Original Article
somaye arazi; mohammadhosein irannezhadparizi; Ahad sotoudeh; bahman kiani
Abstract
Background: Landscape of an area consists of uniform parts of that land that have components of patchs, passages and bed of land landscape. Since the density and distribution of vegetation in the landscape of the land of the passage of time is affected by many variables and changes. Variety and uniformity ...
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Background: Landscape of an area consists of uniform parts of that land that have components of patchs, passages and bed of land landscape. Since the density and distribution of vegetation in the landscape of the land of the passage of time is affected by many variables and changes. Variety and uniformity of plants studies the effectiveness of the indicators of richness, diversity and uniformity of vegetation from the structure of the landscape.Materials and Methods: In this study, two variables of size and shape of patchs on the structure of the Adoroshk watershed were selected because these two variables are known as important components in the planning of areas for conservation purposes. For this purpose, first the identification and preparation of the map of the structure of the land address of Adoroshk was performed and then the desired map in Arc GIS 10.3 software with suitable image format and ready to enter FRAGSTATS 4.2 software and then two variables of ratio of environment to area and size The patchs in the structure of Adoroshk land were calculated. Data obtained from identification and counting of vegetation in the area, which were the result of linear transect and plot method, were also entered in SPSS software environment and through Shannon-Wiener, Simpson, Hill, Brillouin and MacArthur Plant diversity was measured using the Margalf, Mann-Henick index of plant richness in each spot of the habitat. The Pilo, Alatalo and Hip indices were also used to measure species uniformity. The correlation between the variables was determined from Pearson correlation.Results and Discussion: In this study, 60 plant species were identified and counted in 338 plots and the findings of this study indicate a significant relationship between the two physical variables of size and shape of habitat spots and richness. The diversity and uniformity of rangeland plant species in the Adoroshk watershed.Conclusion: The priority of paying attention to circular patchs that have a minimum ratio of environment to area in the design and management of Adoroshk watershed was proven during the planning and protection of vegetation.
Original Article
Jalalaldin Shahbaz; Zaniar Fatehi; Kamran Chapi
Abstract
Introduction: Global warming is the most important challenge facing man in the 21st century. Warmer weather will increase evapotranspiration, which will exacerbate droughts. One of the main causes of global warming is man himself. Humans have accelerated the Earth's climate change by producing large ...
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Introduction: Global warming is the most important challenge facing man in the 21st century. Warmer weather will increase evapotranspiration, which will exacerbate droughts. One of the main causes of global warming is man himself. Humans have accelerated the Earth's climate change by producing large amounts of greenhouse gases. For this reason, information about changes in the earth's temperature in the next decades has always been considered. The results of the researchers show that climate change has obvious and significant effects on temperature and rainfall in different parts of Iran in the next decades. By predicting and estimating the extent of these effects, climate change impacts can be mitigated with adequate preparedness, low cost, and greater speed.Material and methods: In this study, the effect of climate change on the mean maximum and minimum annual and seasonal temperatures in Arak under the emission scenarios of RCP2.6, RCP4.5, RCP8.5 for the 2040s was investigated. To use the output of General Circulation Models at regional and local scales is that they are using downscaling models, are downscaled. In this study, Statistical Downscaling Model (SDSM) to downscale output of General Circulation Models CanESM2 were used. This model had an acceptable ability to simulate the average maximum and minimum seasonal and annual temperatures in the study area. Results and discussion: According to the obtained results, the mean maximum temperature in winter and spring will decrease under all three scenarios RCP2.6, RCP4.5, RCP8.5, which can indicate that the daily temperature will be cooler in these seasons. However, the mean maximum temperature will increase in summer and autumn, which may indicate that the daily temperature will be warmer in these seasons. The mean minimum temperature in winter and spring under all three scenarios RCP2.6, RCP4.5, RCP8.5 will decrease and increase in summer seasons. These results show that in the 2040s, the city of Arak has colder night temperatures in winter and spring and warmer temperatures in summer and spring. Due to the fact that warmer weather increases the demand for water and electricity, and because Arak is an industrial city with a dry climate, it can face serious challenges of water and electricity shortage in the future.Conclusion: According to the results obtained in this study, in the 2040s, Arak will have colder winters and springs, and warmer summers and autumns. The highest effect of climate change on the temperature of Arak is related to the average minimum temperature in autumn, which under the scenarios of RCP2.6, RCP4.5, RCP8.5, the average minimum temperature in autumn increased by 206.88, 196.37 and 192.27 percent, respectively. The mean annual maximum and minimum temperature under all three scenarios will increase in the 2040s. The highest increase in the mean annual maximum and minimum temperature is related to RCP8.5 and RCP2.6 scenarios, respectively, which they are equal to 4.14 and 4.38.
Original Article
Asghar Abdoli; Fahimeh Rashidabadi
Abstract
Quantitative assessment of fish abundance is the basis of scientific research and management of their population. Demographic studies of stream-dwelling salmonids have shown that variation in their abundance s on a spatio-temporal scale is common, and brown trout populations are no exception. Understanding ...
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Quantitative assessment of fish abundance is the basis of scientific research and management of their population. Demographic studies of stream-dwelling salmonids have shown that variation in their abundance s on a spatio-temporal scale is common, and brown trout populations are no exception. Understanding this variation is crucial for several reasons, including designing and interpreting environmental impact assessment studies and monitoring fishery management strategies. The present study aimed to estimate the spatial and temporal variations in the density of brown trout in some of the Lar National Park streams and investigate the relationship between the density of fish in these streams and the density of benthic invertebrates as their primary food sources. In general, the purpose of this study was to assess the status of trout for conservation planning and better management of its populations in the future against human impacts and climate change. Since the Lar National Park streams are small, fish densities were calculated using the Le Cren depletion method to achieve reliable population estimates. After two removal steps, the total number of fish caught was standardized and expressed as density per 100 m2 of the river channel. To investigate the temporal changes of fish abundance, the study results in 2009 were qualitatively compared with the results of another study in 2017.According to the 2009 results, the highest brown trout density was recorded in the Delichay (44 per 100 m2), Lar (43.2 per 100 m2), and Siah Palas sites (33.4 per 100 m2), respectively, and the lowest density were recorded in the Lar (Kharsang, 10.5 per 100 m2) and Lar (Sorkhak, 11.5 per 100 m2). In 2017, the highest density of trout was documented to Siah Palas (175 per 100 m2), Delichay (Vararo, 118 per 100 m2), and Elam (112 per 100 m2) streams, and the lowest density was recorded in the Delichay (downstream, 48 per 100 m2) and Absefid (49 per 100 m2) streams.The distribution and abundance of stream-dwelling salmons are primarily regulated by food and space. The abundance of brown trout on a local scale indicates variety in quality and habitat access for brown trout in the Lar National Park. We speculated that habitat diversity has influenced the density of brown trout in various streams in the region by affecting the abundance of aquatic invertebrates, which are the main source of prey. However, the results of regression (R2= 0.02, p value = 0.72) and correlation (Spearman, r = 0.24) analyses showed no significant relationship between the density of fish and benthic invertebrates in the Lar National Park streams. Despite the enough abundance of prey in the Lar streams, the fish were low in density. The cause of this incongruence is probably related to the salmon fishing in Lar National Park in the past.Comparing fish densities in 2009 and 2017 showed that the trout density in 2017 had a better condition than the trout density in 2009. Considering that in 2014, the Department of Environment stopped issuing fishing licenses in this area, one of the reasons for the increase in fish density is probably a positive effect of the fishing prohibition on this species.Since brown trout abundances in the Lar National Park streams are spatially-temporally variable, it is necessary to provide reasonable management strategies and continuous monitoring to prevent them from global warming and conserve them in the streams of the Lar National Park. Furthermore, due to climate change and being at risk of other populations of brown trout in different habitats in Iran, this population should be protected as a support population.
