceeding 99% was found using CLP under alkaline pH. It was occurred through charge neutralization and bridging mechanisms. Hence, based on these groundbreaking results, the application of cactus formulation-based flocculants, especially the lyophilized one is highly recommended to ensure a clean, eco-friendly and sustainable wastewater treatment approach.

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