This study aimed to optimize the integrated exploitation of water resources to reduce the drop in the level of the Hashtgerd aquifer, Iran, based on an integrated management. Firstly, hydroclimatology and groundwater balances were estimated, revealing that the 25-year drop in the aquifer level is 20.32 m. By modeling scenarios of population increase with a five-year growth rate of 3.4% and the construction of two wastewater treatment plants, along with optimizing the supply of demand through integrating the use of resources in the WEAP model, it was determined that in a five-year perspective, discharge from the aquifer to supply the water needs of drinking and industry will increase by 5.70 and 6.58 million cubic meters (MCM), respectively. By treating 11.32 MCM of industrial wastewater for industrial use along with treating 40% of urban wastewater and 57.37 MCM of agricultural wastewater for agricultural use, discharge from the aquifer showed a reduction. The model determined that agricultural needs exhibited the greatest effect on the aquifer level drop. The results showed that implementing the optimized scenario not only prevents the aquifer level drop in the five-year perspective, but also the aquifer balance will increase up to +2.1 MCM.
Urban runoff is one of the main pathways for the transport of microplastics (MPs) to receiving environments. The present study was conducted with the aim of quantifying, investigating the physicochemical characteristics, and identifying the sources of microplastics in the surface water collection network of the Tehran metropolitan area. For this purpose, in order to understand seasonal effects, sampling was carried out at 34 stations during two hydrological periods, namely the wet and dry seasons. After particle extraction based on the standard NOAA protocol, a combination of morphological analysis using scanning electron microscopy (SEM) and polymer identification using spectroscopic techniques (FTIR/Raman) was employed. The findings showed that the average concentration of microplastics in the wet season (598 particles/L) was significantly higher than in the dry season (416 particles/L). In terms of morphology, fragmented particles (fragments), with a frequency of more than 50%, were the dominant form, and the highest particle density was observed in the size range of 1–20 μm. The polymer profile indicated the dominance of polyethylene (PE) and polypropylene (PP) with a frequency of 22.58%. This finding clearly confirms that, in addition to tire wear and environmental degradation of plastic waste, the interference and illegal connections of the sewage network to surface water channels are the main driving force of microplastic pollution in Tehran’s runoff. These findings highlight the urgent need for revising integrated urban infrastructure and developing source-control strategies to protect downstream water resources.
Nanostructured CdS thin films were fabricated on FTO substrates by electrodeposition for the photoelectrochemical detection of Pb (II) ions in water. The CdS films were deposited at an applied potential of 830 mV for 6 min, producing uniform nanostructured coatings on the conductive substrate. The structural, morphological, and compositional characteristics of the films were systematically investigated using X ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X ray spectroscopy (EDS). XRD analysis confirmed the formation of polycrystalline CdS with well-defined diffraction peaks corresponding to the CdS phase. SEM observations revealed a homogeneous nanostructured surface composed of closely packed grains with an average size of approximately 40 nm, providing a high surface area beneficial for sensing applications. EDS spectra verified the presence of Cd and S as the dominant elements, indicating the successful formation of CdS without detectable impurity phases. Optical characterization indicated a band gap energy of approximately 3.3 eV, demonstrating suitable photoactive behavior under visible light illumination. The photoelectrochemical sensing performance of the CdS thin films toward Pb (II) ions was evaluated in the concentration range of 1–20 ppm under periodic illumination (10 s light/dark cycles). The photocurrent response increased linearly with increasing Pb (II) concentration, following the calibration relationship: I(μA) = 0.42C + 0.19 The stronger sensing response is mainly due to the nanostructured CdS surface, which helps separate charges more efficiently and offers more sites for Pb (II) to bind. Overall, electrodeposited CdS films provide a simple, affordable, and effective way to detect Pb (II) in water.
Water pollution has become an increasingly serious threat to human survival and economic development on a global scale. Prevention and control of water pollution, to protect water resources, and adopt the road of sustainable development has become the common goal of mankind. It is an important way to solve the problem of water environment pollution and rational utilization of water resources by correctly mastering and rationally using existing water treatment technology and researching new water treatment technology. This paper reviews the use of wastewater treatment technologies to remove contaminants from wastewater. Many different treatment technologies exist; this study briefly outlines those used most widely in the world. Several conventional wastewater treatment techniques, i.e. chemical coagulation, adsorption, activated sludge, have been applied to remove the pollution, however there are still some limitations, especially that of high operation costs. In the use of wastewater treatment technologies, we must consider the realities and conditions of a region, taking into account criteria such as the complexity of construction of the technology, the type of system operation, the costs of implantation, maintenance and operation. This research work and the conclusions drawn may be utilized for performance assessment of wastewater treatment technologies.