Original Article
Zohreh Talebi; Seyyed Ali Ayyoubzadeh; Hossein Mostafavi; Mohammad Mehdi Hoseinzadeh; Hossein Shafizadeh
Abstract
ABSTRACTBackground and Purpose: Change is an integral part of all river systems. Most rivers now operate under fundamentally different conditions to those that existed prior to human disturbance. Human interventions indirectly change geomorphic processes such as sediment transport, erosion and sedimentation ...
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ABSTRACTBackground and Purpose: Change is an integral part of all river systems. Most rivers now operate under fundamentally different conditions to those that existed prior to human disturbance. Human interventions indirectly change geomorphic processes such as sediment transport, erosion and sedimentation along the rivers, and the spatial distribution and rate of these processes often including profound changes to river morphology. Therefore, it is important to evaluate the morphological quality, especially for the rivers of Iran, which are characterized by a very high level of human pressure. For this reason, In this research, a morphological evaluation from the upstream to the middle of the Talar River (Northern Iran - Mazandaran) using the Morphological Quality Index (MQI) and with the aim of determining changes in its morphological quality has been considered.Materials and Methods: Talar River was divided into two landscape units, three segments and 23 reaches based on the hierarchical approach and according to the physiographic condition. The evaluation of Talar river has been done after drawing and analyzing the spatial units using Morphological Quality Index (MQI).Results and Discussion: The results obtained from 28 MQI parameters in 23 reaches show that about 15% of the reaches have a "good" condition, almost 35% of the reaches have a "moderate" condition, and more than 50% have a "poor" and "very poor" condition, which means significant damage to the river corridor in the reaches. The subject of investigation and the need to pay attention to the corrective solutions and restoration of the river and its banks. Along the Talar River, due to the large amount of agriculture, urban development and road crossing, the reaches that are in the urban area have poor and very poor morphological quality class, and the reaches that are in the forest area, virgin and untouched, have The morphological quality has been evaluated as good. Also, the results of the evaluation indicate that the average quality class of the investigated reaches is in "moderate" conditions.Conclusion: Considering that the urban and agricultural development and sediment collection takes place in the boundary of the river bed and the vegetation cover and the river corridor have been destroyed in most of the reaches, measures such as observing the boundary of the river bed and boundary as well as planting plants On the river bank and removing sediment based on annual yield will help to restore the river in many reaches. In addition, the results of this evaluation have shown that the MQI morphological quality index method can be a suitable and effective tool in diagnosing hydromorphological challenges. Also, the morphological quality index provides the conditions for evaluating the morphological condition, but it is not enough for the general hydromorphological classification alone, and it should be integrated through the use of a special method to evaluate the changes in the hydrological regime.
Original Article
Maryam saberiyansani; Yousef Rashidi; Seyed Hossein Hashemi
Abstract
AbstractBackground and purpose:Estimating the production of air pollution from mobile and stationary sources is one of the main pillars of air quality management, and considering the performance of cars in different conditions, calculating the number of emissions of pollutants from mobile sources is ...
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AbstractBackground and purpose:Estimating the production of air pollution from mobile and stationary sources is one of the main pillars of air quality management, and considering the performance of cars in different conditions, calculating the number of emissions of pollutants from mobile sources is one of the challenges of compiling the emission list. The international vehicle emission modeling software (IVE) is used in the studies of compiling the country's air pollution emission list.materials and methods:In this research, in order to investigate the deviation of the model values from the reality, a comparison between the IVE model and the emission measurement of domestic passenger cars at 0 km in the ISQI laboratory dynamometer chassis test based on the Euro 4 emission standard and the New European Driving Cycle (NEDC) has been carried out.Results and discussion:Comparison of domestic car dynamometer chassis test emission data for three important gases, NOx, CO, HC, with emission results modeled by IVE model showed different values, except for one case in NOx emission, where the model was equal to the Quick car, so that NOX emission It was in the range of 0.01 to 0.05, and the model showed the number of 0.03, and in the case of CO, it was in the range of 0.26 to 0.96, which the model showed the number of 0.48, and also HC is in the range of 0.03 to 0.08, which the model results are equal to 0.03Conclusion:Based on the comparison of the results, although the IVE model is somewhat close to the reality, but relying on the hypothetical conditions to estimate the amount of passenger car pollutants is unreliable, and the results of the model cannot be considered a correct estimate of the emissions, but by applying appropriate correction coefficients for each The car is usable.key wordsAir pollution, IVE model, motor vehicles, NEDC cycle, dynamotor chassis
Original Article
Alireza shahmohammadi; Hadi Veisi; Korous Khoshbakht; Mohammad Reza Nazari
Abstract
Introduction: Climate and ecosystem changes in coordination with other factors have challenged many basic paradigms of natural resource management. Extensive changes have led to environmental transformations requiring managers to evaluate their management and actions. Ecological transformations are a ...
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Introduction: Climate and ecosystem changes in coordination with other factors have challenged many basic paradigms of natural resource management. Extensive changes have led to environmental transformations requiring managers to evaluate their management and actions. Ecological transformations are a severe type of irreversible change that gradually, and continuously affects community composition and ecosystem functioning. The purpose of this research was to know the correlation between water, energy, and food in Varamin Plain by the method of the mental model and the dynamics of water, energy, and food correlation under political scenarios.Materials and methods: In this research, by using the mental modeling of the beneficiaries of Varamin Plain and university experts, it was done to know the relationships of the model of water, energy, and food nexus. Then, using the systems dynamics model to determine the cause-and-effect relationships between the variables, the variables were quantified. The data relating to the mental model were collected through dialogue and participation with the farmers and managers of the region using the Mental Modeler software. The data relating to the correlation dynamics model was also collected through organizations, regional stakeholders, and authoritative articles and simulated in Vensim software.Results and discussion: The results of system dynamics modeling showed that the state of surface water resources, aquifer volume, and water security of the plain during a period of 20 years would be equal to -158 million cubic meters, 2700 million cubic meters, and -162 million cubic meters respectively; which shows the reduction of resources in comparison with the base situation. The application of scenarios for the allocation of the environmental needs of the Bandalikhan wetland showed that the plain would not have the ecological ability to allocate water to the wetland so in the next 20 years, the water security of the plain will reach -180 million cubic meters. Also, applying the scenario of increasing irrigation efficiency without increasing the cultivated area from 58% to 70% was effective in improving the reduction of agricultural water demand and increasing the cultivated area. The increase in the cultivated area up to 41,600 hectares had a positive effect on agricultural water demand, but more than this amount caused the pressure on water resources to increase.Conclusion: Examining the results and comparing the data showed that during a period of 20 years, the Varamin Plain will have an unfavorable situation regarding water resources and food production. Managing the resources of Varamin Plain requires a change in organizational, agricultural, and development beliefs and values. The development of solar systems in order to meet the energy needs, the establishment of the Varamin sewage treatment plant, and the development of the refinery in the south of Tehran, moving towards sustainable intensification is effective in creating the stability of the resources of the plain in order to properly exploit the resources.
Original Article
Ali Sayyadi; Mohammad Javad Amiri; Mohamad Yazdi
Abstract
Background and purpose: evaporation-transpiration is one of the essential parts of the water cycle balance. Over 0.72% of the country's water resources are unavailable due to evaporation-transpiration. These factors show the importance and necessity of optimal use of water and accurate prediction of ...
