Original Article
Rogahyeh Shokri Biarargh; Marjan Nematimehr
Abstract
Introduction: So far, the use of water sensitive urban design (WSUD) has not been investigated in cities of Iran. This issue, for the first time introduced in Australia in 1994, has been implemented in several countries, such as America, Germany, the Netherlands, and Australia. The main objective of ...
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Introduction: So far, the use of water sensitive urban design (WSUD) has not been investigated in cities of Iran. This issue, for the first time introduced in Australia in 1994, has been implemented in several countries, such as America, Germany, the Netherlands, and Australia. The main objective of WSUD is to establish a link between urban planning and design, and landscape design with sustainable management of water flows in a city. In other words, this approach tries to revitalize the natural water cycle in the city by presenting urban design-oriented solutions that may have less environmental damages. Material and methods: In this descriptive-qualitative research, the WSUD approach has been firstly addressed; then, its indicators, as integrated water management factors, have been extracted, evaluated, and analyzed in the rainy city of Rasht. In addition, based on findings of the study, some strategies for improving the water management in the city of Rasht have been proposed. Since the extraction of its dimensions and indicators depends on an accurate and exact investigation of the resources and documents, data collection was done by a documentary study. In order to infer the repeatability and validity of the extracted data from the documentary texts, the content analysis was used. The extent of the significance of indicators is not the same. Therefore, after extracting dimensions, components and repeated indicators of integrated water management, the coefficients of the significance of each level at a higher level, based on obtained data from content analysis, have been calculated by data from the experts’ questionnaire (Delphi) which is 5-point Likert scale method. At last, the significance of each indicator was determined. Results and discussion: Based on the findings obtained from experts’ questionnaire, the environmental indicator was the most significant factor in sustainable urban water management, as well as urban river health and rate of rainwater storage with weights of 0.0469 and 0.0463, respectively. To analyze the present situation in Rasht city, observation, questionnaire, and statistical databases in the form of Swat Table were utilized as the instrumentation. By weighting the internal and external factors, based on the GOSP matrix, appropriate strategies were introduced in the group of adaptive strategies. In addition, prioritization was done by QSPM matrix strategies on different levels. Ultimately, appropriate policies for applying the water-sensitive urban design approach were made in Rasht city. The outcomes of these strategies can be as follows: transformation of the gray infrastructure network of the city of Rasht into the green-blue infrastructure network, eco-revelatory of green infrastructures instead of underground pipelines, changing attitudes towards the links of water, nature and buildings, and increasing citizens’ awareness of the natural water cycle, preventing urban flooding in passages during rainfall, cleaning up the rivers of Zarjoob and Goharrood as well as wetlands of Rasht and making them the green corridors and major leisure spots, increasing green roofs, green walls and green terraces that have positive effects on the city’s temperature, air quality, wildlife, and mental health, and reducing drinking water consumption for non-drinking consumptions up to 50 percent (i.e., reduction of five million liters of drinking water only by collecting and handling gray water or rainwater and utilizing it as for rainwater flush tanks of buildings), etc. Conclusion: The WSUD approach, as the latest urban design approach for sustainable urban water management, has been developed for the management of surface runoff quality to a wider framework, i.e., for integrating urban water management in combination with urban design. It is noteworthy that it testifies that there is a possibility of managing surface waters in the city, in such a way that, in spite of existing more than 2000 mm rainfall per year, and even the flow of 200 mm on height over the passageways, the use of urban spaces is not disturbed.
Original Article
Ahmadreza Farzaneh; Maryam Mirabi; Mahdi Jalili Ghazizade; Maryam Abbasi
Abstract
Introduction: Pars Special Economic Energy Zone in Asaluyeh has several petrochemical units. These units produce a significant amount of different types of wastes) hazardous and non-hazardous (annually. Spent molecular sieve and catalyst wastes are the most important waste produced in petrochemical complexes. ...
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Introduction: Pars Special Economic Energy Zone in Asaluyeh has several petrochemical units. These units produce a significant amount of different types of wastes) hazardous and non-hazardous (annually. Spent molecular sieve and catalyst wastes are the most important waste produced in petrochemical complexes. Based on available statistics, in the next 25 years, annually an average of 3000 tons of spent molecular sieve and 2000 tons of catalyst waste will be produced in these areas. Because of the necessity of optimal management of industrial wastes, the primary objective of this study was to identify and classify these two types of waste products and then, to investigate the ability to recover these wastes and in particular the feasibility of using them in the manufacture of concrete. Material and methods: First, identification and classification of these two wastes was done using elemental analysis experiments, measurements of heavy metals and determination of organic compounds and compare them with the EPA toxicity standard. In order to assess the feasibility of using these two types of waste in the manufacture of concrete, concrete samples were made based on concrete mixing plan, which includes ways of replacing these two wastes with cement. The 7-day compressive strength measurement of the concrete and leakage toxicity analysis (TCLP) were also done in order to assess the feasibility of recycling these wastes from a technical and environmental point of view. Results and discussion: Both residues had two major combinations of Silicon dioxide (SiO2) and Aluminium oxide (Al2O3), which makes it possible to replace them with the cement in concrete. Based on the analysis of heavy metals, due to the significant amounts of Chromium (Cr) element in the spent molecular sieve (about 11ppm), this waste can be classified into industrial hazardous waste categories. Also, the analysis of organic compounds showed that the amounts of all organic compounds in these two types of waste are less than the standard amounts for hazardous waste. The results of the 7-day compressive strength measurement of the spent molecular sieve showed that using this waste in the manufacture of concrete improves the initial bonding of concrete, and this is due to the significant amounts of Al2O3 in this waste. So, replacing 10% of this waste can be considered as an optimal amount to increase the initial bonding of the concrete. However, the catalyst waste did not have a positive effect on the primary fix of the concrete. Finally, the TCLP analysis showed that the concretes made with these two wastes are classified as non-hazardous materials, which is due to the stabilizing properties of concrete. Conclusion: The preliminary study of spent molecular sieve and catalyst waste characteristics indicates that using these two types of waste in concrete production is feasible from a technical and environmental point of view. Therefore, we suggest that further tests need to be done.
