Original Article
Alireza Amolikondori; Kambiz Abrari Vajari; Mohammad Feizian
Abstract
Introduction: Diverse gap sizes have formed in temperate Hyrcanian forests as a result of different silvicultural operations. Understanding the consequences of these practices on forest stand dynamics can help in deciding the choice of silvicultural methods. Therefore, the purpose of this study was to ...
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Introduction: Diverse gap sizes have formed in temperate Hyrcanian forests as a result of different silvicultural operations. Understanding the consequences of these practices on forest stand dynamics can help in deciding the choice of silvicultural methods. Therefore, the purpose of this study was to investigate the effect of canopy gaps on the carbon stock of beech trees and compare it with the adjacent stand and also the interaction between tree attributes and their carbon stock.Material and methods: The created gaps from single-tree cutting were classified in three classes of small, medium and large area with five replicates for each. Trees were also identified in the adjacent forest to each gap at a distance of 20 m from four directions of them. Tree height, DBH, surface area, volume, length, diameter of crown and carbon stock of trees were measured. One-way analysis of variance was used to compare the average carbon stock index of beech trees in canopy gaps and in different situations as well as for large diameter trees. Independent t-test was applied to compare the average carbon storage in the height classes of the trees and also between the adjacent forest stands with the canopy edges. Pearson correlation coefficient was used to determine the correlation between the index of carbon stock amount with some structural features of beech trees in the edge of the canopy gaps and the adjacent forest stand.Results and discussion: The findings revealed that the carbon stock of beech trees along the gaps' edges differed significantly (p≤0.05). No significant difference in carbon stock was observed for beech trees among different directions at the edge of the gaps (p≤0.05). There was no significant difference between the mean value carbon storage of trees at the edge of the gaps and the adjacent forest (p≤0.05). The highest mean of carbon was observed in the large-sized trees (3725.28 ± 584.49) at the large gaps. The results of correlation showed that with increasing DBH, height, length and diameter of the crown and the volume of the crown, the amount of carbon storage of trees increased at the edge of the gaps and also in the adjacent forest (p≤0.01). Conclusion: Findings indicate the effect of canopy gap area resulting from the implementation of single-tree selection method in beech forest. The correlation between the structural characteristics of beech trees such as DBH, height and crown area with carbon stock shows that when applying silvicultural methods (tending and logging) in Hyrcanian forests, structural characteristics Beech trees, especially the abundance of large-sized trees, should be considered with more carbon stocks in them.
Original Article
Zahra Jafari; Amir Salemi
Abstract
Introduction: Reaction of disinfection reagents, particularly chlorine, with natural organic material existing in raw water, results in production of a wide range of organic compounds, also known as disinfection byproducts. Despite their sever impacts on human health, only a tiny fraction of disinfection ...
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Introduction: Reaction of disinfection reagents, particularly chlorine, with natural organic material existing in raw water, results in production of a wide range of organic compounds, also known as disinfection byproducts. Despite their sever impacts on human health, only a tiny fraction of disinfection byproducts is regulated and controlled.
Material and methods: In the present work, a novel solid-phase microextraction Arrow coupled with GC-MS has been developed, optimized and implemented for determination of seven non regulated disinfection byproducts; trichloroacetonitrile, dichloroacetonitrile, 1,1-dichloro-2-propanone, chloropicrin, bromochloroacetonitrile, 1,1,1-trichloro-2- propanone and dibromoacetonitrile. A central composite design was used to optimize the extraction parameters.
Results and discussion: The method was sensitive enough to detect traces of the target compounds, with LOD values of 0.4-20 ng L-1. Also, quantitative analysis was possible over a wide linear range of about four orders of magnitude (50 to 100000 ng L-1 with R2 values of more than 0.997) with reasonable precision (RSD% values of less than 21.6% at 50 ng L-1. relative recoveries were between 60 and 95 %.
Conclusion: The optimized technique was also successfully implemented for determination of the target compounds in ten drinking water samples and as result, most of them were observed in various concentration levels.
Original Article
Amir Bahrami; Fatemeh Ahadi; Mehdi Bahrami; Fateme Aghamir
Abstract
Introduction: Today, treated wastewater is widely used on agricultural soils adjacent to urban areas of developing countries to meet water shortages. On the other hand, due to the pollution increase, the limited available resources are threatened. For the production of crops, unconventional water is ...
