International Journal of Environmental Science and Technology最新文献

The use of water productivity indicators for management of water resources is considered in different regions of the world. This research was conducted with the aim of using virtual water and physical and economic productivity indices of water for major agricultural crops to optimize water consumption. The research was conducted for 26 farms in Kurdistan, Iran with three different climates. Reference crop evapotranspiration and effective precipitation were calculated using CROPWAT software. The amount of water consumption was calculated by separating green and blue water and compared with field measurements in the 2017 crop year. To calculate physical productivity and economic productivity, the crop water productivity (CWP) index and the benefit per drop (BPD) and net benefit per drop (NBPD) indices, respectively, were used. The results showed that sugarbeet and barley have the highest and lowest CWP with 4.55 and 0.43 kg/m³, respectively. The measured water consumption in most farms is larger than the calculated values. According to the CWP index, the priority of crop cultivation is sugarbeet, potato, cucumber, apple, alfalfa, wheat and barley. However, BPD and NBPD indicators showed that the priority of cultivation is apple, cucumber, potato, sugarbeet, alfalfa and wheat respectively. The results of the NBPD index showed that apple and barley have the highest and lowest water economic productivity with 54,000 and 2000 IRR/m³, respectively. The findings, elucidating the significance of employing water economic indicators as opposed to water consumption metrics, can serve as a valuable reference for agricultural practices in analogous climatic regions globally.

One of the current challenges confronting the microbial fuel cell (MFC) is the unstable organic substrate for microbial species, which results in poor electron generation. This work utilized the rotten rice as an organic substrate in the MFC to promote microbial species activity, eliminate the organic pollutant formaldehyde, and increase power generation capacity. Only a few research used rice waste as an organic substrate in MFC, and they were solely applicable to hazardous metal removal. The study was conducted in a single-chambered MFC over a 30-day period. The voltage generation of the MFC was monitored daily, while formaldehyde removal was monitored at regular intervals. After the operation, the electrodes were biologically examined to determine the influence of the microbial species. The bioremediation efficiency of formaldehyde was 71% which was achieved in 30 operational days. The maximum voltage from the system was recorded on day 20 and was found to be 394 mV. This study presented the reaction process of rotten rice oxidation in the cell. Furthermore, the formaldehyde removal and electron generation degradation mechanisms are detailed. The study suggests that the rotten rice is a suitable organic substrate for the microbial species in MFC.

Tropical forests are prone to fires, and the severity of burns modulates a crucial function in evaluating the influence of fires on soils. Yet, information about the consequences of wildfires on soil geochemical attributes, carbon stocks, and microbial biomass carbon is limited in Ghana. Therefore, this study was conducted to elucidate the short-term dynamic of soil physico-chemical properties, carbon stocks and microbial biomass carbon to varying fire burn and identify and map sensitive soil quality indicators affected by wildfires in Ghana’s Tain II Forest Reserve. Forty (40) soils were sampled from a 0–15 cm mineral horizon under four forest fire classes (unburnt, low-burnt, moderate-burnt, and high-burnt) in the Tain II Forest Reserve in the 2023 dry season. Concentrations of macronutrients, soil organic matter, total organic carbon, and carbon stocks were higher in the low burn than in the unburnt, moderate, and high burn. Soil microbial biomass carbon was significantly higher in the unburnt (19.88 Mg C kg⁻¹) than in the low burn (16.43 Mg C kg⁻¹), moderate burn (13.90 Mg C kg⁻¹) and high burn (9.88 Mg C kg⁻¹) areas. From the PCA, ten (10) soil sensitive quality indicators to wildfires, including organic carbon, total organic carbon, organic matter, microbial biomass carbon, microbial biomass quotient, clay, available phosphorus, exchangeable calcium, magnesium, and aluminium. Thus, the consequences of wildfires on quality indicators in the Tain II FR are demonstrated and could serve as a database for forest soil quality management after wildfires in the tropical climate of Ghana.

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Nowadays, the intensification of the production of biodiesel from non-edible oil crops is mandatory to overcome petrol-fuel depletion and environmental pollution. For the first time, enhanced biodiesel production from castor oil via rotor–stator hydrodynamic cavitation has been studied in this work. Response surface methodology based on one-factor-at-a-time design of experiments was employed for modelling and optimizing the biodiesel yield and the decrease in feedstock viscosity, density, and total acid number (TAN). The predicted optimum parameters of 8.15:1 methanol:oil (M:O), 1499 rpm, 29.38 min, 48.43 °C, and a KOH catalyst concentration of 0.74 wt.% resulted in a 96% biodiesel yield with a concomitant decrease in viscosity, density, and TAN of approximately 95%, 5.12%, and 90.02%, respectively. According to the results of the breakthrough kinetic calculations, the reaction is pseudo-second order, with the activation energy, frequency factor, and reaction rate constant being 0.23 M⁻¹ min⁻¹, 18.77 kJ/mol, and 6.32 M⁻¹ min⁻¹, respectively. The fuel properties of the produced biodiesel and bio-petro-diesel blends were good, comparable to international standards and the marketed Egyptian petro-diesel.