Original Article
ٍEsmaeil Asadi; Fatemeh Bayat
Abstract
Introduction: Today, we observe a decline in groundwater quality due to the factors such as population growth, industrial expansion, and agricultural development and so on. Considering that human health is affected by the quality of groundwater, conservation of the quality of groundwater is very important ...
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Introduction: Today, we observe a decline in groundwater quality due to the factors such as population growth, industrial expansion, and agricultural development and so on. Considering that human health is affected by the quality of groundwater, conservation of the quality of groundwater is very important in water resources management. Therefore, many quality indicators such as Water Quality Index (WQI) have been developed all around the world to determine the water quality of a region. The purpose of this study was to determine the parameters affecting on water quality in Zanjan Plain using entropy theory and main components analysis, determining susceptible points of contamination and finally, ranking the areas in terms of quality of drinking water with the combination of Topsis method and EWQI index. Material and methods: This study was conducted in Zanjan Plain with an average rainfall of 323 mm per year and a maximum temperature of 40 °C and a minimum temperature of -29 °C. The parameters that are studied in order to determine the groundwater quality of Zanjan Plain were sulfate, chloride, bicarbonate, acidity, total dissolved solids, sodium adsorption ratio, electrical conductivity, potassium, sodium, magnesium, calcium, and total hardness. Principal Component Analysis (PCA) was used to determine the main components of the water quality in the area. Then, using the EWQI index, the results of this method were explained. The water quality index is defined as a scoring method for investigating the combined effects of the independent parameters on the total water quality. In order to prevent the expert judgments, the weight of each parameter in calculating the water quality index was determined using the entropy method. Ultimately, the ranking of areas in terms of water quality was applied using the combination of the TOPSIS method and the EWQI. TOPSIS method as a multi-criteria decision-making method is a simple and efficient method for prioritization. Results and discussion: According to the statistical characteristics of the quality parameters, the electrical conductivity and total hardness were higher than the WHO standards, which can be attributed to the geological structure, the presence of calcareous layers, and many evaporate sediments in the plains. The results showed that chloride was the most effective parameter on the groundwater quality in Zanjan Plain. Investigating the groundwater quality changes in Zanjan Plain during 2003-2016 showed that the wells of Koushkan and the suburbs of Zanjan were determined as potentially contaminated points, and the degradation factors of the groundwater quality in these areas were determined chloride (Cl) and sodium adsorption ratio (SAR), respectively. According to the results of the analysis method of the principle components and the diagram of Scree Kettel, total hardness parameter (TH) and Cl were most effective on the water quality of Zanjan Plain, respectively. More than 80 percent of the groundwater quality changes in Zanjan Plain can be evaluated with three factors. The first factor was the most responsible with more than 57 percent of the change. Then the second factor with more than 12 percent of variation and the third factor with 9 percent of the changes were the most important factors affecting the quality of groundwater of Zanjan Plain. In order to prioritize the Zanjan Plain in terms of groundwater quality, the combination of TOPSIS method and EWQI index was used. According to the results of this method, Yengijeh station was selected as the best station with excellent quality and Koushkan station was selected as the worst station with undesirable quality. Conclusion: Chloride parameter with low entropy and high entropy weight was the most effective parameter in the plain. Also, Yengijeh and Koushkan stations were selected as the best and worst stations, respectively.
Original Article
Mohammad Mohammadian; Gholam Reza Lashkaripour; Naser Hafezi Moghadas Hafezi Moghadas; Mohammad Ghafoori
Abstract
Introduction: At present, the increase in the Earth's population has led to an increase in consumption, and an abnormal harvest of water and soil resources.MaydavoodPlain is a very fertile plain with rich water resources in the east of Khuzestan Province.In recent years, water contamination and sinkholehazards ...
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Introduction: At present, the increase in the Earth's population has led to an increase in consumption, and an abnormal harvest of water and soil resources.MaydavoodPlain is a very fertile plain with rich water resources in the east of Khuzestan Province.In recent years, water contamination and sinkholehazards have happened in this plain.To date, very few environmental studies have been carried out on this plain. Material and methods: In this study, field and laboratory studies have been used to study the environmental hazards of the Maydavood Plain. During field studies, many sinkholes around the Maydavood Plain were identified and their dimensions were measured. Samples were collectedfrom the rocks and water resources of the region. The solubility test was carried outon gypsum samplesof Gachsaran Formationusing the circulation method. By using the Geographic Information System (GIS), isopotential map of sulfate and calcium ions was prepared for the plain. The ICP-OES analysis was used to determine the amount of heavy metals in water.GISwas also used toprepare theisopotential map ofheavy metals in the Maydavood Plain. Results and discussion: According to the office studies, the MaydavoodPlain is surrounded by Asmariand Gachsaran Formation and the bedrock of this plain is Gachsaran Formation that consists of gypsum and marlstones.All of thesinkholes are formed near the Gachsaran Formation. Results of the solubility test showed that gypsums had high solubility. Base on the isopotential map of sulfate and calcium ions, the amount of these ions were more concentrated around Sarelah and Dogacheh villages than other parts of the plain due to the dissolution of Gachsaran Formation gypsum. Hydrological studies showed that during the last 15 years, the groundwater level of the Maydavood Plain has decreasedabout 5 meters. In recent years, a few sudden sinkholes were formed, especially around Sarelah and Dogacheh villages due to the high solubility of Gachsaran Formation gypsum and a decrease in groundwater level. The type of these sinkholes a is cover collapse. Hydrochemical analysis of groundwater showed that 81, 31, 44, and 100 % of deep wellshad concentrations greater than permissible valuesof arsenic, iron, manganese,and nickel, respectively.Also, concentrations of vanadium in all of the deep wells were lower than the permissible value. Base on heavy metals isopotential map, the amount of heavy metals around of South MaydavoodPlain (Sufla) and MaydavoodVasati villages were higher than other parts of the plain. The source of heavy metals in the plain was the petroleum material pollution from oil spring existing. Conclusion: By controlling the excessive pumping of groundwater and using artificial nourishment, it is possible to prevent the decrease of groundwater quality and the formation of new sinkholes in the plain. Otherwise, the new sinkhole may be formed and cause damage. High concentrations of heavy metals in groundwater can be hazardous for the health of people living in this region. To avoid this hazard, it is suggestedto providethe drinking water for the MaydavoodPlain’s populationfrom another area with a permissible value ofheavy metals.