The present study was conducted to determine the effects of source separation training for municipal solid waste on the quality of compostable organic waste at District 8 of Karaj Municipality, Iran. This was an experimental study, the tools of which were sampling and conducting experiments. The research data were collected using cluster sampling. To determine the chemical properties of wet waste, samples were taken from 480 households in 7 neighborhoods of District 8 of Karaj Municipality, followed by laboratory analysis. To measure the quality of compostable organic materials, first, waste from the studied households was received once without providing training and subjected to physical analysis (separation of wet and dry materials). Once again, after providing training, the waste of the studied households was collected separately, wet and dry, from the doorsteps of the homes. From the total wet waste samples taken from each neighborhood, after complete mixing, one sample was taken for chemical analysis and transported to the laboratory. The measured parameters included total nitrate, organic carbon, electrical conductivity (EC), pH, calcium, cadmium, copper, iron, potassium, magnesium, phosphorus and lead. A t-test was used to obtain the difference between the physical and chemical properties of the wet waste before and after source separation training to households. Data were analyzed using SPSS27 software. Based on the results, there was a statistically significant difference between the values of EC, pH, cadmium, and iron at the level of 5%, as well as between the parameters of copper, potassium, magnesium, and phosphorus at the level of 1%, in the pre- and post-training stages. The EC value in the pre-training phase was 9914 μs/cm, which decreased to 7350 μs/cm after training. Calcium levels were 19,674 and 30,898 mg/kg, potassium levels were 24,006 and 18,225 mg/kg, phosphorus levels were 1987 and 3019 mg/kg, and the iron levels were 1804 and 466 before and after training, respectively. The concentration of magnesium in compostable organic waste increased significantly in the post-training phase compared to the pre-training phase. The findings of this study revealed the effectiveness of source separation of municipal solid waste in maintaining the amounts of elements present in compostable organic materials at appropriate levels.
The role of economic factors is significant in the municipal waste management. The present descriptive-applied study aimed to present a new model of municipal waste management cost reduction priorities based on the Gray-TOPSIS model in Ahvaz City in 2022. Following the collection of data on the current municipal waste management, effective criteria influencing cost reduction in municipal waste management were determined through document analysis. Expert analysis was also utilized to identify factors impacting cost reduction in municipal waste management. The Gray-TOPSIS methodology was applied to prioritize solutions for cost reduction in municipal waste management. Through calculating the Kendall agreement index, 20 solutions for cost reduction in waste management were categorized and prioritized into educational, political, cultural, and executive groups. The findings revealed that while political measures such as approving laws related to municipal waste management and incentive and punitive policies with special weightings of 0.804 and 0.799, respectively, are the most effective solutions for reducing waste management costs, overall, educational process-related solutions with an average weighting of 0.686 have a higher priority than other processes. Government support and public education through various means, especially non-governmental media and social networks, are potential solutions for reducing municipal waste management costs in Ahvaz City under current conditions.
In this research, using research-descriptive methods and using data from the years 2012-2022 of meteorology and air pollution in Tabriz city, the correlation of meteorological factors and their effect on the level of air pollution in Tabriz city was investigated and zoning maps were presented. Based on the results of the research, high amounts of CO, NO2, SO2 and O3 pollutants are mostly accumulated in areas 6, 7 and 8 of Tabriz municipality, and these pollutants have different amounts in different seasons and changing the impact of meteorological factors. Investigating the role of climatic elements in the increase of air pollutants in Tabriz city shows the existence of an inverse relationship between pollutants and the increase in altitude and rainfall. The role of wind in the spring and summer seasons leads to an increase in pollutants compared to the wind direction and is almost ineffective in the winter season. As the temperature increases, the amount of carbon monoxide pollutant increases and the amount of sulfur dioxide gas decreases. In general, the examination of the temperature factor shows that the amount of air pollution increases at lower temperatures.