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Background and purpose: evaporation-transpiration is one of the essential parts of the water cycle balance. Over 0.72% of the country's water resources are unavailable due to evaporation-transpiration. These factors show the importance and necessity of optimal use of water and accurate prediction of actual evaporation and transpiration in various applications such as agriculture and water resource management, including irrigation planning and plant growth modelling. Accurate evapotranspiration estimates are essential in studies such as climate change, sustainable development and water resources control. This research aims to investigate the process of thermal changes and the rate of evaporation-transpiration of the Tabriz metropolis using remote sensing.Materials and methods: In this research, due to the high accuracy and adaptability of the Sabal algorithm, as well as remote sensing techniques, the Sabal algorithm and Landsat satellite images were used to estimate evaporation and transpiration. For this purpose, Landsat satellite images in sensors ("OLI_TIRS") from 2013-2021 have been prepared from the website of the National Aeronautics and Space Administration (NASA). Also, in this research, the techniques of thermal remote sensing and geographic information system were used, which were combined effectively and efficiently. This study used ARC Gis 8.10 software to prepare the output and Envi 3.5 software to process, analyze and analyze Landsat images.Results and discussion: This research showed that since 2017, the orange and red parts of LST have increased. Pixels with temperatures of 315 to 320 and 320 degrees and above have prevailed in the studied area. The NDVI index showed that yellow and red pixels (0.2-0.4) and (<0.6) have increased. The index (BT) has increased, and 310-315 pixels have been replaced by 320-315 and 320 and above. The evaporation-transpiration results showed an upward trend in evaporation-transpiration, and it increased from 2017 to 2021 in part outside the city centre.Conclusion: According to the results of this research, evaporation-transpiration has increased outside the city centre; in the parts where the temperature increase has been recorded, the rate of evaporation-transpiration has also increased, and a significant relationship has been documented. It is also suggested that according to the results of the research in the years 2017, 2019 and 2021, visible changes have been recorded outside the city centre in evaporation-transpiration to use the daily, monthly and annual formula in future research.
Original Article
َAmin Ghasami; Nasser Mehrdadi; Mohammad Javad Amiri
Abstract
The discharge of urban and industrial wastewater is a phenomenon that occurs in cities and coastal areas. In our country, due to having a long coastal strip and numerous cities and villages adjacent to the sea in the north and south of the country, the discharge of sewage into the sea is an environmental ...
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The discharge of urban and industrial wastewater is a phenomenon that occurs in cities and coastal areas. In our country, due to having a long coastal strip and numerous cities and villages adjacent to the sea in the north and south of the country, the discharge of sewage into the sea is an environmental issue that should be carefully investigated and evaluated.In this research, the MIKE 21 FM numerical model will be used for hydrodynamic simulation and pollution transfer. This model belongs to the Danish Institute of Hydrodynamic Studies (DHI) and is used in engineering fields in the fields of environment, water, coasts and ports. The graphical and user-friendly environment of this model and the extensive capabilities and facilities and assurance of the results and outputs of this model are among its expensive features.The spread of pollution in water environments is an increasing phenomenon. Concern about the environmental and economic consequences caused by the spread of pollution in aquatic environments has forced researchers to conduct a lot of research in this direction and provide models to investigate this phenomenon and predict its effects. One of the methods that can help in predicting and moving pollutants in water environments is numerical modeling.This research included four main sections with different topics. The first issue was the investigation of the treated wastewater from the Bandar Abbas treatment plant, which is discharged into the Gorsuzan estuary. Although, by examining the external features of the discharge area and the resulting bad smell, high turbidity and formation of foam in the water inlet, this issue is evident.Another issue is hydrodynamic and qualitative modeling of the marine environment. For this purpose, two-dimensional Mike model has been chosen. First, hydrodynamic modeling is limited to the entire Persian Gulf. Then, from the results obtained from the calibrated model of the Persian Gulf, the water level data at the border of Bandar Abbas area have been extracted and the local hydrodynamic model has been established. Finally, the qualitative model has been established and implemented based on the discharge location and qualitative data of wastewater discharged into the environment and other available data from sampling and measurements. In this way, the spread of pollution has been investigated.The results show that the discharge of treated sewage into this estuary and even outside the estuary and near the coast will not solve the problems of this area, according to the trials and errors and checking the depth and average speed and direction of currents in the area, the only way The solution is to use atfal with a minimum length of 2000 meters and a depth of about 7 meters. In this case, the possibility of creating eutrophic conditions in the estuary and coastal areas of Bandar Abbas will be greatly reduced due to the discharge of treated wastewater.
Original Article
bahar beishami; SAMANEH ESMAILI
Abstract
One of the challenges faces the world is climate change, due to greenhouse gas emissions. The requirement for preventing this change is development of the renewable energy usage. Among the types of renewable energy, solar energy is considered by many countries around the world, due to its high capacity ...
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One of the challenges faces the world is climate change, due to greenhouse gas emissions. The requirement for preventing this change is development of the renewable energy usage. Among the types of renewable energy, solar energy is considered by many countries around the world, due to its high capacity and availability throughout the year. Regarding the human's long-standing efforts to provide the best temperature for the environment and to save the resources, he has to plan strategies for applying the solar energy, including passive solar systems. Passive solar systems apply the building elements as solutions to use solar energy. Since most of the energy consumed in the building sector is spent on providing thermal comfort, the passive solar systems significantly help to reduce energy consumption; therefore, their usage can be considered an efficient strategy in the process of sustainable development, especially in less developed and rural areas.Many economic planners believe that to realize this form of development, it is necessary to concentrate on the rural tourism infrastructure. Basically, villages are the place for tourists' accommodation and receiving services, i.e. Eco-lodge. Tourism can accelerate this development through the use of solar energy. Applying the renewable energy efficiently in in rural areas, Eco-lodge and generally in the tourism industry is of great importance because of limiting the industry's share in environmental problems, helping to reduce the cost of operating ecotourism resorts, making the business economically attractive, and paving the way for sustainable development.
Original Article
Mohammad Javad Amiri; Hamid Jourkesh; Ahmad Nohegar
Abstract
Introduction: Flood is caused by a sudden increase in the water level of a river due to heavy rainfall, in which excess water flows out of the basin and the riverbed and enters adjacent areas, causing extensive damage to the region's ecosystems and infrastructure. In order to determine and implement ...
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Introduction: Flood is caused by a sudden increase in the water level of a river due to heavy rainfall, in which excess water flows out of the basin and the riverbed and enters adjacent areas, causing extensive damage to the region's ecosystems and infrastructure. In order to determine and implement a strategic plan in the direction of crisis management, understanding the mechanism and development of the flood phenomenon and the amount of runoff created as a result is a priority.Material and methods: In this study, three events of flood on 16 February 2017, 26 March, 2019 and 23 January 2020, when the average rainfall in the Shiraz watershed was 100 mm every three days, were selected and interacted with a synoptic approach. Atmospheric conditions and flood patterns were identified. Next, using by HEC-HMS hydrological model, the amount of rainfall to runoff conversion in each of the sub-basins in the Shiraz watershed was simulated.Results and discussion: The results showed that the maximum precipitation occurs in February and the minimum in July. The maximum annual rainfall is 627 mm in the mountainous areas of Qalat and Golestan and the minimum is 245 mm in Maharloo lake. Synoptic results showed that the establishment of low altitude and cold-water trough at the level of 500 hPa in the eastern Mediterranean along with the establishment of dynamic low pressure system in Iran caused surface air instability in Fars province and by injecting moisture from the Persian Gulf to the massif. The weather has caused floods in Shiraz. The results of rainfall-runoff modeling showed that the highest runoff in Sadra and Qalat sub-basins were 5773 and 5076 thousand m3, respectively, and the maximum peak discharge in Sadra and Qalat was 666 and 389 m3/sec, respectively. It happened at 17:00. The highest volume of rainfall penetration in Qalat and Chenar Rahdar was 5423 and 2546 thousand cubic meters, respectively, and the lowest level of penetration in the Quran Gate was 247 thousand m3, the main reason being the high density of residential-commercial use in this sub-basin.Conclusion: Therefore, it is suggested that in order to manage the flood crisis in Shiraz, controlling runoff produced in northern sub-basins such as Qalat, Golestan and Sadra and increasing the level of permeability can be effective in controlling floods.