Original Article
Hossein Moradi Zinab; Ahmadreza Mehrabian; Siavash Naghizadeh; Hossein Mostafavi; Farzaneh Khajoi Nasab
Abstract
Introduction: With increasing rates of biodiversity loss in recent years, new conservation methods have emerged. For example, by identify areas with unique endemic species and the habitat of species with special values (e.g., medicinal or endangered species) or areas that are highly threatened, ...
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Introduction: With increasing rates of biodiversity loss in recent years, new conservation methods have emerged. For example, by identify areas with unique endemic species and the habitat of species with special values (e.g., medicinal or endangered species) or areas that are highly threatened, we can provide the most protection at a lower cost. In Iran, there are taxa that have conservation priority due to their high diversity and threats. The genus Onosma L. is classified as one of these priorities in Iran due to the ecological and medicinal importance and being the center of speciation and biodiversity. It is necessary to determine the patterns of distribution, endemism and conservation status of these species. Material and methods: In this research, using a database prepared from previous field studies and herbarium data, geographical distribution points of the species in a georeference geomorphology map of Iran were made to grid cells with ArcGIS software with a resolution of 25 × 25 (20 × 20 km) UTM and then the diversity zones have been determined. Then, based on the variety of geomorphologic-climatic conditions, various stations were selected for evaluation. Field studies were performed at these stations based on elevation gradient. At each station, the quadrates were established based on the type of habitat and population characteristics of the species. At each station, between three and five quadrates were set up and in each quadrate the coverage, density, diversity and surface coverage of the target species were evaluated. Within each quadrate, three to five individuals were sampled. Then, from each quadrate, the soil samples were collected from the surface to the depth that the root is deployed. In addition, habitat features such as habitat physiognomy, threats, and other ecological features were noted. In addition, the collected samples were fixed and stored according to standard protocols. The identification of taxa was done based on Iranian flora, Iranica and flora of Iraq, Flora of Turkey, and the former Soviet Union. Assessing the threatened species was performed according to the Red List of Regional Guidelines for the Conservation Union, assessing the conservation status of the habitats was done in accordance with the guidelines of the World Conservation Union and the rare species were classified based on a combination of standard methods. Results and discussion: In this study, the distribution patterns of nine species with 106 populations of Onosma was assessed using a geobotanical approach. Among the studied specimens, one species belonged to the subsect. Asterotricha., two species belonged to the subsect. Heterotricha., and six species belonged to the subsect. Haplotricha All in all, only four species were endemic of Iran. The elevation range of the studied species was 455 to 2950 AMSL, and species often occupy mountainous (1500 to 2500 meters) and mountain (900 to 1500 meters) habitats, which are in agreement with the results of previous studies. Most of the populations were distributed in mild, semi-sloping, southern slopes, and semi-humid, Mediterranean and semi-arid climates. The habitats with the average annual temperature of 0-10 °C, average annual rainfall of 200 to 500 mm, low soil depth and sedimentary, igneous, and volcanic-sedimentary geological structures had the most species richness. The species within this genus had the most species richness in the geographical coordinates of 37 to 38 °N latitude and 47 to 48 °E longitude, and the overall richness of species to the north shows a relative and gradual decrease. Also, O. sabalanica was the most threatened and O. microcarpa and O. elwendica were the least threatened, and O. sabalanica and O. subsericea are among the rare species of this genus in the region. Conclusion: Rare species of Onosma often have small populations and are spread only in a limited geographic area and altitudes, which makes them vulnerable to threats. So, along with methods for protecting its species in the natural habitat, species-centric conservation and focusing on ex-situ conservation methods are also recommended.
Original Article
Sara Saidi; Hamid Reza Nasei; Yaser Nik Peyman
Abstract
Introduction: Environmental pollution, especially the increasing trend of water resources pollution caused by oil spills, is one of the main concerns of advanced human societies. Considering the dangerous nature of oil contamination for the environment as well as the development of various diseases such ...
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Introduction: Environmental pollution, especially the increasing trend of water resources pollution caused by oil spills, is one of the main concerns of advanced human societies. Considering the dangerous nature of oil contamination for the environment as well as the development of various diseases such as pulmonary and skin diseases and cancer, it is very important to purify the environment. Material and methods: In the study area, Shahr-e-Ray industrial zone, south of Tehran, petroleum activities have led to aquifer pollution, so that in some parts the thickness of light non-aqueous phase liquid (LNAPL) on the surface of the groundwater reaches more than 20 meters. Since the LNAPL acts as a source of exceeding pollution in the groundwater, in both saturated and unsaturated areas, it is necessary to purify the aquifer, which contains LNAPL fluid. In this regard, awareness of hydrodynamic parameters of the aquifer such as transmissivity and hydraulic conductivity is of great importance and even determinative of the type of recovery methods. Results and discussion: Because of the hydrogeological conditions of Rey industrial zone, LNAPL thickness and also time limitations, the Baildown test was used to determine hydrodynamic parameters of the aquifer, including transmissivity and hydraulic conductivity. This method involves removing the entire LNAPL from the casing and filter pack by moving part of the volume to create head differences. Afterwards, the fluid level is measured during removal. Conclusion: Regarding the results of the Baildown test, the range of LNAPL transmissivities in the aquifer varied between 0.085 to 11.506 m2/day and the range of hydraulic conductivities varied 0.01 to 1.62 m/day. According to the Baildown test result, the highest transmissivity of LNAPL in 10 wells was observed in the eastern and northeastern regions of the study area.
