International Journal of Environmental Science and Technology最新文献

In-situ water depth measurement is a time-consuming and expensive process for large-scale and frequent monitoring. This underscores the need for alternative methods, such as those based on satellite imagery, which can offer a more efficient and cost-effective solution. This research explores the use of PRISMA hyperspectral images for bathymetry in Nayband Bay, South Iran. The proposed method, SSIP_PSO, includes image pan-sharpening, spectral and spatial information preservation, Particle Swarm Optimization for band ratio selection, and enhanced geometric correction. Among fusion methods tested, the Gram-Schmidt Transform proved most effective for pan-sharpening. The optimal band ratio, b4/b19, improved bathymetry accuracy, reducing root mean square error from 2.291 to 1.716. SSIP_PSO outperformed traditional methods and demonstrated the importance of preserving spatial information in bathymetry.

Chlorination by maintaining the injected chlorine concentration in the range between the minimum and maximum is among the most inexpensive and common disinfection methods in water distribution networks. The minimum concentration of residual chlorine must be observed to control the microbial quality of water. Besides, the maximum chlorine concentration must be observed to control problems related to water smell and taste and to prevent the production of toxic byproducts. This research has developed a model by combining the EPANET model and the ACO_R optimization algorithm to optimize the chlorine injection program during the operation period. According to the results, the ACOR algorithm could be used to derive a suitable program for chlorine injection in the water distribution network such that the permissible constraints of chlorine are observed in the consumption nodes of the network and the consumption of chlorine is reduced to the least level in the network. The developed model was applied to determine an optimal chlorine injection program in a classical example (the Branford network), which was also of interest to some previous researchers. Using the optimal injection program obtained by the model, the chlorine concentration was set at an acceptable network level between the permissible range of 0.2–0.8 g/l. This output was more favorable than the response of other methods in terms of the total residual chlorine concentration, which was 5.8% and 4.7% lower in this method than the methods based on PSO and genetic algorithms, respectively. Moreover, a better convergence speed was obtained in this algorithm, and the number of calculation times of the objective function was 49.5 and 64.4 less than the methods based on PSO and genetic algorithms, respectively. Therefore, the ACO_R algorithm can be used to derive the chlorine injection program to both comply with the permissible constraints of chlorine and reduce chlorine consumption to the minimum level.

This paper utilizes field sampling and laboratory testing to identify potential sources of heavy metals, including rock, dust, rainfall, surface water, and groundwater, employing Pearson Correlation Coefficient—Principal Component—Sources Factors Analysis. A total of 33 surface and 22 profile soil samples were collected to investigate the migration characteristics and spatial distribution of heavy metals in the study area. Additionally, the paper discusses the comparison of soil heavy metal concentrations between sunny and shady slopes. The findings reveal that soil heavy metals in the study area primarily originate from weathering and downward migration deposition of parent rock, indicative of a geological high background area. Moreover, this has led to arsenic contamination in the soil, with an excess rate of 74.5%. It was observed that heavy metals tend to accumulate more on shady slopes than sunny slopes, with mercury and arsenic showing the most significant differences at 69.70% and 49.33% higher levels, respectively. The comprehensive impact index of agricultural soil was calculated at 53.25, indicating a sub-pollution level. Additionally, the study notes that with the increase in crop enrichment coefficient, the variation values of soil heavy metal concentrations decrease, with a correlation coefficient of 0.6077 between the two variables.

Sugarcane is an important crop globally as it is a primary source of sugar and is used in the production of a wide range of products such as food, biofuels, and renewable materials. In Iran, sugarcane is significant as it contributes to the country’s sugar production and supports its agricultural industry, providing employment and economic value to the region. In this study, the physiological changes of sugarcane plants under drought stress were investigated. After callus formation and transfer of the plants to a shoot culture medium, drought stress was applied at four levels: control, 0.4, 0.8, and 1.2 mM/L of polyethylene glycol in the MS culture medium. Changes in morphological characteristics, as well as biochemical properties including pigments, antioxidant enzyme activity, and non-enzymatic antioxidants of sugarcane plants under drought stress, were measured. Drought stress led to a decrease of about 34% in growth parameters and phenolic content increased by 1.43 times of sugarcane plants, proportional to the concentration of polyethylene glycol in the culture medium, while osmolytes and antioxidant enzymes such as catalase, superoxide dismutase, peroxidase, ascorbate peroxidase, glutathione reductase, and glutathione peroxidase, showed higher levels, indicating that one of their roles in sugarcane is responding to drought stress and neutralization of reactive oxygen species. These insights can inform the creation of drought-resistant crop varieties, supporting sustainable agriculture in regions prone to water scarcity. Moreover, they could pave the way for advancements in water conservation practices and help mitigate the impact of climate change on farming.

Several papers have been published in the literature about the effect of surfactants on anaerobic digestion process and results have shown that surfactants had contradictory effect in different concentrations. To understand the reason of this contradictory effect, the surfactant behavior was studied during the anaerobic digestion process in this research. Firstly, laboratory-scale experiments were conducted using 200 cc reactors at mesophilic temperature to determine the optimum inoculum-substrate ratio and several parameters were measured such as chemical oxygen demand, total solids, volatile solids, pH, dissolved oxygen, electrical conductivity, total dissolved solids and alkalinity. Results have shown that optimum inoculum-substrate ratio was four. In the second part of this research, batch experiments were conducted with four Sodium Dodecyl Benzene Sulfonate concentrations namely 0, 100, 200, 400 under mesophilic condition lasted for 50 days. It was observed that a fundamental change in anaerobic digestion occurred at the surfactant concentration of 400 ppm in such a way that surfactant played the role of an obstacle in the anaerobic digestion. To study the effect of surfactant concentration on anaerobic digestion, electrical conductivity and turbidity of tab water and synthetic wastewater were plotted versus surfactant concentration. Results of these graphs showed that electrical conductivity of synthetic wastewater was raised sharply after critical micelle concentration unlike tab water due to the interaction between charged species in synthetic wastewater with formed micelles. In addition, at concentrations higher than 400 ppm, the number of produced micelles increased exponentially in synthetic wastewater. The inhibition of growth rate of microorganism could be attributing to the micelle-forming surfactant which induced curvature stress in cell membranes and led to disordering and then cell lysis.