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Introduction: Today, treated wastewater is widely used on agricultural soils adjacent to urban areas of developing countries to meet water shortages. On the other hand, due to the pollution increase, the limited available resources are threatened. For the production of crops, unconventional water is used in many countries of the world if it has the necessary standard, and municipal wastewater treatment plants are a very reliable source due to their ability to deliver sustainable water in all seasons. In recent years, several studies have been conducted in the field of the effluent quality of municipal wastewater treatment plants and the possibility of using them in various applications, including agriculture, in different regions of Iran. Due to the water crisis that has arisen, especially in arid and semi-arid regions of the country, it is necessary to study and analyze the possibility of further use of this unconventional water resource. However, wastewater recycling can have various health and environmental effects.Material and methods: In this study, the effluent quality of the Shiraz municipal wastewater treatment plant was investigated using the daily data during 2018 and 2019 for use in various purposes such as irrigation of crops, irrigation of green spaces, drinking of livestock and poultry, fish farming, discharge into streams, artificial recharge of groundwater based on national and international standards. In this regard, at first, the values of various physical and chemical parameters such as acidity, electrical conductivity, total dissolved solids, total suspended solids, total volatile solids, total solids, chemical oxygen demand, biochemical oxygen demand, turbidity, dissolved oxygen, detergents, phosphate, total phosphorus, nitrate, nitrite, ammonia, Kjeldahl total nitrogen, free chlorine, and fat-oil-grease were determined in raw and treated wastewater. Then, while comparing the values of these parameters with the standard of the Environmental Protection Organization of Iran, the removal efficiencies of these parameters were calculated and finally, the quality of the effluent was investigated for use in various sectors.Results and discussion: The results showed that the removal efficiency of BOD5, COD, TSS, NH3, detergents, and fat-oil-grease in this treatment plant is 85, 85, 67, 64, 94, and 68.5%, respectively. The quality of the effluent is only suitable for agricultural purposes based on the standard of the Environmental Organization of Iran, and according to other standards, it is not capable of such use. This effluent can be used to irrigate ornamental fruit trees, fodder crops, plenteous trees and green spaces side of the roads outside the city, field crops, industrial crops, and forestry, as well as drinking livestock and poultry. However, there are limitations for urban green space irrigation, fish farming, discharge to surface waters (such as Maharloo lake in the vicinity of the wastewater plant), and groundwater recharge, although some of these limitations can be improved by upgrading the function of the treatment plant. By irrigating unfruitful plants and forest parks around Shiraz and even part of urban green space, the pressure on water resources can be reduced to a great extent. On the other hand, the continuation of irrigation with this effluent, which contains organic and nutritious substances in a large proportion, has caused an increase in soil nitrate, and it will be possible to leach and transfer it to surface and underground water sources.Conclusion: The amount of quality parameters of the treatment plant effluent is within the standard of Iranian Environmental Protection and can be used as a sustainable water source in areas that are not directly related to humans. In using this sustainable water source for permitted uses, all health issues for the workers of each sector must be observed, and the effluent must be continuously disinfected.
Original Article
Masoumeh Sharifi; Bagher Nezami Balouchi; Javad Ramezani; Behzad Rayegani; Ali Jahani
Abstract
Introduction: The brown bear (Ursus arctos) is the largest carnivore which has a wide range of distribution but like other large carnivores, there are low frequency in the country. Habitats of this species in the country, especially at the local level are very fragmented. Therefore, investigation and ...
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Introduction: The brown bear (Ursus arctos) is the largest carnivore which has a wide range of distribution but like other large carnivores, there are low frequency in the country. Habitats of this species in the country, especially at the local level are very fragmented. Therefore, investigation and recognition of the potentially suitable habitat regions are of great importance in the conservation of this species. Also, identifying the factors affecting the selection of habitat plays an important role in describing species behavior and allows to compare different habitats in terms of their quality and to use it in the effective management. Evaluating the response of models and impacts of the biogeoclimatic factors, on habitat suitability, are the other goals of this study.Material and methods: This study was performed in the northwestern part of Iran in the Arasbaran ecoregion, which is known as the Caucasian geographical climate. The Caucasus ecoregion part of Iran has two separate plant communities, Hyrcanian and Arasbarani. The definite presence points of this species were identified by conducting field visits and collecting confirmed observations and reports of game wardens and experts and 64 points were employed in modeling after validating the obtained points and applying the buffer. Six modeling techniques were used in the BIOMOD package of software to create an efficient species distribution model and identify potentially suitable regions. Finally, the habitat suitability map was acquired from the resulting outputs using the combined Ensemble method.Results and discussion: The results from the models’ outputs and overlapping the map of the protected areas indicated that more than two-thirds of these areas are suitable for the brown bears. based on results, the variables of slop percentage and vegetation index involve the largest share in determining habitat desirability, so moderate slop and higher vegetation density will lead to more suitability for the species. In determining the desirability of the habitat of the brown bear, the variable of distance from rivers has less effect, and distance from the village did not play an important role. The flatness of areas, as it increase human access, reduced the level of security and thus reduced the suitability of the habitat of this species. There is more probability of the presence of species in the slope range of 10 to 40% and the suitability of habitat was raised in the moderate slope and increased the vegetation density. Regions with moderate rainfall and higher altitudes also play an important role in attracting bears and increasing habitat suitability. On the other hand, rising temperature, congested roads, and increasingly concentrated human activities reduce habitat desirability with an almost steep trend. 67% of the identified suitable and preferred habitats of the species have been located within the four protected areas category and 33% of them are outside of these areas, which is an acceptable level for conservation. Although a wide range of the protected areas in the study area is suitable for the species, the density of the brown bears in this part of the country is much lower than in the north and west of the country. This is maybe due to the high number of human casualties and damages in these areas and that most areas are not broad and wide enough to cover the entire home range of this species in the northwest. The most common reason for habitat fragmentation is the local road network, dispersion of rural areas and dispersed villages, and scattered individual livestock farming.Conclusion: One of the most significant conservation strategies for the large carnivorous species, such as the brown bear, with high mobility behavior, low population density, high conflict, and extensive conservation requirements is connectivity between the species habitats by defining new protected areas according to the suitable habitats maps. Also, the most important actions to reduce conflict and retaliatory measures are organizing the scattered livestock farming, implementing the educational programs, and more importantly, compensating the damages caused by bears to rural communities.