Original Article
maryam hasanbigi; Maryam Morovati; peyman karami; mehdi elahi
Abstract
Introduction: Extracting honey from beehives is one of the economic activities for local communities, which is effective in the direct and indirect employment of villagers and as a result, the sustainable development of these areas. Among the pollinating insects, bees play a much more prominent role, ...
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Introduction: Extracting honey from beehives is one of the economic activities for local communities, which is effective in the direct and indirect employment of villagers and as a result, the sustainable development of these areas. Among the pollinating insects, bees play a much more prominent role, and usually the location of the hives can determine the extent of benefit from this ecosystem service. Among the bees of Iran, Carnica hybrid(Apis mellifera meda) has a special place in honey production. Despite the various studies conducted on this hybrid, so far the study has not investigated the suitable conditions for the placement of beehives of this species, so this study seeks to identify the suitable areas for the establishment of beehives as well as the uses/covers that use these services. Awareness of the areas that are prone to beehive placement can be one of the priorities of the planners in the field of agriculture and animal husbandry in Markazi Province.Materials and methods: In this study, in order to model the areas that are susceptible to pollination, among the environmental variables that are somehow effective on the quality and quantity of pollination, In this regard, variables such as spring density, height, topographic humidity, light shade, average spot size, land use/cover, variety of landscape, edge density, distance from agricultural land, average wind speed up to a height of 10 meters, roughness of vegetation and Vegetation density was used. This means that after collecting the points of the hives and pre-processing them, they are ready to do the modeling. Since it is difficult to access all the areas that are not suitable for the establishment of hives in the modeling process, alternative methods such as pseudo-absence methods are used. But identifying suitable areas for recording pseudo-absence points can also justify the analysis with errors. Therefore, first, using the output of presence-only models, pollination desirability was calculated. Then, by subtracting the desirable areas from the entire surface of the land, pseudo-absence points were randomly created in the remaining areas. After the preparation of this group of points, the presence/pseudo-absence models were ready to be implemented. In order to evaluate distribution models, TPR variables and the Kappa index were used. TPR, which is also referred to as sensitivity, is a numerical value that identifies the percentage of presence points that are detected again after applying the presence point threshold. Also, a random forest model was used to calculate the impact of this data set on environmental changes.Results and discussion: The presence-only models in this study were implemented with adequate power. The value of AUC was calculated as 0.89, 0.90 and 0.76 respectively for Bioclim, Domian and single class support vector machine models. The results of the evaluation of the used models showed that all the models have well predicted the presence of beehives in the areas of pseudo-absence of beehives. And the Kappa index for this category of models has been calculated to be at least equal to 0.83. On the other hand, based on the TPR criterion, many of the hive points have been detected again after applying the hive threshold limit, which can indicate the good level of prediction of the used models. Also, the findings showed that the diversity of the landscape has a greater impact on the quality of pollination than the proximity to agricultural lands. And the height of up to 1813 meters above sea level, as well as the wind speed of 3.47 meters per second, are the best conditions for the presence of beehives. Among the different cities of Arak, Farahan, Khandab, Shazand and Khomein have the highest value for pollination.Conclusion: Planning for the protection of natural areas as well as areas prone to the establishment of beehives can be done by emphasizing the location of Arak, Farahan, Khandab, Shazand and Khomein cities. The findings of this study show that the use of species distribution models can be effective for identifying suitable areas for beehive establishment and pollination activity. On the other hand, combining the findings of this group of studies with other spatial data that determine the patterns of the landscape can provide a clear view of the influence of the landscape.
Original Article
Mahmoud Ahmadi; Davood Darvish
Abstract
The change between the surface temperature of the city and its surroundings is the result of changes in land cover. The purpose of this study is spatial analysis and extraction of the trend of urban heat islands in Iranian metropolises in summer in 5 metropolises of Iran including Tehran, Mashhad, Isfahan, ...
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The change between the surface temperature of the city and its surroundings is the result of changes in land cover. The purpose of this study is spatial analysis and extraction of the trend of urban heat islands in Iranian metropolises in summer in 5 metropolises of Iran including Tehran, Mashhad, Isfahan, Shiraz and Karaj. Landsat 7 and 8 satellite imagery from 2003 to 2018 were used to retrieve the surface temperature, the Gates statistic was used for spatial analysis, and the McKendall method was used to analyze the trend. The results show that the average LST in areas built within the city is higher than the average LST in non-urban areas around and even sometimes the city itself and the strongest SUHI in areas such as asphalt surfaces of airport runways, parking lots and galvanized roofs. Occurs.The intensity of SUHI in all metropolitan areas in the city center is not higher than other areas, this example can be seen in Isfahan and Ahvaz where the river passes through the city center. Vegetation and the resulting soil moisture play a major role in Iran's SUHI metropolitan areas, while urban sprawl may reduce daily LST in arid climates. The overall relationship between LST and NDVI for the study period is strong. The inverse relationship peaks in the warmer months of July and August. Park effects as a cooling agent in LST. The average LST of urban areas with large parks has decreased by about 3 ° C in the park area itself and surrounding areas. The LST and SUHI patterns were highly associated with high-density urban areas, while the LST and SUHI patterns were less associated with vegetated lands and water levels, as well as in low-density urban areas. The results of this study on the spatial distribution of surface temperature in 5 metropolitan areas of Iran showed that there is an inverse relationship between building density and surface temperature The surface temperature in the whole metropolis studied has an increasing trend and except for Isfahan, which is not statistically significant at the level of 0.05, this temperature increase is not significant. The slope of the trend for the studied metropolis is higher than 1 degree Celsius, which was more intense in Karaj than other metropolises under study. The minimum slope of the ground surface temperature trend was calculated in Isfahan and the maximum in Karaj.
Original Article
Mostafa Tahani Yazdly; Sayyed Mohammad Hosseini; Farahnaz Khoramabadi; Mohammad Mohtaram
Abstract
IntroductionIn recent decades, along with the physical development of cities and population increase due to immigration, Heat islands, which are mainly the result of human made activities, have gained significant importance. So that; The reduction of vegetation cover, the high consumption of fossil fuels, ...