Original Article
Reza Akhbari; Mehdi Nejati
Abstract
Introduction: Attention to the economic consequences of environmental degradation and analyzing the environmental impacts of economic developments, in form of the environmental Kuznets curve (EKC), has been established before the global consensus on the necessity of reducing carbon emissions. The pollution ...
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Introduction: Attention to the economic consequences of environmental degradation and analyzing the environmental impacts of economic developments, in form of the environmental Kuznets curve (EKC), has been established before the global consensus on the necessity of reducing carbon emissions. The pollution haven hypothesis (PHH) also follows the capital transfer from developed economies to developing ones and the analyzing of consequences of its environmental impacts. Recently, the impact of corruption on carbon emissions has been raised as the main objective of empirical studies on the environmental economy. Several attempts have been made, in which assumptions of the EKC and PHH are explained with the help of theoretical foundations on the impact of corruption on environmental quality. In this context, it is argued that based on the PHH hypothesis, corruption, with the weakening of regulatory and monitoring institutions, led to environmental degradation by reducing carbon emission costs and, consequently, the entry of dirty industries from developed countries to developing countries and less developed to follow. On the other hand, corruption, according to EKC, by distorting the income distribution system and undermining productive economic activities, delays the maximum per capita of the gross domestic product, after which the downward trend of carbon emission is begun, resulting in the increased environmental degradation. Recently, a theoretical discussion has taken place about the significant impact of reducing the level of corruption on improving the environmental quality in developing countries rather than in developed ones. It is claimed that in developing and less developed economies, the decline in the level of corruption has more significant effects on reducing carbon emissions. The purpose of this study is to empirically investigate this claim. Material and methods: In this study, we have empirically investigated this claim using panel data including 61 countries during 2003-2016 and the method of threshold panel model in STATA. We analyzed the coefficient of the effect of corruption on carbon emissions via the Human Development Index as a threshold variable for dividing countries into developed and developing. In this framework, at first, using the relevant tests, the thresholds were identified and then based on that, the model including variables like carbon emission, per capita gross domestic product, human development index, urban population growth, primary energy consumption, commodity trade, and corruption index was estimated. Results and discussion: The coefficient for developing countries was estimated negative, significant and larger than developed countries. On the other hand, the coefficient for the developed countries was positive, smaller and not significant. In developing countries, per every unit increase in the index of corruption (which means reducing the level of corruption), the carbon emission will be reduced by 0.08 units, while in developed countries, the effectiveness of carbon emission from corruption has been stopped. The reduction of corruption in these countries does not have a significant effect on the reduction of carbon emissions. Conclusion: As it was mentioned, corruption was a common issue in both developed and developing countries, but comparatively, it had a greater effect on CO2 emissions in developing countries than that in developed ones.
Original Article
Mohammad Taghi Feyzbakhsh; Nasibe Rezvantalab; Parisa Alizadeh
Abstract
Introduction: In recent years, energy consumption in agriculture has increased dramatically, and modern agriculture has become very scarce in energy. Most of the energy used to produce agricultural products is due to the use of inputs such as machinery, fossil fuels, fertilizers and pesticides, that ...
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Introduction: In recent years, energy consumption in agriculture has increased dramatically, and modern agriculture has become very scarce in energy. Most of the energy used to produce agricultural products is due to the use of inputs such as machinery, fossil fuels, fertilizers and pesticides, that inappropriate use of these inputs while reducing energy efficiency in production also causes problems for human health and the environment. At the moment, due to the energy crisis in the world, it is necessary to study more about energy consumption and find solutions for its optimal use (Darlington, 1997). This study was conducted to identify the energy evolution and global warming potential in wheat and barley production in northern lands of Gorgan plain and in the city of Aq-Qala. So that appropriate strategies can be identified to prevent energy wasting and reduce the environmental impact of resources. Material and methods: For this study 95 and 83 farmers were selected for wheat and barley production in Aq-Qala city, respectively. The data including (machines, seeds, fertilizers, fuel and pesticides) were collected by questionnaire. Then fuel, input and output energy, energy evaluation indices and global warming potential (kg CO2.ha-1) were calculated by related coefficients (Soltani et al., 2013). Results and discussion: The results showed that the highest direct input energy in wheat and barley production belonged to fuel consumption were 38.8% and 46.8% respectively. Also, the highest indirect input energy was obtained with 31.3 and 19.1 percent for nitrogen fertilizer for wheat and barley fields, respectively. The ratio of the energy output to the input for rainfed wheat and rainfed barley were calculated 5.01 and 5.03, respectively. Also, global warming potential in wheat and barley production was 943.9 and 739.1 (kg eq-CO2 ha-1), respectively. In another study, greenhouse gas emissions for wheat production in Golestan province were estimated about 1200 kg CO2.ha-1 (Rezvantalab et al., 2015). Also, the results showed that increased fuel and fertilizer consumption will increase the amount of input energy in both crop production and increase the production of greenhouse gases. Therefore, the use of more efficient machinery and equipment, which reduces fuel consumption, and also, considering proper crop rotation and using organic fertilizers can reduce energy consumption, increase energy efficiency and reduce the global warming potential of rainfed wheat and rainfed barley production. Conclusion: The results showed that the fuel consumed in both products had the highest input energy input, followed by fertilizer, especially nitrogen fertilizer, Therefore, the reduction of fuel consumption by using combinators and the use of protection culture systems (minimum tillage) is recommended to reduce the amount. It is also recommended to observe crop rotation and rotation with cover crops that are able to stabilize nitrogen as one of the ways to reduce fertilizer use. It is suggested that yield increase by improving management operations, optimum use of fertilizers, pest control, and then, will improve energy efficiency.