Original Article
Elham Pourmaafi Esfahani; Ali Almodaresi; Mohammad Mousaei Sanjerehei; Hamed Hghparast
Abstract
Introduction: Today, dust phenomena are among the most important environmental hazards and pose a serious threat to human health and the environment. Dust in barley as one of the pollutants has various adverse effects and negative consequences, among which can be reduced growth and yield of agricultural ...
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Introduction: Today, dust phenomena are among the most important environmental hazards and pose a serious threat to human health and the environment. Dust in barley as one of the pollutants has various adverse effects and negative consequences, among which can be reduced growth and yield of agricultural products, intensification of damage caused by pests and plant diseases, increased road accidents due to reduced visibility, The cancellation of flights and the resulting financial losses, increased treatment costs, closure of industrial units, pollution of water resources, increased erosion of buildings, decreased efficiency of solar photovoltaic systems due to turbidity.Objective: Therefore, due to the importance of dust and in order to predict how dust is spread, the artificial neural network model was used. This model can be useful and cost-effective information for future implementation of air pollution control strategies and cost reduction.Material and methods: To model the dust distribution using artificial neural network model, statistics and meteorological information of Kashan synoptic station, which were recorded daily by the Environment Department in 1996, were used. The proposed neural network model has four input layers that include humidity, temperature, wind speed, wind direction and an output layer, the daily concentration of suspended particles is 2.5 micrometers per cubic meter. The model training process was performed using multilayer perceptron neural network and post-diffusion rule and using sigmoid membership function in Matleb software environment. In the neural network model, the number of neurons in the hidden layer and the appropriate number of rounds or IPAC to achieve the best neural network structure, with the least error for each model, were determined using trial and error. The number of neurons and apex for the model in 2017 is 15 and 37,000, respectively.Results and discussion: The correlation coefficient of the model for predicting PM2.5 concentration is equal to 0.80 which is obtained by comparing real data with simulated data. The validation results of the model with real data are close to 80%, so the neural network model can be used to predict PM2.5 concentration. According to the average regression diagram, the predicted values obtained from the model are closer to the diagonal axis and have no dispersion. Also, based on the results of the step-by-step regression method, it was determined that among the four variables used for relative humidity modeling, it has the most impact and importance in dust emission modeling.Conclusion: According to the accuracy and the results, this method can be used to predict the air pollution of Kashan caused by suspended particles. Due to the high capability of the perceptron neural network in predicting the concentration and distribution of dust, the application of this model can be a suitable and fast solution for predicting the amount and spread of dust.
Original Article
Saleh Mahmoudi; Asghar Abdoli
Abstract
Introduction: Finding habitat requirements for fish in fluvial water ecosystems is a key factor in conservation and decision making for their management, which unfortunately does not have enough scientific information in this field. The purpose of this study is to identify the optimal range of habitat ...
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Introduction: Finding habitat requirements for fish in fluvial water ecosystems is a key factor in conservation and decision making for their management, which unfortunately does not have enough scientific information in this field. The purpose of this study is to identify the optimal range of habitat variables for Alburnus atropatenae in the Jajroud protected river and compare different composite approaches in the modeling of this species.Material and methods: In this study, the habitat of A. atropatenae sampled in the form of 71 points in the Jajroud river. Physical variables of habitat measured including depth, water velocity and substrate type. After sampling the fish by electrofishing, the total length of the fish measured. Habitat suitability curves developed by univariate method then combined habitat suitability calculated by multiplication, minimum, arithmetic mean and geometric mean methods. To validate the results, two statistical metrics of mean absolute error (MAE) and root mean square error (RMSE) used.Results and discussion: Overall, 235 individual of A. atropatenae caught including 221 adults and 14 juveniles whose total body length varied from 23 mm to 148 mm. Physical habitat variables included a depth of 6-56 cm, a flow velocity of 4-29 cm / s, and a riverbed with a particle size of "very fine gravel" to "small cobble". The preferred and optimal range habitat for this species included a depth of 16-25 cm, a flow velocity of 5-10 cm / s and a bed with small cobble structure. Among univariate models, the riverbed-based model had the lowest error. Among the models of combined habitat suitability, multiplication method had the lowest values of MAE and RMSE measures, and was low-error model. The arithmetic mean method had the highest values of these measures and had detected as the high-error model.Conclusion: This is the first study related to the ecology of A. atropatenae in Iran, which has identified the optimal habitat of this species. The variable of bed structure is determinative more than two variables of depth and flow velocity in habitat selection by this species. Also in combined habitat suitability modeling, the multiplication method has priority and importance.