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IntroductionIn recent decades, along with the physical development of cities and population increase due to immigration, Heat islands, which are mainly the result of human made activities, have gained significant importance. So that; The reduction of vegetation cover, the high consumption of fossil fuels, the emission of greenhouse gases and the use of inappropriate materials in urban construction have created the microclimate of a heat island above the metropolis of the world. Finally, it causes an increase in the land surface temperature, atmospheric stability, persistence and stabilization of pollutants and an increase in respiratory diseases. Today, by using remote sensing methods and using digital satellite images, it is possible to examine the land surface temperature with high accuracy and in a short period using MODIS sensor and Terra satellite images. Therefore, the main objective of the current research is to analyze the temporal and spatial variations of heat islands of Isfahan using the principal component analysis method. With this technique, it is possible to identify the seasons and months when increased the land surface temperature and the heat island.Materials and methodsIn this regard, the present research considers analyzing the temporal and spatial variations of this phenomenon in Isfahan during period of 20 years (from 2000 to 2020 AD). To achieve this purpose, was used the land surface temperature (LST) data extracted by MODIS sensor and Terra satellite. These data are available for the whole world with a time resolution of 8 days and a spatial resolution of 1x1 km in a sinusoidal grid with dimensions of 1200x1200 km. Therefore, for Isfahan, 913 images extracted from the MODIS sensor. Then, with the principal component analysis (PCA) method, the seasons and months that have the most influence on the occurrence of heat islands identified and in order to analyze the trend of this phenomenon, were used the Mann-Kendall test and the Kolmogorov-Smirnov test.Results and discussionThe findings of the research indicate that, the land surface temperature in the last 20 years in Isfahan had an increasing trend with rate of 4%. Although this trend in the population and urban centers has been completely different from the surrounding areas of Isfahan. In terms of spatial distribution, the highest occurrence of heat island in the eastern and southeastern parts (including Hassan Abad and Jolgeh) due to its proximity to the hot deserts of Kavir-Lout, proximity to Sepiddasht, Varzaneh, Shahrak Ramsheh industrial towns and changing in the land use of agricultural to industrial and residential has been registered. also in the North-West region (including Mahmudabad and Isfahan city) due to the increase in man-made heating caused by the increase in the consumption of fossil fuels, the growth of residential, industrial and commercial units, temperature has risen. In addition, the results showed that the intensity of the heat island in winter is more than in summer, and the most intense time of its occurrence recorded in January and the least in November.ConclusionIsfahan is integrally affect by global climate conditions, but depending on the geographical location of each part of this province, the land surface temperature and the occurrence of heat islands are different, so that, eastern and central parts, adjacent to Kavir-Lout and close to industrial towns, have an increasing trend. Moreover, the southern parts have a decreasing rate of temperature and heat islands due to less urban population, larger agricultural lands and more vegetation. The increase in urbanization, migration, and the increase in fossil fuel consumption, the decrease in vegetation, the aggravation of drought, and the change of land use have a fundamental role in increasing the occurrence of this phenomenon.
Original Article
Sepehr Akhlaghifard; Toraj Nasr Abadi; Hassan Hoveidi
Abstract
Introduction: Rivers are considered as a vital resource for mankind from the past to the present day.Considering the ever-increasing population, industrial developments and the expansion of modern urban societies, it is expected that the rivers located near densely populated urban and rural areas to ...
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Introduction: Rivers are considered as a vital resource for mankind from the past to the present day.Considering the ever-increasing population, industrial developments and the expansion of modern urban societies, it is expected that the rivers located near densely populated urban and rural areas to be in danger of destruction due to a large part of urban, rural, domestic, industrial and agricultural pollutants to the sources of surface and ground water in the riparian and riverside more than any other water ecosystems. On the other hand, regarding Iran's arid and semi-arid climate, the use of sediment qualitative indicators in research and investigation is crucial in order to predict, evaluate and provide a sustainable solution for controlling the amount of pollutants and also improving the quality of river water.Material and Methods: The Karaj River is one of the main freshwater and energy production resources in the region, which plays a vital part in creating an ecological balance in parameters affecting the quality of this water ecosystem. The purpose of this research is to measure the concentration of heavy metals in the sediments of the river bed and to evaluate and analyze it using Geoaccumulation index and Enrichment Factor, which led to the suggested solutions in order to avert and control the further spreading of pollution. In this research, nine stations were selected in consideration of land use of the area and the sediments of the river bed in each station were sampled. Sediment samples were prepared and later transferred to the laboratory and the total concentration of heavy metals was measured by Inductively Coupled Plasma Mass Spectroscopy (ICP) device.Results and Discussion: This research was carried out in order to investigate the concentration of heavy elements in the sediments of the Karaj River bed as a suitable indicator to evaluate the water pollution and theriver system by using Geoaccumulation index and Enrichment Factor in the area of the Salt Lake catchment area. The results obtained from the measurements using the mentioned indices assessed that the level of heavy elements pollution is relatively low the Karaj River. Nevertheless, part of this slight pollution is related to human activities such as road construction, tourism and the leakage of local runoff and sewage into the river and its riparian zone, which led to the increase of the Geoaccumulation of elements including copper and chromium to the numbers of 1.01 and 1.96 in downstream stations P8 and P9 respectively. Also, the highest average amount of Geoaccumulation for Copper in 9 sampling stations was 0.23. On the other hand, these man-made activities have significantly increased the arsenic Enrichment up to 17.81 in station P4 and the average Enrichment Factor of Arsenic in 9 sampling stations up to 13.12. But since each heavy element has its own unique nature, part of the quantity of the pollution present in the sedimentary environment of the river is related to natural factors, geology, soil erosion and weathering of riverbed rocks.Conclusion: The process of changes in the amount and distribution of elements in the sediments were compared and the factors affecting their alignment or mismatch were discussed and researched. Generally, the results of this research show that the Karaj River, taking into account the Geoaccumulation index and Enrichment Factor, has negligible contamination of heavy metals in the riverbed sediment. But the trend of index changes along the river route shows the direct effects of destructive human activities in the region.
علمی - پژوهشی
Khadijeh Asghari; Hamid Jalilvand; Hamed Asadi
Abstract
AbstractBackground and purpose: Soil is the largest source of carbon in the biosphere and more than half of its carbon is stored in forest ecosystems. Considering the importance of soil carbon part, the purpose of this research is to investigate how different species of broadleaf and coniferous species ...
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AbstractBackground and purpose: Soil is the largest source of carbon in the biosphere and more than half of its carbon is stored in forest ecosystems. Considering the importance of soil carbon part, the purpose of this research is to investigate how different species of broadleaf and coniferous species affect forest carbon storage in soil, considering their different ability to store and use soil nutrients in The forest is Kolet.Materials and methods: In this research, first, three stands of Acer velutinum Boiss, Alnus subcordata C.A.M, and Cupressus sempervirens var horizontalis and one natural forest stand were selected in the study area. Ten samples of 400 square meters (2020 meters) were selected in each cluster. Also, soil samples were collected from the four corners and the center of each plot from a depth of 0-15 cm; Then the soils are mixed together and a combined sample is separated for the laboratory (40 samples in total) which is used to study the physical and chemical characteristics of the soil (bulk density, soil texture, soil reaction, electrical conductivity, organic carbon, total nitrogen, phosphorus and absorbable potassium) was transferred to the laboratory. SAS statistical software was used for soil data analysis related variables, and the Vegan R software package was used for principal component analysis (PCA) to identify the most significant factor and differentiate between the studied populations. Results and discussion: Based on the obtained results, soil reaction rate, absorbable potassium, relative humidity, organic carbon, clay and soil carbon storage had significant differences among the four stands (P < 0.01). Alnus subcordata and Acer velutinum showed the highest amount of carbon storage compared to Cupressus sempervirens and natural forest stand. The difference observed in the amount of soil organic carbon in the studied stands depended on the different capabilities of tree species in restoring the soil ecosystem. The planting of broadleaf species resulted in more carbon storage in the short term than coniferous species, because broadleaf tree species increase litter production and nutrient return, making them more effective in restoring degraded forest soils. And this is due to faster leaf decomposition, higher nitrogen content and lower C/N ratio, while the presence of resinous and phenolic substances in coniferous leaves negatively affects their decomposition of their litter.Conclusion: In summary, this research showed that reforestation with broadleaf species in various areas of the region significantly impacted the soil carbon stock and carbon storage potential based on the type of tree species. Particularly, broadleaf species such as Alnus subcordata and Acer velutinum played a crucial role in increasing the amount of carbon stored in the soil of the studied region.
Original Article
Shahin Kordi Torshabi; Parvin Sadeghi; Zahra Taghizadeh Rahmat Abadi
Abstract
Introduction: The abundance and durability of plastic wastes in the environment, especially in the marine environment, comes with extensive environmental threats to the ocean and its biodiversity. Microplastic (MP; 1 µm to 5 mm) is an important component of marine plastic pollution. The concerns ...