The accumulation of potentially toxic elements (PTEs) in roadside soils and plant leaves due to vehicular emissions presents significant environmental and public health risks, particularly in densely populated urban areas. This study evaluated the concentrations of five PTEs—copper (Cu), lead (Pb), nickel (Ni), cadmium (Cd), and zinc (Zn)—in soils and leaves of three urban plant species (Pine, Cypress, and Mulberry) across six highways in Tehran, Iran, categorized into high, medium, and low-traffic zones. Soil samples were collected at a depth of 0–30 cm, and leaf samples were obtained from the canopy's outer sections. Samples were digested with aqua regia (soil) and nitric-hydrochloric acid (leaves) and analyzed using atomic absorption spectrophotometry. Pollution indices, including Pollution Load Index (PLI), Transfer Factor (TF), and Bioaccumulation Factor (BCF), were applied to assess contamination levels and metal mobility.The results showed moderate pollution levels across high-traffic zones (PLI = 3.94), with cadmium (Cd) contributing the most significant ecological risk (RI = 154.50). Transfer Factor (TF) analysis revealed high bioavailability for zinc (TF = 0.78) and lead (TF = 0.81), while cadmium exhibited limited uptake by plants (TF < 0.004). Bioaccumulation Factor (BCF) calculations indicated Pine and Cypress species had higher potential for metal uptake, with BCF values exceeding 1 for zinc and lead in high-traffic areas, whereas Mulberry demonstrated relatively lower accumulation. Despite a normalized NIPI index value of 1, the enrichment factor (EF) for zinc (EF = 98.04) underscores significant anthropogenic contributions, particularly from non-exhaust vehicular emissions. These findings highlight the need for ongoing monitoring, effective traffic management, and remediation strategies to address heavy metal pollution in urban environments.
This paper, aims to evaluate the impacts of potential climate change on the stream flow of a semi-arid catchment (called Merek) in western Iran using Distributed Catchment Scale Model (DiCaSM) and IHACRES lumped model and compare their ability in simulation of the future stream flow in this area. The joint probability plot was used to generate seasonal climatic change factors (% change in rainfall and change in temperature °C) to apply as an input to the DiCaSM model. A suite of 15 Atmosphere-Ocean Global Circulation Models (AOGCMs) from the Coupled Model Inter-comparison Project (CMIP) with monthly rainfall and temperature data for the baseline period were evaluated. By analyzing the models, finally, the three best models, including GFDL-CM3, CNRM-CM5 and NorESM1-M models, which reproduce the climatic behavior of monthly temperature and precipitation values, were selected. To study the impact of future climatic change on water supply, this study applied the RCP Scenarios. It proved an acceptable performance in reproducing of the historical observations three Representative Concentration Pathways (RCP 2.6, RCP4.5, and RCP8.5) scenarios for the future period 2040-2069. Results indicated that both hydrological models were able to simulate the observed stream flow successfully in the study catchment. The projections of three AOGCMs showed that the future temperature would be increased in the area, while there was no agreement between the models in simulation of future rainfall. Changes in stream flow simulated by DiCaSM model were ranged from -5.2% to 6.2% for the period 2040-2069, while for IHACRES model, the changes ranged from -37.7% to 10.1%. Overally the model performed extremely well for both the calibration and validation years. It is recommended to use these hydrological models for a general evaluation of climate change impact in water resources studies.
This study aimed to identify and prioritize effective methods to increase public education and participation in household waste management in Tehran (capital of Iran) as a pilot city. First, baseline data were gathered through a library research process, and then 33 waste management experts were employed as a panel to complete a researcher-made questionnaire on a Likert scale. Statistical tests and factor analysis were used to analyze the data and determine the relationships between the components. According to the results, among the determined 27 items of identifying and developing educational approaches for public participation in waste management, the item "environmental literacy" ranked first with an average score of 4.52, and the item "individual training" ranked lowest with an average score of 3.91. The final model includes five levels of factors influencing environmental education and promoting public participation. Normed Fit Index (NFI=0.96), Relative Fit Index (RFI=0.96), and Comparative Fit Index (CFI=0.98) indicated that the proposed model had a good fit. The Goodness of Fit Index (GFI=0.91) and the Adjusted Goodness of Fit Index (AGFI=0.89) also confirmed the goodness of fit of the model. Effective municipal waste management requires active participation of citizens, which can be achieved by providing environmental education.