Original Article
Ramin Alivand; Omid Noori; Hadi Veisi; Reza Deihimfard
Abstract
Introduction: Beginning and developing community gardens in city by creating a healthy and intimate atmosphere, it has made people feel refreshed and by increasing social, cultural and political participation It can be helpful in solving people's problems in the region, city and even the country. By ...
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Introduction: Beginning and developing community gardens in city by creating a healthy and intimate atmosphere, it has made people feel refreshed and by increasing social, cultural and political participation It can be helpful in solving people's problems in the region, city and even the country. By creating a community garden, in addition to continuing to maintain the gardens, can also benefit from the services and functions of these gardens. In this research using Network analysis and ranking of indicators and their relationships in the decision-making process.Material and methods: This research was conducted in Karaj city, based on different criteria and according to the opinion of framework experts to develop Community gardens Provide multi-function and multi-service. to reach this goal, used from the model provided for the services and functions of the community garden which has eight economic, political, social, cultural, ecological, environmental, educational and health dimensions, And with 125 components. In this research, data collection Using a questionnaire Based on ANP decision technique and pairwise comparisons by professionals with at least 15 years of experience which were selected by the snowball method. After calculating the geometric mean of the judgments made the information entered the software. The processing and analysis of the results of this research was done using Excel and Super decision software.Results and discussion: After measurement the weight of the used indicators, the final prioritization for the proposed functions and services was done by the super decisions software. Among the investigated indicators Stability index (2C) with a weight of 0.389 The most important indicator of choosing the services and functions of the community garden and after this index, Acceptability index (3C) with a weight of 0.228 and effectiveness index (1C) with a weight of 0.205 They were ranked next. Based on the calculation with weighted indicators, Among the functions of community garden dimensions The economic dimension of "Using Abandoned Lands", social dimension of "entertainment space", political dimension of "tourism", cultural dimension of "developing garden endowment culture", environmental dimension of "pollution reduction", ecological dimension of "biodiversity", health dimension "healthy body weight", educational dimension of "Environment for promoting agriculture" They got the highest priority.Conclusion: The results of this research can in showing the position of the community garden very useful by people and officials and to justify investment in order to benefit from the services and functions of the community garden. Due to the importance of the community garden, when designing the city, there should be a plan to provide urban green infrastructure. Based on the knowledge of services and functions of these gardens to be considered necessary in accordance with social preferences.
Original Article
Adel Khazaei; Majid Abbaspour; Sasan Babaei Kafaky; Lobat Taghavi; Yousef Rashidi
Abstract
Introduction: The metropolis of Tehran as the largest capital of the Middle East is faced with phenomena such as environmental degradation, land use change and high concentration of agricultural and industrial disasters. Knowing the changes of land use in the past and predicting its future status is ...