In recent years, the dyes discharged from various textile industries have been the main concern of water contamination. With increasing water scarcity problems, it is necessary to synthesize a low-cost, effective visible-light-driven photocatalyst for organic pollutant degradation. In the present study, g-C₃N₄/GO/CuFe₂O₄ (CGC) nanocomposite was fabricated successfully through an in situ hydrothermal method to degrade the methylene blue (MB) dye as a model pollutant. The as-synthesized nanocomposites were analyzed by FTIR, XRD, XPS, SEM/EDX, Zeta potential, and UV–Vis spectroscopy. The photocatalytic activity of the novel ternary CGC composite was assessed under sunlight illumination. The impact of numerous photodegradation parameters like pH, photocatalyst dose, H₂O₂ amount, initial dye concentration (IDC), and contact time were examined. Ternary CGC exhibited higher degradation efficacy at an optimum value of pH (6), H₂O₂ amount (8 mM), photocatalyst dose (20 mg/100 mL), and IDC (10 ppm) leading to 99% MB degradation within 60 min. The CGC composite exhibited extraordinary photocatalytic performance as compared with those of g-C₃N₄/CuFe₂O₄ (CC) and GO/CuFe₂O₄ (GC) composites. It can be explained by the fact that CuFe₂O₄ coupled with g-C₃N₄ and GO results in the effective separation of photoinduced electron–hole pair which causes improved photodegradation efficacy. Furthermore, CGC composite displayed outstanding reusability and is easier to recover after degradation process, which is pertinent to practical application.

Evaluating the Sea surface temperature (SST) pattern of the Persian Gulf is considered as a key parameter in understanding global climate changes. The present study aims to examine and compare the above-mentioned changes in the Asian continent and other oceans in the world. The correlation of the aforementioned parameter with the volume of warm water in temperature of more than 20 °C was compared considering the El Niño Southern Oscillation (ENSO) phase during 36 years. The remote sensing temperature data in 24 selected points in the Persian Gulf and Strait of Hormuz were collected from the NOAA site in terms of years and same months, and processed. Based on the results, no significant relationship was reported by the Pearson correlation coefficient of 41.66% between the volume of warm water and temperature during 36 years. No significant relationship was defined in the seasonal approach and same months. A significant relationship was observed by the average correlation coefficient between the two quantities after breaking the time period to six years. The maximum variance values of the above-mentioned index have been accompanied by a weaker intensity of 1.5–2 years similar to the Persian Gulf since 2000. Furthermore, the curve regression calculation indicated a significant relationship between temperature extremes and the aforementioned index. As observed, the intensity of the fluctuations and maximum extreme in the variance dereases significantly. An uneven event occurs at the minimum limit during 2010. Further, the maximum event occurs within 1–2 years. The intensity of the fluctuations related to temperature dispersion in the surface of the Persian Gulf increased during 1980–2000 compared to 2000 and later similar to the variance related to the volume of warm water entering the Indian Ocean. A significant relationship was reported in the averages of the same months between the extremes and aforementioned index in all of the 11 types of curve regression. Finally, the best adaptation equation was extracted.

The cactus cochineal, Dactylopius opuntiae (Cockerell, 1929) (Cockerell) (HEMIPTERA: DACTYLOPIIDAE), has continued to expand throughout Morocco since its introduction in 2014, which has resulted in causing severe damage to various Opuntia prickly pear species. The present study provides biological management methods of this insect pest by evaluating the insecticidal effect of Nicotiana glauca Graham and Ricinus communis Linnaeus extracts. The different extraction methods (methanolic, decoction, and maceration) and a positive control D-limonene were used on adult females and nymphs of D. opuntiae. All plant extracts had insecticidal effects and were dependent on concentration and post-treatment evaluation timing. For D-limonene, 100% cactus cochineal mortality was achieved at a concentration of 8%, 24 h post-treatment. The decocted extracts of N. glauca and R. communis and the cold macerated extract of R. communis at a 4% concentration had a mortality rate of up to 70%, 120 h post-treatment. The other three plant extracts (N. glauca/methanol, N. glauca/cold maceration, and R. comminus/methanol) also induced insecticidal activity approaching 70% mortality 120 h post-treatment at a concentration of 8%. Moreover, results of the phytochemical analysis of these extracts indicated high amounts of carotenoids and coumarins. Polyphenol contents ranged from 22.88 ± 0.39 to 68.42 ± 0.50 µg gallic acid equivalent/ mg dried extract, while flavonoid contents ranged from 22.62 ± 5.87 to 131.02 ± 1.46 µg quercetin equivalent/mg dried extract. The lethal dose (LD50) of these extracts reveals that D-limonene was the most toxic with an LD50 = 1019.92 ppm followed by the cold macerated extract of N. glauca with an LD50 = 5860.91 ppm.

Herein, the effectiveness of different amounts of highly active bimetallic FeMn catalysts (5, 10, and 20 Si/bimetal mole %) for water contaminant elimination was elucidated. The catalysts were immobilized on cage-like SBA-16 supports using the impregnation method. The Fe:Mn ratio was kept constant at 1:1 for all the catalysts. To characterize the synthesized catalysts, N₂ adsorption–desorption analysis was performed in order to study the structure of the catalysts. XRD was used to examine the crystal structure, while SEM, EDS, and mapping techniques were employed to investigate the morphology and distribution of the bimetal on the support. To evaluate the activity of the catalysts in removing water contaminants, three different dyes, namely Methyl Orange (MO), Orange (II) (O(II)), and Methylene Blue (MB), were selected. The influence of the amount of bimetal loaded on the support, catalyst dosage, H₂O₂ concentration, and pH variation was investigated on the dye removal process in order to find the best operational condition for efficient dye degradation. Based on the experimental data, the catalyst with 5% FeMn on SBA-16 was determined to be the most effective catalyst with 87% degradation of MO, 99.8% of O(II), and 99.9% of MB using a catalyst dosage of 0.5 g/L, an H₂O₂ concentration of 0.98 mM, and a pH of 4. Overall, this research highlights the synthesis and characterization of bimetallic FeMn codoped SBA-16 catalyst, and their effectiveness in removing water contaminants, as demonstrated by the degradation of various dyes under specific operational conditions.