This study aimed to explore the possibility of removing cadmium, a toxic heavy metal, from soil using Dandelion greens. To accomplish this, a greenhouse experiment was conducted with six treatments including a control, and varying concentrations of cadmium in the soil. After the plants were harvested, the concentration of cadmium was measured in the plant roots, the above-ground parts, and soil samples. The results indicated that Dandelion greens have a remarkable ability to absorb cadmium from contaminated soils. The higher the concentration of cadmium in the soil, the greater the amount of cadmium absorbed by the plant roots and the above-ground parts. Specifically, the concentration of cadmium in the above-ground parts increased by 20.4 times and in the roots by 38 times with an increase in cadmium concentration. The average amount of cadmium absorbed in the root and shoot was 69.17 and 59.14 mg/kg, respectively. Furthermore, the study found that the time required for plant purification increased with the increase of cadmium concentration, and the minimum time required for purification was found to be 5 mg/kg concentration. Dandelion greens have a relatively short growth period and high yield, making them a viable option for treating cadmium-contaminated soils. Therefore, Dandelion greens can be utilized as an ornamental plant for phytoremediation of cadmium-contaminated soils. Overall, this study highlights the potential of Dandelion greens as a cost-effective and eco-friendly solution for heavy metal pollution in soil.
The current work aimed to identify factors affecting liability and compensation for marine pollution in Iran. This applied research was conducted using a grounded theory and descriptive-analytical method. Following an in-depth survey and extraction of an initial list, 20 relevant experts selected by a snowball sampling method were interviewed to complete and validate the research process. The research findings revealed 60 open codes and 21 axial codes in a paradigm model. Five components identified as causal conditions included severity of environmental pollution, type of environmental damage, source of pollution, insurer conditions, and nature of the insured. Four components of contextual conditions involved type of environmental risks, level of risk, theoretical foundations, and national and cross-border cooperation. Five intervening factors were national laws and regulations, international environmental law and international treaties, international sanctions and restrictions, governance approach and government policies, and arbitration conditions. Interactional strategies consisted of facilitation, risk management and awareness raising. Consequences were found to be compensation for environmental damage, mechanism to prevent recurrence of similar incidents, and increasing trust and willingness to fulfill environmental commitments. To conclude, stressing and paying attention to international environmental laws can pave the way for environmental insurance activities in the country. Stressing and paying attention to international environmental laws can pave the way for environmental insurance activities in the country.
The exhibition industry serves as a huge platform for face-to-face participation and the formation of potential economic and business relationships in the current century. These gatherings cost greatly in terms of energy resources are responsible for the emission of greenhouse gases and other pollutants into the water, air, and soil. The present study seeks to investigate and identify the pollutant indices resulting from the activities of the exhibition industry, its respective services and preparing guide on the organization of exhibition sites. For this purpose, the most important environmental criteria influenced by the industry were first identified through the Delphi method and were then classified into nine main priority groups based on multi-criteria decision-making and the best/ worst method(BWM[1]) method. The environmental index of the region was thus selected as the most important criterion whereas the social and economic indices were determined to be the least important criteria. Moreover, 58 sub-indices of the main indices were also weighed and prioritized based on the pairwise comparison. As a result, the sub-criterion of environmentally sensitive region ranked first while the sub-criterion of impact on the local and regional identity was identified as the least important influential sub-criterion. Weighing and prioritization of the indices were eventually the main foundation for the compilation of the exhibition site construction and operation instructions, and persistent monitoring of some indices such as the indoor air quality and consumed energy can reduce the negative environmental consequences of exhibition activities significantly.