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Introduction: The metropolis of Tehran as the largest capital of the Middle East is faced with phenomena such as environmental degradation, land use change and high concentration of agricultural and industrial disasters. Knowing the changes of land use in the past and predicting its future status is necessary in order to carry out a principled, dynamic planning. In this study, the spatio-temporal dynamics of land use changes in the Tehran in a 20-year period and the prediction of future changes in these land uses in the next 40-year were selected as the general objectives of this study.Material and methods: After forming a database of Landsat 5 and 8 satellite images for three times of 2001, 2011 and 2021, the land use map of this times were prepared. For the validation of the maps Google Earth images, ground points and accuracy and Kappa coefficients were used. The time period from 2021 to 2061 was considered to predict future changes. In order to zoning and predict the future of land use changes, 6 land use change transfer sub-models with artificial neural network, Markov chain, and LCM model were used. Evaluation of the accuracy of the model was obtained from the comparison of the ground map of 2021, the future map of 2061, and the values of Null success, success, Miss and False Alarm were obtained.Results and discussion: The results showed that the period from 2001 to 2021 was associated with the expansion of residential areas, the growth of urban areas and the reduction of green spaces including gardens and parks. The expansion of residential areas has been primarily in poor and barren soils and then in gardens and green spaces. This urban growth was clearly in region 5, 21, 22 and its physical development process was linear. The decrease in the level of gardens and green space is very catastrophic and this decrease is especially evident in the central areas of the city due to the high density of buildings. Urban parks are clearly in a complicated condition in the eastern areas of Tehran. The area of rain fed agriculture has increased and the area of barren soils and poor lands has decreased. Most of the changes in land use related to low capacity lands and agricultural lands have occurred. Studying the maps of the future of land cover showed the continuation of the same trend of the past 20 years. Although the growth of residential areas will be slower than the previous period, but the capacity and dimensions of the city will continue to increase, especially in the western, southern and southwestern regions. The decreasing trend of gardens, parks and urban green space is still observed. This process is more intense in the case of parks and they will be destroyed more quickly. The reason for this is besides drought and withering of trees due to climate change, pollution, and conversion of these green land uses to rain fed agriculture, parks, poor rangelands and urban areas. As for the urban green spaces, the 16 and 4 regions have the worst positions, and the 17, 19. 2, 5 and 22 regions will not be safe from this damage either. The decrease in the area of rangelands and cities moved to new areas will increase; the cycle of destruction of vegetation will increase from the outskirts of Tehran.Conclusion: Construction was more in the south of Tehran and the decreasing trend of urban green space will continue to be observed. The central areas of Tehran will be completely devoid of trees due to the predominance of the urban areas, and the point to consider is the destruction of the green belt in the north of Tehran in the future.
Original Article
Maryam Shariatzadeh; Masoud Bijani; Saeid Morid
Abstract
Introduction: Any long-term changes on the weather conditions are called climate change. The most critical environmental threat against the earth planet is the climate changes on these days. In other hand, the climate changes which has increased so fast in these decade has caused the water managers, ...
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Introduction: Any long-term changes on the weather conditions are called climate change. The most critical environmental threat against the earth planet is the climate changes on these days. In other hand, the climate changes which has increased so fast in these decade has caused the water managers, the water consumers and the all authorities and planners face with serious challenges and there is no clue. It does not seem there is logical way to assume that the climate changes and hydrological conditions are going to remain in the same structure as they have been before. Therefore, the important issue is making a useful plan to avoid and control effects of climate changes while we are facing serious challenges by the impacts of climate. The climate changes has made a bad impact on the agricultural part in the different regions of world, so farmers need to be adapted more with these changes to save their livelihood. This research is done based on understanding how the farmers are adapting with the climate changes by using of the behavioral model in Khoy Township.Material and methods: The present quantitative research as an applied inquiry which has been done in the descriptive-correlational method in Khoy Township. The statistical population was 25811 households which 380 of them was selected based on Krejcie and Morgan sample size table and stratified random sampling method. The research instrument was a questionnaire which its face and content validity was confirmed by a panel of expert in the field of agricultural extension and education and its reliability was confirmed with Cronbach's alpha (0.72 ≤α ≤0.90) in order. The descriptive and inferential statistics is used for data analyzing.Results and discussion: The results showed that the level of adapting for the all farmer households is not equal. At the end we will provide the model of the farmer household adapting to the climate change and also useful and effective methods to reduce of the negative effects of climate changes on rural households. Based on the findings the most important effective factors on adapting are keeping the agriculture structure, living standards, social solidarity, using of various strategies for adapting, learning new ways to fight with crisis and keeping the power of decision that have most relation with adapting. On the other, maintaining the mood has less relation with the dependent variable. The independent variables anticipate 87% of the dependent variable's changes.Conclusion: The results show that households increase their ability to adapt to climate change economically by using different strategies and new crisis response strategies. Evaluating farmers' actions on climate change also shows that most farmers are aware of the effects of the climate change and are able to maintain and improve their livelihood. So we can create a sustainable situation for adaptation to climate change by presenting new techniques to local farmers and updating climate information.
Original Article
Somayeh Moharami; Mahdi Sadeghi Pour Marvi; Rahman Sharifi
Abstract
Introduction: During the past two decades, computer aid models for simulation of heavy metals have been remarkably developed. Prediction of soil pollution plays an important role in pollution control and land management. But in large areas, collecting data in a direct way is challenging in terms of cost ...