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Introduction: The abundance and durability of plastic wastes in the environment, especially in the marine environment, comes with extensive environmental threats to the ocean and its biodiversity. Microplastic (MP; 1 µm to 5 mm) is an important component of marine plastic pollution. The concerns about the negative effects of MPs on human health have raised attention to the presence and physiochemical properties of MPs found in aquatic environments and inside body of edible aquatic animals. Therefore, the main goal of this study is to investigate the quantity (presence, abundance, and size), and quality (shape and color) of MPs found in the digestive tract of Blackfin barracuda (Sphyraena genie) living in the Oman Sea.Materials and methods: For this study, 27 pieces of S. genie (average total length: 42.5 cm ± 5.36 and total weight: 353.5 g ± 2.5) were collected from the northern shores of the Oman Sea during the winter of 2020 by gill nets. The fish were bioassayed and then dissected in the laboratory. To extract MPs, each digestive tract was digested with a 10% KOH solution and then vacuum filtered. Identification, counting, and determination of the characteristics of MPs (shape, size, and color) were done by a stereomicroscope. Particle dimensions (μm) were measured using ImageJ software. Results and discussion: All the examined fish had MPs in their digestive tracts (100%). 285 MPs were found in the S. genie samples. The MP average abundance was 10.5 ± 5.19 particles per individual and 0.8 ± 0.2 particles per gram of wet weight. The most identified microplastics were in the form of fiber (abundance: 73%), irregular fragments (26%), and films (1%). The MP colors ranged from light to dark color spectrum. The color combination according to abundance was black > gray > transparent > creamy > red > blue and dark red > green and brown > pink and white > dark blue, and peach. Around half of the MPs were shorter than 300 µm in length, while only about 9% of the MPs were longer than 1 mm. In terms of size, microplastics were classified into eight groups: category one (size: 1 - 100 µm; N: 64 MPs), category two (100 - 300 µm; N: 85 MPs), category three (300 - 500 µm; N: 45 MPs), category four (500 µm - 1 mm-; N: 66 MPs) category five (1 - 2 mm; N: 19 MPs), category six (2 - 3 mm; N: 5 MPs), category seven (3 - 4 mm; N: 1 MP) and category eight (4-5 mm; No MP). The size of the irregular fragments was smaller than the fibers, mostly less than 100 µm. Considering the shape and small size of dominant MPs, the presence of small fish remains (skulls, scales, and gill fibers) and shell fragments in the digestive tracts, and also the carnivorous diet of the S. genie, it can be assumed that these degraded secondary MPs might have been transferred through the food chain.Conclusion: Microplastics were observed in the digestive tracts of all the examined samples of S. genie. The isolated MPs were in the form of fibers, irregular fragments and films. Black, gray, and transparent colors were evident as the dominant colors, and fiber was the dominant shape in microplastics. MPs smaller than 1 mm were the most abundant particle (92%), too. The presence of microplastics in the studied fish lead to ecological and health concerns. Therefore, it is necessary to raise public awareness and manage the entry of plastic pollutants into the marine environment.
Original Article
Behnaz Naderi; Afshin Qishlaqi
Abstract
Introduction: Soil contamination with potentially toxic metals is one of the most critical challenges in terms of food and human health safety. Majority of the studies on the metal pollution of agricultural soils have been carried out by analyzing the total concentration of metals in the soils whereas ...
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Introduction: Soil contamination with potentially toxic metals is one of the most critical challenges in terms of food and human health safety. Majority of the studies on the metal pollution of agricultural soils have been carried out by analyzing the total concentration of metals in the soils whereas the metals are present in different chemical forms or species in soils, that it should be considered in a full-fledged environmental assessment. The purpose of this research is to assess the total concentrations, pollution level, source and speciation of potentially toxic metals in agricultural soils of Jovin plain in Razavi Khorasan province.Materials and methods: 27 soil samples were randomly collected from the entire plain at a depth of about 50 cm. Soil physicochemical parameters (organic matter, pH, carbonate content, soil texture) along with the total concentrations of potentially toxic metals (zinc, cadmium, arsenic, chromium and nickel) were measured by means of standard methods. The level of soil metal pollution was assessed by calculating pollution indices (enrichment coefficient, land accumulation, pollution load index) and their possible origins were apportioned by multivariate statistical methods (correlation and principal component analysis). The modified four-step BCR method was used to determine the species or chemical phases of metals in soil samples. Results and discussion: it was found that the cultivated soils are alkaline in nature content, clay loam in texture and moderate in terms of organic matter content. In majority of the soil samples, the concentration of all studied metals is higher than the mean crust and the world mean soils. Evaluating the level of soil metal pollution also showed that the soils are moderately to heavily contaminated in terms of chromium, nickel and copper and heavily contaminated in terms of arsenic and zinc. The results of the multivariate statistical analysis revealed that chromium and nickel are mainly of geogenic sources attributable to the ophiolite rocks in the region while zinc, cadmium, copper and arsenic are mainly derived from anthropogenic sources i.e., agricultural activities in the study are. Based on speciation analysis studies, chromium and nickel are mainly extracted from the residual phase (F4), zinc and copper from the oxidizable phase (F3), and arsenic from the reducible phase (F2) and cadmium was mainly retrieved from the soluble/exchangeable phase (F1). The high extraction percentage of chromium and nickel from the residual (stable) phase indicates that the source of these metals in the soils is mostly geogenic with very limited mobility and bioavailability. On the other hand, the high percentage of metals such as zinc, copper, cadmium and arsenic retrieved from the first three phases (F1+F2+F3) reveals that they are mainly from anthropogenic sources having high mobility and bioavailability in soil samples.Conclusion: Based on the assessment made in this research, it was found that the metals in the agricultural soils of Jovin plain have surpassed their standard guideline limits and apart from chromium and nickel, the other studied metals have been derived from anthropogenic sources (agricultural activities) in the study area. The chemical speciation analysis also showed that the metals in the soils occurred in different chemical forms or phases depending on their different origin and pollution level, which in turn leading to the different mobility and bioavailability of these metals in the soil samples.
Original Article
Reyhane Dehghan; Khosro Piri; Asghar Abdoli
Abstract
Background and purpose: The purpose of this study is to investigate endotoxin contamination by separating total endotoxin, free endotoxin, and attached particles from the source of the Jajrud River to the Letian dam and the water inlet of this dam to the treatment plant to the outlet and treated water ...
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Background and purpose: The purpose of this study is to investigate endotoxin contamination by separating total endotoxin, free endotoxin, and attached particles from the source of the Jajrud River to the Letian dam and the water inlet of this dam to the treatment plant to the outlet and treated water to identify the source and fate of the types Endotoxin is the identification of the key and critical points of this emerging pollutant along the Jajroud river route, as well as the effect of the implementation of purification processes to reduce the endotoxin produced at each stage and ensure the low level of endotoxin in the outgoing drinking water; to identify and manage the key and critical points of endotoxin activity based on that.Materials and methods: Sampling in the autumn season of 1401 along the Jajroud River, taking into account the effect of human activities, the entry of sewage into the river, the water depth, and the course of the river from Ab Nik stations, between Ab Nik and Fashm, Fashm, Between Fashm and Lavasan, Lavasan, Letian dam lake, the water outlet after the dam lake and Saeed Abad, as well as the inlet water of Letian dam, to the treatment plant from incoming raw water, chlorinated incoming water, separation water, filters, rapid mixing and Finally, the water was discharged from the treatment plant. Dark glass bottles were used for sampling. The samples were kept cool and immediately transferred to the laboratory. The physical and chemical properties of the sampled water were first measured to measure the activity of endotoxin. Then, the LAL kit (Kinetic-Chromogeni LaL kit, Bioendo ™ KC0828) was used to measure endotoxin by separating total, free, and bound endotoxin.Results: This research showed that the level of endotoxin activity in Jajrud River water differed in different sampling stations. The amount of total endotoxin varied between 53 and 85 Eu/ml. Free endotoxin and endotoxin bound to particles had different values in other stations. The highest amount of free endotoxin attached to particles was observed in the outlet stations of Letyan Dam Lake and Letyan Dam Lake, respectively. The activity of total endotoxin, free and bound to endotoxin, was also variable during the purification process. The amount of total endotoxin during different processes was observed between 0.6 and 9.4 Eu/ml. The highest activity of free endotoxin was observed in the water of sedimentation filters, while the activity of endotoxin bound to particles in rapid mixing water was higher than in other samples. Also, the chlorination process is a critical process that plays an important role in the amount of endotoxin activity both during the treatment process and in the water leaving the treatment plant. Because during this process, the composition of the microbial community will change, and thus, by reducing or increasing Gram-negative bacteria, it can increase or decrease endotoxin. Also, the amount of free chlorine in purified water is one of the essential things that can affect the amount of endotoxin after leaving the treatment plant. On the other hand, chlorination causes lyses, which can increase free endotoxin bound to particles. According to the results, among the key stations along the Jajrud River are the stations close to the residential areas, which include Fasham and Lavasan because these areas, due to the high level of pollution they have, provide a suitable environment for the microbial community and They create gram-negative bacteria.Conclusion: It is suggested to carry out more in-depth studies on the difference in microbial communities along the Jajrud River and to determine the relative level of gram-negative bacteria, especially in critical points with more pollution.