Original Article
Toktam Shahriari; Abdolreza Karbasi; Milad Reihani
Abstract
Introduction: Oil refinery is one of the industrial centers and its wastewater has a lot of environmental pollutants which are a serious threat to the environment and water resources. In this study, an electrocoagulation reactor was used to remove and reduce the amount of Chemical Oxygen Demand (COD) ...
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Introduction: Oil refinery is one of the industrial centers and its wastewater has a lot of environmental pollutants which are a serious threat to the environment and water resources. In this study, an electrocoagulation reactor was used to remove and reduce the amount of Chemical Oxygen Demand (COD) in the wastewater from the API unit of the Shazand Oil Refinery in Arak, which is a gravity separator of water and oil. Material and methods: In order to simulate the electrocoagulation process in experimental conditions, a 15 × 14 × 13 cm Plexiglas pilot was designed, in which six 10 × 12 cm aluminum electrodes with a thickness of 2 mm were put as sacrificial electrodes during the process. The distance between the electrodes was 2 cm. The monopolar arrangement was selected for electrodes. At each stage of the experiment, after measuring the pH and COD of the initial wastewater, the volume of 2 L was poured out as an internal sample into the coagulation reactor; after the electrochemical process, the secondary pH and COD were measured to determine the effect of the electrocoagulation process. Results and discussion: In this research, the effect of time, pH, and voltage in the electro-flocculation process has been evaluated. The amount of COD, pH, and lead were measured 450 mg/L, 5.5 and 5.27 mg/L in initial wastewater, respectively. To avoid the overlapping effect of time, pH, and voltage during the process, the value of one of the parameters was changed and two other parameters were kept constant and the optimum value was determined. In order to minimize the errors during the testing process, each step has been repeated three times. After performing different stages of the test and collecting and analyzing the results, the optimum time of the test, optimum pH, and optimum voltage were considered as 90 min, 6 and 30 V, respectively. Consequently, the COD decreased from 450 to 193 mg/L and 99.05% of lead was removed. The results of the experiments showed that by increasing the duration of electrolysis, the removal rate also increases. The results of other research also showed that the flow density is directly related to the reaction time, and by increasing the time, more removal rate can be obtained. As the results demonstrate, the removal rate is directly related to the applied voltage, which is due to the more production of aluminum hydroxides in the wastewater, which plays the role of coagulant. In previous studies, the results also indicated an increase in the removal rate of pollutants by increasing the applied voltage. The pH also had an important effect on the results. At low pH values, cationic monomeric species such as Al3+ and Al(OH)2+ were obtained from the dissolution of the aluminum anode. On the other hand, with the excessive increase in the pH of the solution, such compounds as Al(OH)4- were formed, which caused disruption and sluggishness in the removal process. Conclusion: The results of this study showed that aluminum hydroxides as coagulants, which are produced by the electrochemical dissolution of the sacrificial electrodes, play a major role in the pollutant removal process. The higher their production rates, the more removal will occur. To do this, the optimal parameters for producing them should be optimally set. By increasing the electrolysis time, the amount of aluminum hydroxides also increases. Also, adjusting the pH of the solution at an appropriate range provides optimum conditions for the production and formation of gelatin aluminum hydroxide polymer.
Original Article
Masoud Motamedi; Azita Behbahaninia; Forugh Farsad
Abstract
Introduction: One of the major contaminants of surface water resources are heavy metals. Heavy metals are natural components of the earth's crust, but human activities, and geochemistry and biochemical cycles may disturb their balance and release them into the environment. Release of pollutants into ...