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Introduction: During the past two decades, computer aid models for simulation of heavy metals have been remarkably developed. Prediction of soil pollution plays an important role in pollution control and land management. But in large areas, collecting data in a direct way is challenging in terms of cost and time. In recent years, the use of indirect methods such as artificial neural network (ANN) and other similar models to estimate heavy metals has been considered. There are 27 salt mines in Garmsar city. Of these, 16 mines are active. Salt extracted from these mines are used as one of the food spices. On the other hand, due to mining activities, the soils of this region may be contaminated with heavy metals. Therefore,in this study, the effectiveness of terrain and spectral indices for predicting total soil Cadmium (Cd) around the soils of Garmsar salt mines was evaluated by ANN – multilayer perceptron (MLP) model.Material and methods: For this research, 49 soil samples were collected from the 0-20 cm Physicochemical properties of soil samples such as percentage of clay, sand, silt, soil acidity (pH), electrical conductivity (EC) and lime percentage were determined. Total Cd concentration was measured by atomic absorption spectroscopy (AAS) (Varian, Spectra 220). All terrain attributes used in this study were derived from a digital elevation map (DEM) and to calculate the spectral indices, Landsat-8 OLI/TIRS bands image with a resolution of 30 meters were used. Twenty-five auxiliary data variables derived from a DEM and Landsat-8 were used to predict total soil Cd in the study area. Based on the auxiliary data obtained and the correlation coefficients between these data and the predicted total Cd value, 2 models were evaluated. The collected data were randomly divided into categories training and validation and were used to evaluate the MLP model.Results and discussion: The results of this study show that the auxiliary data extracted from landsat-8 bands (with the highest accuracy and lowest error rate) were the effective parameters in predicting soil contamination with Cd. Based on the results obtained from the evaluation of ANN performance in estimating total Cd, the value of root mean square error (RMSE) and coefficient of explanation (R2) were 0.05 and 0.95 for the first model and 0.10 and 0.80 for the second model. In model 1, saturation index (Sat I), grain size index (GSI), carbonate index (CrI), soil color index (color I) and gypsum index (GI) were important and main parameters in total Cd modeling. The results of the present study showed the high efficiency of the ANN model in predicting total soil Cd.Conclusion: Due to the development of machine learning models in the field of environmental engineering especially in simulation of heavy metals, having a turning point for their advancement is very important. The results of this research show that the MLP model is suitable for total soil Cd prediction and this method can save the cost of soil sampling and analysis. Therefore, it is recommended to validate the method applied in this study to prepare total soil Cd map in similar areas.
Original Article
Toktam Shahriari; Abdolreza Karbassi; Maryam Shirazinejad
Abstract
Introduction: Industrial plating wastewater contains various types of detrimental heavy metals in high concentrations. One of this toxic metal is Nickel that its discharge into the surface waters and soil is considered as an environmental problem. Hence removing of this metal from wastewaters is crucial ...
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Introduction: Industrial plating wastewater contains various types of detrimental heavy metals in high concentrations. One of this toxic metal is Nickel that its discharge into the surface waters and soil is considered as an environmental problem. Hence removing of this metal from wastewaters is crucial and vital for protecting the environment and human health. Applying of nanotechnology in elimination of environmental contaminants is one of the methods which attracted a great deal of attention in recent years. In present research, nanographite was utilized as efficient adsorbent in order to remove Ni ions.Material and methods: In order to investigate the adsorption process, nanographite with a purity of 99.9% and a specific surface area of 18-24 m2/g and a plate morphology was prepared from Pishgaman Iranian Nanomaterials Company and used as an adsorbent. Also, the wastewater used in the experiments was prepared from one of the plating workshops in Tehran, which contained 765 mg/L of nickel and a pH of about 1. The parameters of pH, time and amount of adsorbent were evaluated. In each experiment, one of the parameters was considered variable and the other two parameters were considered constant. The amount of nickel was determined before and after each test.Results and discussion: In this study, the parameters including pH, adsorption time and adsorbent dosage were investigated as effective factors on Ni adsorption process. In order to analyze the adsorption mechanism, the obtained results were examined by the Langmuir and Fruendlich isotherm models. In addition, pseudo-first-order and pseudo-second-order models were studied to investigate adsorption kinetics. According to the results, the Ni uptake by nanographite was enhanced significantly with increasing of the pH value from 5 to 7. Thus the pH of 7 was determined as optimum pH for Ni removal. Investigations also showed that increasing the time up to the first 80 minutes had a relatively good effect on nickel adsorption by the nanoparticle, and after that the adsorption almost reached equilibrium. Finally, it was observed that in a constant time, increasing the amount of adsorbent led to an increase in adsorption, and to achieve the maximum adsorption of nickel, the amount of 2g was chosen for the adsorbent. Based on the obtained results, 97.52% primary nickel was adsorbed by nanographite. Results also revealed that the data were best fitted to the Fruendlich models. After determining the amount of nickel adsorption at different times, the resulting data were analyzed by the kinetic model.Kinetic studies also indicated that the adsorption data were described well by pseudo-second-order model. Conclusion: Examining the results showed that pH plays an important role in the adsorption process and the adsorption rate increases with increasing time until the equilibrium time is reached. One of the effective factors is the amount of adsorbent, which has a direct effect on adsorption. Following the Freundlich isotherm in this research indicates that the adsorption sites in the adsorbent have different energies. Also, the pseudo-second-order model in adsorption kinetics refers to the process of chemical adsorption in addition to physical adsorption.