The aim of this study was to assess the noise pollution of sports facilities in multi-purpose halls in Lahijan city, Iran. This research was of applied type. Through networking, 16 halls were randomly selected in four zones of the city and data were collected in the field. The sound level in the clubs was measured at level A and as an equivalent level by a portable device and Decibel X 2019 and compared with the sound standard (OSHA-90 dBA). The measurements were performed in triplicate and repeated three times. The calculated parameters included sound pressure level (SPL), average sound level ((LP) ̅), continuous sound equivalent level (Leq) and individual daily dose LAEp,d. The results showed that the lowest sound pressure level was 73.9 dB in the northern zone and in the first turn. The highest sound pressure level in the western zone was 97.7 dB. As the time changed from early morning to night, the average sound pressure level increased, highlighting the direct relationship between the sound pressure level and the measurement time. The average sound level in the western zone was higher than in other zones, and the average sound level in the southern zone was lower than in other zones. In both zones, the gyms were of the shed type, which could not establish a relationship between the structural form and the sound level. All the studied halls had levels higher than the standards for recreation centers and parks, as well as the standards of the United States Environmental Protection Agency (EPA). However, all of the gyms met other standards such as ACGIH, NIOSH and OSHA standards related to occupational health. Finally, there was a relationship between the urban location of sports halls and the sound level, such that halls located in the northern and western zones (the more affluent part of the city) had higher sound levels; in contrast, those located in the southern and eastern zones (poorer areas of the city) had lower sound levels.
The purpose of the current work was to develop strategies suitable for the construction waste management for construction waste processing, recycling or landfilling plants in Tehran metropolis, Iran. This integrated methods study was of an applied type with an exploratory approach, which used a FANP-DEMATEL combined model as one of the most appropriate strategic planning methodologies. Thus, the environment of Tehran waste management organization (TWMO) was evaluated by preparing a SWOT matrix consisting of 10 strengths (S), 12 weaknesses (W), 9 opportunities (O), and 7 threats (T). According to the results, the TWMO was positioned in the WT box (IFE: 2.45 and EFE: 2.33), indicating the necessity of adopting a defensive strategy as the best priority. On the other hand, the FANP-DEMATEL technique also confirmed the accuracy of WT strategies with a score of 12.627. Results shown that the best determined WT strategy was “Preventing mixing or separating waste at the source for easier recycling at the plant site" (Weighting factor: 0.9). These findings showed the importance of the proposed strategy for the growth and success of construction and demolition waste management in Tehran.
This study was conducted with the aim of evaluating the dispersion of suspended particles and potentially toxic elements in the air and soil around Shahid Rajaei Thermal Power Plant. For this purpose, soil sampling was carried out in a regular network with a radius of 10 km to measure the concentration of potentially toxic elements, and separately, the distribution model of particles and potentially toxic elements released from the power plant chimney was determined using AERMOD software up to a distance of 25 km. Results showed that the concentration of potentially toxic elements in the soil around the power plant has a direct relationship with the particles coming out of the power plant chimney and their deposition in the soil, and the trend of soil pollution up to a distance of 8 to 10 km from the power plant shows the highest concentration of the studied elements, and with increasing distance from the power plant, Pollution levels are reduced. In the affected areas, the concentrations of vanadium, nickel, zinc, and copper exceeded the standard with values of 237, 88,210 and 112 ppm, respectively, and the four elements cobalt, chromium, molybdenum, and lead with values 21, 115, 4.7 and 42 ppm showed lower levels of pollution. which are also related to the type of fuel consumed by the power plant. Modeling of particle dispersion in the air by AERMOD method with the trend of dispersion and concentration of the above elements is consistent with the analysis of soil pollution.
Land use change shapes landscapes and is crucial for effective natural resource management, requiring a deep understanding of its trends for informed land management. The study utilized Landsat TM and Sentinel-2 satellite images spanning 1994 to 2023 to generate a 30-year land use change map of Erzurum. After processing of satellite images in ENVI, the Maximum Likelihood Algorithm used for classification and the Kappa coefficient used for reliability of results. Single and dynamic land use change indices used to assss the changes in LULC classes. The results indicated appropriate accuracy in the classified maps with a Kappa coefficient exceeding 0.75. The results revealed that the most significant land use changes in the Erzurum region were related to the conversion of rangeland to agricultural land. Over the period from 1994 to 2023, there was a notable increase in agricultural land use in Erzurum, contrasting with negative trends in waterbodies and garden areas. Rangeland experienced the most significant decline, decreasing by 19.22%, while agricultural land increased by 18%. indicating the highest growth among land use categories. According to the Single Dynamic Index, Bare Ground exhibited a change of +0.32%, while tree lands displayed a notably high dynamic degree of +0.31%. The significant expansion of agricultural land in Erzurum is primarily driven by agriculture being the main livelihood for local communities. This shift from rangelands highlights the strain on natural resources, necessitating careful management planning to balance agricultural expansion with environmental conservation concerns.