Original Article
Majid Beheshti; Ahmadreza Mehrabian; Farzaneh Khajoei Nasab; Mohammad Reza Fazlollahi
Abstract
Tehran is one of the metropolises of Asia as well the world that needs careful ecological assessments as well management planning. Providing a pollen database is one of the important measures in order to manage the environment of this city. This database is the primary step of the Pollen Atlas of Iran ...
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Tehran is one of the metropolises of Asia as well the world that needs careful ecological assessments as well management planning. Providing a pollen database is one of the important measures in order to manage the environment of this city. This database is the primary step of the Pollen Atlas of Iran as well pollen calendar, the management of asthma and allergies, as well as archaeological studies in Tehran. Up to now little attention paid to this scope, so it seems to be necessary to preparation the mentioned data base. Plant samples of this study were collected from parks and various urban green spaces of Tehran. As well deposited in the herbarium of Shahid Beheshti University (HSBU). These specimens were identified using scientific sources as well valid flora such as Flora of Iran, Flora Iranica and etc. The pollen grains were photographed using Scanning Electron Microscopy (SEM). The 12-20 pollen grains were evaluated using Image Tools 3.6 software to evaluate quantitative morphological traits. Finally, a comprehensive description of the quantitative and qualitative morphological traits of pollen grains was prepared. In this study, pollen grains of 92 species belonging to 42 trees and herbaceous plant genera were studied. The Asteraceae with 11 species has the highest number of species in this study. The pollen grains including monad (91) tetrad (1). Also 70 species are isopolar and 22 species are heteropolar. Sculpturing including 16 different types. This study is the first illustrated pollen data base on Tehran that is an important reference to history of agriculture and archeology in the region. The data of this study showing several species in Tehran have been planted regardless of their allergic effects, so, it should be considered in the expansion of green space.
Original Article
Houshang Moradi; Saeed Maleki; Saeid Amanpour
Abstract
achieving urban water security is a major challenge for many countries. urban water security has created significant concern for urbanization and climate change. Having systems thinking and integrated management can help to understand the mechanisms that affect the long-term water security of a city. ...
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achieving urban water security is a major challenge for many countries. urban water security has created significant concern for urbanization and climate change. Having systems thinking and integrated management can help to understand the mechanisms that affect the long-term water security of a city. Today, the metropolis of Ahvaz has become one of the largest cities in Iran due to the development of economic, social, cultural, and political activities with the growing population. Considering that the process of urban construction and development and excessive population growth in this metropolis was not subject to a pre-determined and codified plan and its water supply and distribution plans were not consistent with the increase in population; Therefore, in this city, like all the big cities of Iran and the world, there are various problems in terms of water security. Global climate change, geographical features of this metropolis, environmental issues, pollution of water resources and insufficient water resources for the current population on the one hand and the other hand the increasing industrial use of water, the existence of large industries, and new and growing cities and towns around this The metropolis as well as the huge consumption of water in the agricultural lands around the city of Ahvaz has made the water resources more limited. The continuation of this trend is all reason for the need for comprehensive planning and assessment of water security for the future. to analyze the trend of changes in climatic parameters of precipitation and discharge of Ahvaz station, the period of 70 years ( 1330 - 1400 ) was studied And the time trend of changes in the aforementioned climatic parameters was calculated using the Menkendall non-parametric test in the monthly, seasonal and annual time series during the statistical period of the study. The results showed that during the studied period of the year, there have been changes in climatic parameters in the city of Ahvaz in the form of a decrease in precipitation and a decrease in discharge, and this has had consequences for the metropolis of Ahvaz. This study presents a systematic approach to better understanding urban water security, with a working definition and an assessment framework for application in urban areas. The assessment framework for achieving urban water security depends on four main dimensions: Drinking water and humans, ecosystem, climate changes, and risks related to water and socio-economic factors. This framework allows further analysis of the relationships and trade-offs between urbanization and water security, as well as between the aforementioned indicators. Applying this framework will help governments, policymakers, and water stakeholders target scarce resources more effectively and sustainably. This study shows that achieving urban water security requires a comprehensive and integrated approach with common stakeholders to provide a meaningful way to improve the management and understanding of urban water security.
Original Article
Mansour Chatrenour; Nasrin Moradimajd; Mir Naser Navidi; Naser Davatgar
Abstract
Introduction: One of the consequences of the climate change phenomenon in Khuzestan province is the drying up of a large part of the wetlands of this province, including Miangaran and Hoor al-Azim, which has caused dust storms due to their continued drying in recent years. In this regard, this research ...
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Introduction: One of the consequences of the climate change phenomenon in Khuzestan province is the drying up of a large part of the wetlands of this province, including Miangaran and Hoor al-Azim, which has caused dust storms due to their continued drying in recent years. In this regard, this research aims to predict climate changes in the area of Miangaran and Hoor al-Azim wetlands by SDSM statistical microscale model based on HadCM3 B2 and A2 climate scenarios. Considering the specific conditions of the region and the fact that few studies have been done regarding temperature change in these areas, knowing the state of temperature change can help better management of resources, especially water resources management.Materials and methods: These parameters include the average sea level pressure, the geopotential height of the surface of 850 hectopascals and the average temperature at a height of two meters. For this purpose, by using the daily data of average temperature, minimum and maximum temperature in the synoptic stations of Izeh and Bostan as the closest stations to Hoor al-Azim and Miangaran wetlands in the periods of 2010-2039, 2040-2069 and 2070-2099, predictions were made and Then a comparison was made with the base period (1961-1990). To check the performance of the models and compare them, two drawing methods were used conventional statistical criteria of PBISE, NSE, MAE, RMSE and R2.Results and discussion: The results of the simulation of the HadCM3 model along with observational data for the Izeh station, modeled annual average temperature data was 18.47°C and for the Bostan station, modeled annual data average temperature was 19.10°C. As can be seen, both stations had a higher average temperature in the base period, and the maximum temperature in the Miangaran wetland is much higher than Hoor al-Azim wetland in the base period. The minimum temperature results show that the difference between two stations is small and minor. The results showed that in both stations in scenario A2, the average temperature had significant cycles with return periods of 1.2 years and the lowest significant cycles for the two stations were in return periods of 2.3 and 1.3 years, respectively. In scenario B2, the average temperature in two stations has significant cycles with return periods of 7.5 years and the lowest significant cycle with return period of 1.2 years. The results of examining the cycles in the studied areas indicate that in the A2 scenario, certain climatic conditions in the area have short-term return periods. In two stations in scenario B2, in the upper percentile of the significance cycle, the mean temperature is at the confidence level (97.5%) in the 30-year return period, and in the lower percentile of the significance cycle, the mean temperature is at the confidence level (2.5%) in the return period. 1 year was obtained in both scenarios, which indicates a wider range of the return period and a higher probability of extreme temperature events in the B2 scenario. In the comparison of the two stations, it can be seen that in scenario A2, the average temperature of the Miangaran wetland is 1.02 °C and Hoor al-Azim wetland is 1.08 °C. In scenario A2, Miangaran wetland has a higher average and maximum temperature, while Hoor al-Azim wetland has a higher minimum temperature increase. While in scenario B2, the average temperature of Miangaran lagoon is 1.47 °C and Hoor al-Azim wetland is 5.12 °C.Conclusion: The results of the data analysis in the future observation and simulation periods with scenarios B2 and A2 show an increase in the mean, minimum, and maximum average temperature in the future simulation periods compared to the base period in Izeh and Bostan stations so in Bostan station, the average minimum and maximum annual temperature also increased in the third period compared to the base period. And in both scenarios, due to the increase in temperature, the drying process of both wetlands will continue.