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Introduction: One of the major contaminants of surface water resources are heavy metals. Heavy metals are natural components of the earth's crust, but human activities, and geochemistry and biochemical cycles may disturb their balance and release them into the environment. Release of pollutants into the aquatic environment will affect both water body and sediments, mostly sediments because they are less dynamic. Therefore, the concentration of heavy metals in river bed sediments reveals the pollution more intensity or its history far better than the water body. This research was carried out to determine the concentration of heavy metals in water and sediments of Shahrud River with the aim of determining the condition of heavy metal contamination and their sources in the study area. Material and methods: The Shahrud River is one of the main branches of the Sefid-Rud River which originates from the central Alborz Mountains, and is the only river in the southern part of the Alborz, which flows into the Caspian Sea. In this study, the concentration of heavy metals namely lead, cadmium, and arsenic in the Shahrud River and sediments in Lowshan city has been studied. Accordingly, the physiochemical properties of water and sediments were investigated in the first stage of sampling. Moreover, five sampling stations were determined and four sampling stages (autumn and winter 1395- spring and summer 1396) were carried out. Totally, 40 samples of water and sediments were taken along the river and the concentration of the considered parameters was measured. Results and discussion: The results demonstrated that COD was lower that the EPA standard in all sampling stations except station 5. Furthermore, regarding the IRWQI (SC) water quality index, all stations were ranked from average to bad classes of quality. The BOD in all sampling stations was higher than the EPA standard and according to the IRWQI (SC) index, all stations were ranked "semi-bad" to "bad" class of quality. The concentrations of lead, cadmium, and arsenic in water samples were compared with the guidelines of the Iranian National Standards Organization, Department of Environment, WHO and EPA. Moreover, it was ranked based on IRWQI (ST). Our results proved that the mean concentration of lead at all stations was lower than the standard except stations 3 and 4. The concentration of these heavy metals was relatively ranked into moderate to good classes. The average concentration of cadmium was lower than the standard at all stations except stations 1 and 3, and in regard to the descriptive index, it is categorized into good to fairly bad, respectively. In addition, the average concentration of arsenic was lower than the standard values at all stations. Also, it was classified as good, regarding the descriptive index. The concentration of heavy metals in sediment samples at sampling stations showed that the concentration of lead at all stations was lower than TEL values in NOAA and SQGs standards, and the concentration of cadmium at all stations was higher than the PEL values. The concentration of arsenic at all sampling stations was lower than the PEL values and at stations 2 and 5 was higher than TEL values. To quantitatively assess the sediments, contamination factors (Cf), degree of contamination (mCd), molar accumulation index (Igeo) and ecological risk assessment (Ri) were considered. Results showed high manmade contamination of cadmium and significant ecological risk in sediments of the study area. The use of phosphorus fertilizers in fields and gardens as well as the location of the cement factory, which is near the river, are the main causes of cadmium pollution in the study area. Additionally, the high levels of BOD and COD in water indicated high levels of organic contaminants, due to industrial and traditional olive processing centers, olive oil mills and poultry slaughterhouses in the study area. Conclusion: The study area was contaminated with heavy metals, which is mainly caused by the high concentration of cadmium in sediments of Shahrud River. It is essential to mention that its negative impact on humans, organisms and urban environment in Lowshan city and downstream of the Shahrud river is undeniable.
Original Article
Bahman Zamani Kebrabadi; Syed Mohammad Hojati; Farhad Rejali; Masoud Esmaeili Sharif; Hamid Reza Rahmani
Abstract
Introduction: Phytoremediation was introduced as an effective, inexpensive and environmentally friendly to remove, displace or disable pollutants from polluted soils. There are numerous physical and chemical methods for the treatment of heavy metal contaminated soils, which in addition to high costs, ...
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Introduction: Phytoremediation was introduced as an effective, inexpensive and environmentally friendly to remove, displace or disable pollutants from polluted soils. There are numerous physical and chemical methods for the treatment of heavy metal contaminated soils, which in addition to high costs, lead to the destruction of the physical and chemical structure and vital activities of the soil. This study was applied in order to investigate the effects of inoculated Arbuscular mycorrhizal fungi of resilience to lead and zinc on some morphological traits (colonization, diameter growth, shoot dry and fresh weight, root dry and fresh weight, height and leaf area) of Elaeagnus angustifolia L. Material and methods: One-year-old seedlings of E. angustifolia species with an average height of 70-50 cm, minimum diameter of 1-1.5 cm and leaf number of at least 30 were provided from Jebel Amelian nursery affiliated to the Natural Resources Office of Isfahan Province. The seedlings were transferred to the greenhouse of the Agricultural and Natural Resources Research Center of Isfahan Province and were kept there for 20 days to adapt to the new conditions. In doing so, six treatments of mycorrhizal fungi (Glomus versifome, G. etunicatum, G. intraradices, G. mossea, composition and control treatments) and five treatments of soil (naturally polluted soil, soil polluted with lead, soil polluted with zinc, soil polluted with lead and zinc, control (without pollution) treatment) were considered. Results and discussion: The results showed that there was a significant difference between the measured variables among the different treatment of mycorrhizal fungi. The highest and lowest colonization were observed for G. mossea (40.5%) and control treatment (25.6%), respectively. For G. mossea, the diameter growth (2.8mm), height (36.1cm) and leaf area index (28.8) increased in comparison to the control treatment. There was a significant difference between shoot dry and fresh weight and root dry and fresh weight in all of the treatment of mycorrhizal fungi. The highest dry and fresh weight of shoot was observed in G. mossea treatment (108.4 and 55 g) and the lowest was observed in control treatment (59.4 and 30.3 g). The highest and lowest of fresh weight were observed in control (95.3) and polluted soil with lead and zinc treatments (78g). Highest values of measured variables in all fungi and soil treatments were belonged to the inoculated treatment of G. mossea and the control treatment, respectively. Conclusion: Results of this study showed that inoculated treatment with G. mossea fungi and control treatment of soil caused the growth enhancement in E. angustifolia. However, there was no significant difference between mean fresh and dry weight of root and leaf area index in different soil treatments. Roots, as absorbent levels of water and food, have great effects on the absorption of water and various salts, and various environmental factors influence the growth of the plant through its effect on root growth. Heavy metal stress is one of the factors limiting root growth which affects plant growth activity. Also, in plants that were inoculated with mycorrhizal fungi, the mean of all measured variables was significantly higher than the control treatment. The highest shoot weight was observed in G. mosseae treatment, which suggests that G. mosseae contributed to the plant's absorption of water and food, especially phosphorus, and increased the accumulation of dry matter and has more efficiency in the biomass production of E. angustifolia.
Original Articles
Roya Karami Darabkhani; Seyed Yusef Hejazi; Abdolmotaleb Rezaei
Abstract
Introduction: Today, as environmental problems are escalating with the ever-increasing rise in population, there is an urgent need to protect the environment. Researchers have suggested various solutions for environmental problems, most of which are technological but nowadays due to the high cost of ...