Original Article
Ali Khodaie; Rahman Zandi
Abstract
Introduction: The lack of proper management and the lack of choosing the right place for disposal and burial of waste creates problems for the human and animal environment. Khoda Afarin city has a population of about 34977 people and Kalibar city has a population of about 48837 people. In the last few ...
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Introduction: The lack of proper management and the lack of choosing the right place for disposal and burial of waste creates problems for the human and animal environment. Khoda Afarin city has a population of about 34977 people and Kalibar city has a population of about 48837 people. In the last few decades in these cities, with the increase in population, consumerism, and the change in people's eating habits, the increase in the consumption of packaged materials along with the imitation of people's consumption pattern has caused an increase in the production of a large amount of waste. Despite this problem, there is still no proper way to dispose of waste in these cities. The purpose of this research was to locate landfill centers based on ANP network analysis process model and Boolean logic in GIS environment by using the opinions of expert experts in the form of pairwise comparison questionnaires and descriptive-analytical method.Material and methods: In this research, in order to select landfill centers due to the complexity of the influencing factors, the necessity of using geographic information technologies (GIS) and its integration with other management and planning matters has been proposed; Therefore, in this research, ARC GIS software has been used to create databases, spatial analysis and superimposition of information layers, as well as ANP model and Super Decision software to calculate criteria weight and Boolean logic model.Results and discussion: In this research, 17 layers of information include; Surface water resources, slope, city and village areas, protected areas, fault, soil, road network, litology, land use, erosion, NDVI, dem, climate, land side, dam, aspect Then, in the network analysis process model, Super Decision software was used to apply weights for each of the criteria, and in the ArcGIS environment, the information layers were combined with the final weight, and the value of each cell was determined in the final map. The area of 369221 hectares was divided into four categories: unsuitable 174720 hectares, relatively unsuitable 146677 hectares, suitable 42670 hectares and completely suitable 5154 hectares in terms of landfill location, and in Bolin logic, the estimated area of unsuitable 365457 hectares and suitable 3938 hectares for landfill location Garbage detected. Finally, due to the closeness of the areas to each other, the final maps of both models were overlapped, and after merging the locations of 2679 hectares, a suitable location was determined, which covers 73 percent of the suitable areas of the Boleyn model.Conclusion: The comparative analysis of the results shows that finally, in the ANP model, only 1.4 percent of the area of the area is completely suitable, and in the Boleyn model, 1.2 percent of the area of the area has optimal conditions for the landfill. One of the most important achievements from the results of this research is the use of a completely suitable place and the final result of the map from this research.
Original Article
Farhad Hosseini Tayefeh; Saber Ghasemi; Mona Izadian; Seyyed Ghasem Ghorbanzadeh
Abstract
Introduction: Anatidae family is considered as a biological indicator of wetlands due to their migratory behavior, wide distribution and high population density. Three wetlands of the Bakhtegan basin, namely Bakhtegan, Tashk and Kamjan in Fars province, are important habitats for Anatidae in the central ...
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Introduction: Anatidae family is considered as a biological indicator of wetlands due to their migratory behavior, wide distribution and high population density. Three wetlands of the Bakhtegan basin, namely Bakhtegan, Tashk and Kamjan in Fars province, are important habitats for Anatidae in the central plateau of Iran. The purpose of this research was to evaluate fluctuations in the wintering population of the Anatidae family in wetlands of the Bakhtegan basin in a long-term period of 52 years from 1967 to 2018.Material and methods: Data on the population and diversity of waterbirds were obtained from a 52-year census data of the Department of the Environmental of Iran. Results of field studies in 2019 were also used to investigate their current habitat condition, data validation and monitoring of Anatidae populations. Of 21 Anatidae species recorded in Iran, nine species with a population of more than 50 individuals per year and observed at least 20 years, were investigated along with the Vulnerable species (VU) of Common Pochard Aythya ferina. Annual changes in the total population of waterbirds, the number of species in each year, the proportion of Anatidae in the population and the diversity of waterbirds in Bakhtegan wetlands and the statistical trend of population changes of species were analyzed. Trend of long-term changes in the population of Anatidae species were calculated using the RTRIM statistical package and Multi-species Indicators (MSI).Results and discussion: A total of 21 of Anatidae species, including Endangered species (EN) of White-headed Duck Oxyura leucocephala, Marbled Duck Marmaronetta angustirostris (VU) and Common Pochard (VU) and Near Threatened species (NT) of Ferruginous Duck Aythya nyroca were identified in the wetlands of Bakhtegan basin. The average population of Anatidae in a 31-year period (1988–2008) was more than 169,000 individuals, but in the last ten years (2009–2018), it decreased to 6,623 individuals. The highest number of total population was in 1995 with 632,510 individuals and the lowest with 1,135 individuals in 2016. The highest and lowest number of species were in 2000 and 2010 with 13 and 3 species, respectively. The statistical trend of the population changes showed that the Greylag Goose Anser anser faced a steep decline in the long-term with a slope of -21%, the Shelduck Tadorna tadorna with a steep decline (-8.4%), the Ruddy Shelduck Tadorna ferruginea