Original Article
Sajjad Zarei; Hassan Mahmoudzadeh; Firouz Jafari
Abstract
Extended AbstractIntroductionWith the progress of science and technology, the development and growth of cities and expansion in nature has led to the destruction of the environment and the creation of various biological pollution in human societies. One of the most obvious pollutions that affects the ...
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Extended AbstractIntroductionWith the progress of science and technology, the development and growth of cities and expansion in nature has led to the destruction of the environment and the creation of various biological pollution in human societies. One of the most obvious pollutions that affects the comfort of urban residents and has a direct relationship with the mental health of people in the community is noise pollution, which can cause mental illnesses, irritability, allergies, and other neurological and mental illnesses. to be In this article, the evaluation of the noise landscape of the 4th district of Tabriz metropolis is the aim of the research, and the amount of noise pollution during the peak activity hours of the 4th district of Tabriz metropolis and the effect of social, physical and environmental variables on the urban environment have been investigated.Materials and methodsIn terms of research method, this article is a combination of descriptive-analytical, documentary and survey methods. District 4 of Tabriz metropolis was divided according to the standard square grid method (mentioned in ISO1996 standard) with squares of 200×200 meters and the center of each square was identified as a sound sampling station. The equivalent continuous sound level(Leq) was measured in each station for 3 minutes, in the morning from 8 to 11 in the morning and in the evening from 19 to 22 at night in the months of Tir to Azar 1400(July to December 2021). Sound recording was done using a decibel meter (Benetech digital sound meter model GM1357) with the sound pressure level of network A with fast response speed. The dependent variables of this research are the equivalent continuous sound level(Leq) in two time periods, morning and evening, and independent social and physical variables in this research, population density, building density, distance from road, distance from office, distance from educational, distance from urban facilities, distance from commercial, distance from Therapeutic, distance from industrial, distance from wastelands, distance from green space and distance from air corridor were selected. The drawing of each of the maps related to dependent and independent variables of district 4 was done separately in the GIS software environment, and then the effect of each of the independent variables on the dependent variables was evaluated using a linear regression model in SPSS software.Results and Discussion The obtained results show that the sound landscape of district 4 of the metropolis of Tabriz is the noise of children playing, the noise caused by the passage of vehicles and motorcycles, garbage trucks when loading trash cans, and the noise of construction workers at the neighborhood level. The result of the horn of a motorcycle and the noise of its turn and the passing of trucks and trucks and motor vehicles on the level of the streets and main axes and the traffic noise and the horn of intercity buses, cargo vehicles, trucks and international trolleys in the axes 1st grade arterial road (Pasdaran highway and Sento road). Also, Pasdaran, Razvanshahr, Enghelab(42 meters), Yekeh Dekan, Koshtargah, Sharbatzadeh, Shalchilar, Qara Aghaj and Koche Bagh neighborhoods have high noise pollution and the neighborhoods of Hokm Abad, Amo Zainuddin, Jamshid Abad and Shahid Beheshti have less noise pollution.ConclusionIn general, district 4 has more noise pollution in the evening time period than in the morning time period. At the end, solutions to reduce noise pollution in the area are suggested.AcknowledgementThanks to the support fund for researchers and technologists of the presidential vice president for science and technology, who provided material support for this project in the form of a doctoral dissertation.
Original Article
Parisa Kahrari; Shahriar Khaledi; Ghasem Keikhosravi; Seyed Jalil Alavi
Abstract
Introduction: The rapid increase in population, growth of urbanization and industrialization in recent years, which is generally associated with an increase in demand and energy consumption, and as a result, an increase in pollutant emission sources, has exacerbated air pollution as one of the biggest ...
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Introduction: The rapid increase in population, growth of urbanization and industrialization in recent years, which is generally associated with an increase in demand and energy consumption, and as a result, an increase in pollutant emission sources, has exacerbated air pollution as one of the biggest current crises of urban societies and consequently health risks and related social inequalities in terms of time and space. On the other hand, meteorological parameters directly affect the amount of pollutants as well as the duration of their presence in the atmosphere, and the present research was conducted in order to investigate this effect and discover the relationships between criteria air pollutants and atmospheric elements.Materials and Methods: Besides investigating the status of meteorological elements (temperature, precipitation, wind speed, relative humidity, radiation, sunshine hours and cloudiness) and criteria air pollutants (carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3) and particulate matters with aerodynamic diameters less than 10 microns and 2.5 microns (PM10 and PM2.5)) in Tabriz city during 2004-2021, the present study has explored the relationships between pollutants and meteorological parameters in monthly and seasonal time scales using Pearson's correlation test at the 95% confidence level and the effect of these elements on the concentration of pollutants using Multiple Linear Regression (MLR) and Generalized Additive Model (GAM) in R 4.3.1 statistical software.Results and Discussion: Based on the results of Pearson correlation analysis, NO2 and PM2.5, SO2 and PM2.5 pollutants and PM2.5 and PM10 pollutants have shown significant positive correlation in pairs, so it seems that these pollutants have similar emission sources. Also, the results of this research demonstrate that the concentration of criteria air pollutants in Tabriz was affected by weather conditions during the entire statistical period in the monthly and seasonal time scales and NO2 and PM2.5 pollutants have the most negative monthly correlation with the parameters of temperature, wind speed and sunshine hours and the most positive correlation with relative humidity; PM2.5 has the most positive correlation with pressure; CO and SO2 have the most negative correlation with radiation; O3 has a strong positive correlation with temperature, wind speed and sunny hours and the most negative correlation with pressure, relative humidity and cloudiness; and NO2 and PM10 pollutants have the most positive correlation with cloudiness. The results of fitting Multiple Linear Regression (MLR) and Generalized Additive Model (GAM) for each criteria air pollutant in Tabriz city indicate the better performance of GAM in analyzing the relationships between all air pollutants and the set of independent variables except NO2.Conclusion: The results of this research indicate that the effect of atmospheric elements on the concentration of criteria pollutants in Tabriz city is different depending on the type of pollutant and at different times, and it can be acknowledged that the effect of a specific meteorological parameter on air pollution is uncertain. However, wind speed, radiation, temperature and air pressure are the most important meteorological elements related to the concentration of pollutants in Tabriz city. Also, the consequences of the research suggest that both MLR and GAM can describe the variability of the response variable by a set of predictor variables and explain the linear and non-linear relationships between them. However, considering the non-linear relationship between the concentration of atmospheric pollutants and meteorological elements, GAM is able to justify a higher percentage of changes in all criteria atmospheric pollutants except NO2.