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Introduction: Today, as environmental problems are escalating with the ever-increasing rise in population, there is an urgent need to protect the environment. Researchers have suggested various solutions for environmental problems, most of which are technological but nowadays due to the high cost of these projects, they are interested in changing people's lifestyles and behavior. They believes the solution for environmental issues should be searched in the change of human behavior and attitude. In this regard the media has a big role to play in making people aware of environment issues and taking actions to protect the environment. media are known as very influential tools for widening and creating awareness, attitude and behavior about environmental issues. Media includig social media apps, websites, TV& radio, print media, etc play an important role in informing and engaging citizens in environmental issues. The great potential of the media in regard to the provision of information, the construction of knowledge and the cultivation of skills and attitudes, has been proved scientifically over the years. One of the important issues about environmental behavior and environmental conservation, is pay attention to environmental Non-governmental organizationseducation and training. Environmental education is a process that allows individuals to explore environmental issues, engage in problem solving, and take action to improve the environment. The main components of environmental education are: Awareness, sensitivity, Knowledge, Attitudes, Skills, intention, Participation and behavior. NGOs, according to their mission and goals, has appropriate facilities to increase public awareness through education and training of their members and other people and should support these organizations in order to achieving their goals.The main goal of this study is to investigating the role of media on some environmental education components including: knowledge, attitude, intention and environmental behavior of environmental NGOs members. Material and methods: The statistical population consisted of environmental NGOs members in Tehran Province. Sample size determined 148 person by using Krejcie and Morgan table and Sampling was done randomly. The main instrument for collecting data was questionnaire which its reliability Obtained based on Cronbach's alpha α=%89. Results and discussion: The results of structural modeling based on partial least squares method shows a significant and positive relationship between the four components (media, knowledge, attitude and intention) with environmental behavior. The results showed that all four variables (media, environmental knowledge, environmental attitude and environmental intention), have a high mean in the environmental NGOs members in Tehran Province. The independent variable (environmental attitude), has the greatest effect on the mediator variable (environmental intention) and also the greatest impact on the dependent variable (environmental behavior), and then media is the most effective variable. Environmental intention as mediator variable 57.1 percent of the variance of the environmental behavior between environmental NGOs members in Tehran Province. Also 34.3 percent of the variance of the environmental behavior is explained by media, environmental knowledge, environmental attitude and environmental intention between environmental NGOs members in Tehran Province. Conclusion: Environmental attitude has been identified as the most effective variable on environmental intention and environmental behavior in this study and Media has been identified as the second most effective variable on environmental intention and environmental behavior in this study. Media’s role in order to increasing environmental knowledge and attitudes of the population is undeniable. Media should be used more to facilitate the transmission of environmental information and promote more positive environmental attitudes. In recent years internet and social networks are the main sources for environmental information. Since digital media are used widely by young people, new educational material should be created in order to meet the updated needs for information concerning environmental issues. So Different programs should be planned by NGOs in order to sharing environmental information through media especially internet and social networks.
Original Articles
Hadi Veisi; Anahita Valiollahi; Abdol Majid Mahdavi Damghani; Surror Khoramdel
Abstract
Introduction: Since the emission of greenhouse gases (GHGs) has changed the chemical composition of the atmosphere, a wide global consensus has emerged on the anthropogenic accumulation of GHGs in the atmosphere. Women have a vital role in agriculture, but the gap in gender-based studies on the ...
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Introduction: Since the emission of greenhouse gases (GHGs) has changed the chemical composition of the atmosphere, a wide global consensus has emerged on the anthropogenic accumulation of GHGs in the atmosphere. Women have a vital role in agriculture, but the gap in gender-based studies on the significant effects of agriculture on carbon emissions through production has not yet been filled. Therefore, a detailed analysis of how the gender factor affects GHGs emission is essential. In this sense, the present study investigated the effect of farmers' gender on global warming potential (GWP) in rice production systems during 2014-2015 in Babol County in Mazandaran Province, Iran. To this end, GHG emissions from male- and female-head rice farms were compared using the carbon input (kg.C.equivalent.ha−1) and output (kg.C.equivalent.ha−1), sustainability indices, and carbon efficiency. Material and methods: The data was gathered from 120 rice farmers (60 males and 60 females) through questionnaires and face-to-face interviews. The methodology of the Intergovernmental Panel on Climate Change was used to calculate the GHGs emission of each farm. Each GHG such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) has GWP, which is the warming influence relative to that of carbon dioxide. Emissions were measured in terms of a reference gas, CO2 and reported based on CO2 equivalent. The method was restricted to a farm boundary and extracted into spreadsheets, which compute the baseline CH4 and N2O emissions for each farm. The indices of sustainability were estimated by assessing the temporary changes in output/input or (output-input)/input ratios of C to determine the share of anthropogenic GHGs emission in the atmosphere to determine the intensity of energy flow, carbon savings, and GHG emissions from women-headed and men-headed rice farms. Results and discussion: The results demonstrated considerable differences between farms headed by women and headed by men in terms of GWP (2930.31 and 3291.35 kg.CO2.equivalent.ha-1 for female-headed and male-headed farms, respectively) since more agricultural inputs were employed in farms headed by men. The dominant share of GWP for farms headed by men and women from the highest to the lowest was due to fossil fuels, machinery, and N fertilizers. The indices of carbon efficiency and carbon sustainability were respectively 3.88 and 2.88 in farms headed by women, and 3.55 and 2.55 in farms headed by men. Conclusion: The largest proportion of GHGs emission was due to fossil fuels in both female-headed and male-headed farms. This was attributed to outdated diesel pumps, excessive machinery traffic in agroecosystems, incompatibility between the power and performance of the equipment with the requirements of female-headed farms, and the relatively low price of fossil fuels. In line with these results, it can be concluded that resource-use patterns for the establishment, production, harvesting, and transportation in the rice fields are compatible with landscapes and masculine norms. Females, like males, used machinery and tools that consumed large amounts of fossil fuels; however, female-headed farms were smaller and wasted more energy, which in turn increased the level of mitigation. The findings suggested that farms by women produced fewer GHGs because the carbon input was used in a more environment-friendly manner than in the male-headed farms. Finally, several “soft” policies, such as gender-sensitive capacity development programs, are proposed to address the share of farmers in the emission of GHGs from subsistence farming systems on a gender basis.