Identifying the contribution of different land uses plays a crucial role in preventing erosion and prioritizing land management activities. This research aimed to assess the impacts of various land use scenarios on mitigating soil erosion in the North West Urmia region of Iran. In addition to the current scenario, 12 land use management scenarios were identified based on the observed trend in changes in land use patterns throughout the study area utilizing GIS. The RUSLE was used, and the necessary input parameters of the RUSLE model, were prepared. The erosion mapping has been done using overlaying the input layers. The baseline scenario (current condition) resulted in an erosion amount of 17.22 (t/ha/yr). Introducing soil conservation techniques in dry farming on steep terrain, as depicted in scenario 6 (conservation and restoration of plowed rangelands), resulted in a reduction of the erosion rate from 17.22 to 9.75 (t/ha/yr). On the other hand, scenario 20, characterized by severe rangeland degradation and overgrazing, exhibited the highest estimated erosion rate at 30.42 (t/ha/yr). In contrast, the most substantial erosion reduction of 43.37% was evident in scenario 6 (conservation and restoration of plowed rangelands). It was observed that the P-factor (support practice factor) had a more pronounced impact than the C-factor (crop/vegetation and management factor) in mitigating erosion. These findings suggest the potential for utilizing a scenario-based framework to evaluate the impact of management scenarios on erosion and prioritize soil and water management measures and strategies.
The use of copper (Cu) and silver (Ag) nanoparticles in coatings can eliminate surface microbial contamination. This study compared antibacterial activity of Cu- (Cu/CNTs) and Ag-coated carbon nanotubes (Ag/CNTs) synthesized by plasma-enhanced chemical vapor deposition (PECVD) against Escherichia coli and Staphylococcus aureus. Initially, the PECVD technique was applied to deposit the CNTs on high-resistivity silicon wafers previously decorated by nickel catalyst using an Electron Beam Gun. Then, the nanotubes were coated by Cu and Ag thin films in a vacuum evaporator using the Direct Current (DC) Magnetron Sputtering method. Finally, the antibacterial effects were determined by Standard Plate Count (SPC, with film thicknesses of 0, 10, 30 and 60 nm) and Disk Diffusion Test (based on zone of inhibition (ZOI) with nanoparticle concentrations of 5, 10 and 15 µg/mL). According to the SPC findings, the highest antibacterial activity of Cu/CNTs was found for the film thickness of 60 nm against E. coli (66%), and the lowest activity was related to the film thickness of 19 nm against S. aureus (28.8%). The antibacterial activity of Ag/CNTs was about 70% against E. coli with the highest thickness and about 34.12% against S. aureus. The lowest ZOI was measured for the bare CNTs at a concentration of 5 µg/mL (12 mm), and the highest ZOI was related to Ag/CNTs with a concentration of 15 µg/mL against S. aureus (18 mm). To conclude, the carbon nanotube composites coated with copper or silver nanoparticles can be used to control bacterial growth in aqueous solutions.
Abstract: Hazardous waste is generated by numerous industrial, commercial, agricultural and even domestic sources. The dangers of these wastes can vary depending on their types and environmental conditions and various short-term and long-term effects ranging from acute to chronic are expected. This study was carried out in regard to health and economic considerations and to create motivation for conducting studies to identify industrial hazardous waste which plays an important role in growing trend of country's industry. In this research, we selected 51 important industrial units of Ardebil province and data were collected through questionnaires, in-person interviews with the unitsâ authorities and referring to available documents. The information contained the types and amount of waste, temporary storage method, Discharge frequency, final disposal method, and the status of recycling and reuse. The results obtained from data analysis without considering uncontrolled industrial wastewater, show the annual production of Approximate 2,010,265 tons of waste; which about 1502 tons of this amount (according to available list in the Basel Convention), has classified under the title hazardous waste and about 12.42% of this type of waste was toxic. The share of liquid and solid physical states of the waste is respectively 59.87%, 13.77%. It should be noted that there is no temporary storage for about 20.29% of this waste. Reviewing the final disposal method indicates that about 28.66% of hazardous waste is discharged into the environment without any control.