with a stable population and zero percent, the Mallard Anas platyrhynchos and the Eurasian Teal Anas crecca with a steep decline and slope of -12.1% and -6.5%, respectively. Trend of changes in the last ten years for the Greylag Goose was stable (0.1%), Shelduck with an uncertain state (4.8%), Ruddy Shelduck and Mallard with a decrease and a slop of -3.8% and -9.4%, respectively, and Eurasian Teal with a strong increase (48.9%). The results indicate that Bakhtegan wetlands had a high proportion of waterbirds during the 1990s to the early 2000s, but it has lost its position in the last 15 years. Bakhtegan wetlands used to be the breeding habitat for Marbled Ducks, but there have been no reports of its breeding in recent years.The reduction of water level, drying wet areas and changes in habitat variables have been the most important factors in reduction of the population and diversity of Anatide species.Conclusion: The Anatidae family has more than 30% of species diversity and more than 53% of the total population of waterbirds in Bakhtegan wetlands. Currently, it is possible for birds to spend the winter in only a small part of Tashk wetland in the area of Gamban spring. Reconstruction, restoration and making continuous and effective protection of the wetland chain of Bakhtegan Basin requires allocating the required water from diverse water sources for its biological sustainability. In the case of increasing the level and depth of these water areas, the possibility of increasing the population and diversity of diving ducks and Mergus species is expected. Due to the importance of the participation of stakeholders in the protection and restoration of wetlands, it is necessary to take action regarding the allocation of biological water rights and participatory protection of wetlands according to the social, economic, cultural and political conditions.
Original Article
Fatemeh Zolfaghariyan; Alireza Koocheki
Abstract
Introduction: Today, environment is globally facing extensive challenges including climate change and global warming, soil erosion, reduced biodiversity and hence lack of resilience and ecological balances. This has been caused by improper use of environmental resources in the context of economic growth ...
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Introduction: Today, environment is globally facing extensive challenges including climate change and global warming, soil erosion, reduced biodiversity and hence lack of resilience and ecological balances. This has been caused by improper use of environmental resources in the context of economic growth and development based on imbalanced population growth, world market inequities and world economic patterns and also unfair distribution of wealth in the in the most part of the world particularly in the third world countries. In this respect two views, one based on western vision of development and other on the Marxist attitude have been evolved which brought up arguments and conflicts in political societies and developed conflict analysis and interpretations, related to the causes of the present environmental degradation and problems. In the late 1960s, which was a turning point, in attrition towards the global environment, these paradigms were also developed and resolutions based on the attention economic, social and political aspects were evolved. In that period different disciplines associated with ecological principles such as political ecology, political economy and environmental economy were structured and philosophical approaches on the interactive impact of human with environment was also introduced. On this respect with expansion of challenges related to the present world environment, analysis based on the political ecology and approaches for solving problems are needed. The purpose of this article is to analyze the global environmental challenges from the point of view of political ecology and present the existing views from the political and social dimensions in this field.Material and methods: The nature of this type of studies are mainly based on the literature and documents available and also consultation with the experts. There for in this study this approach was employed and available integrated method was also taken into account. On the other hands since the study of political ecology is rather new availability of the appropriate documents and other related literature was a challenge.Results and discussion: Now political views on the detrimental effects of human on the environment based on the ecological principles was the reason for development of political ecology. Basically, ecological science is a political one which is sometimes also called subversive science (Sears, 1964). In the early 1970s political analysts were tired of the interpretation of environmental problems, which were political but population inappropriate technology and weak management were accused for this, therefor in this respect political ecology was developed (Blaikie and Brookfield, 2015). With no doubt integration of natural and social sciences broadens our understanding of the need for sustainable development, but unfortunately the political side is normally ignored and practically ecology is depoliticized. Although sustainable development is a tight segment of the process of interrelationship between human and the environment, most scientific sources lacks political elements. Political ecology emphasizes on the political elements and emphasizes on the political actors, conditions and consequences, interplay of diverse social and political forces and their interrelationship with the environmental changes as the same role as ecological science plays in the interpretation of the relationship between the living organisms and their ecosystems.Conclusions: for growth and development no matter what the views and ideological paradigms are, whether as a capitalism economy or Marxist prospective, today global environment is endangered with serious challenges. For facing these problems, a worldwide unity in policy and decision making is required whereby a so called "think globally act locally" principle could be achieved. On the other hand, approaches proposed should be holistic based on the ecological thoughts in the frame of the main components of society, economy and the environment.