Original Articles
Zohreh Khorasanian; Naghmeh Mobarghaee Dinan; Saeed Soufizadeh; Reihaneh Rasoolzadeh
Abstract
Introduction: Population growth, traffic jam, and industrial development generate air pollution in metropolises such as Tehran. Regarding the fact that air pollution can cause serious damage to the health of citizens, various studies have been conducted at the national and international levels. Undoubtedly, ...
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Introduction: Population growth, traffic jam, and industrial development generate air pollution in metropolises such as Tehran. Regarding the fact that air pollution can cause serious damage to the health of citizens, various studies have been conducted at the national and international levels. Undoubtedly, one of the most important ways to reduce environmental pollution is the use of control programs and measures. Therefore, this study aims to evaluate the effectiveness of some plans and programs to reduce the air pollution of a metropolis (Tehran). Material and methods: To determine the annual fluctuations in air pollutants (Carbon Monoxide (CO), Particulate Matter of 10 microns in diameter or smaller (PM10), Ozone (O3), Sulfur Oxides (SOX), Nitrogen Dioxide (NO2), and Nitrogen Monoxide (NO)), the concentration of these parameters was investigated in Tehran from 2005 to 2012. Pearson correlation analysis and stepwise regression (SAS software) were used to evaluate the relationships between air pollution, number of vehicles and fuel consumption in Tehran. Results and discussion: From 2005 to 2012, the trend of annual changes in CO concentration was decreased. The highest concentration of this pollutant (2006) was 5 mg/l and the lowest concentration (2011) was about 2 mg/l. During the same period, the annual trend of PM10 increased from 100 to140 μg/m3. In these years, the annual trend of ozone decreased from 0.03 mg/l to 0.02 mg/l. Meanwhile, the annual concentration of sulfur dioxide decreased from 0.055 to 0.03 mg/l. Changes in annual NO2 and NO concentration decreased during the mentioned years from l0.07 to 0.2 mg/l and from 0.05 to 0.010 mg/l, respectively. Conclusion: Results show that the trend of annual change in the concentration of pollutants was decreasing for all pollutants (except for suspended particles) from 2005 to 2012. Eliminating eroded cars, and using hybrid and gas-fueled vehicles played an important role in reducing air pollution in Tehran. Also, due to the results of the correlation analysis and the significance of the effect of eroded cars on atmospheric pollutants, the impact of this policy on reducing emissions was significant. The results of stepwise regression analysis from 2005 to 2012 showed that eliminating the eroded cars and replacing them with dual-fuel ones had the most significant effect on reducing carbon monoxide emissions in Tehran.
Original Articles
Fatemeh Effati; Javad Bayat; Maryam Rouhi Kerigh; Masoume Mollaei
Abstract
Introduction: In recent years, urban development, population growth, and increasing human activities created many problems in the aquatic resources in urban areas. Awareness of the quality of water has great importance due to the increasing need for drinking water in the metropolitan cities. In this ...
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Introduction: In recent years, urban development, population growth, and increasing human activities created many problems in the aquatic resources in urban areas. Awareness of the quality of water has great importance due to the increasing need for drinking water in the metropolitan cities. In this study water quality variables were examined to determine the quality of grounwater and the risk of toxic and conventional pollutants in terms of human consumption. Material and methods: For this purpose, a number of nine wells were selected to investigate the groundwater quality in ward 10 of the municipality of Tehran in the years 2014 and 2016, in the summer and winter. The physical variables including temperature, color, turbidity, and salinity and chemical variables including dissolved oxygen (DO), pH, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), nitrite (NO2-), nitrate (NO3-), ammonium (NH4+), total phosphorus (TP), total nitrogen (TN), sodium (Na), calcium (Ca), magnesium (Mg), copper (Cu), iron (Fe), lead (Pb), cobalt (Co), zinc (Zn), and detergent as well as microbial variables were measured. Results and discussion: The results showed that due to the presence of coliform bacteria and high levels of NO3-, the groundwater was polluted by human or animal wastewaters, but there was no serious problem, and it was possible to improve the water quality by processes such as chlorine disinfection. Among the physical variables, only the turbidity was almost twice the standard level in some wells. The Analyses of heavy metals showed that the concentrations of Pb, Zn, Fe, and Cu in the groundwater were extremely high, being several times higher than the reported standard level. Changes in TP were very high and reported up to 0.21 mg. Although total coliform and fecal coliform were low, they violated the EPA standard for drinking water. The presence of these two variables in the groundwater is an indication of the penetration of human or animal wastes into the groundwater and, if used, it will cause harmful effects on the health of at-risk people. The total hardness also did not have many fluctuations with a maximum value of 390 mg, which seems fairly favorable, since a concentration of 300 mg is optimal for this variable, and 600 mg is the maximum total hardness of drinking water. The interpolation maps of the groundwater quality index indicated that in the summer of 2014, most of the districts were considered to be in bad and medium conditions, but in the winter of the same year, the conditions changed to medium and relatively good. The water quality index for toxic pollutants in the mentioned seasons and years was in good and very good levels, indicating the groundwater was not polluted by the toxic variables used to determine the index. Conclusion: The reported data for physiochemical and microbial variables showed that the groundwater in the study area had not serious problems, and only the water turbidity exceeded the standard level. Using chlorine disinfection processes to eliminate coliform bacteria and treatments to reduce water turbidity seem to improve water quality. The calculated groundwater indices for the district water indicated that most of the ward, in terms of conventional pollutants, was in the bad-to-medium category in 2014, while in 2016, the quality category changed to medium to fairly good.
