نشریه علوم و تکنولوژی محیط زیست
سال بیست و سوم شماره 3 (پیاپی 106، خرداد 1400)

In order to identify different types of forest stands, present research was carried out in Ile Goran forest located in Kermanshah province with an area of 430 ha.

The number of 84 square sampling plots with the area of 1600 m2 by random-systematic sampling mehod and random starting point were established in the study area. Woody species and its origin (high forest or coppice) were observed and recorded in the plots. Based on species composition and species origin, forest type classification was done. First, the map of physiographical unit (elevation, slope, aspect) and landform units were prepared in GIS environment.

 The results showed that high forest types (including Quercus brantii and Quercus brantii – Pistacia atlantica type seed) have a narrower range of expansion in terms of altitude than other types. Quercus brantii as an indicator species, the species has wide range of elevation. In terms of land slope, Quercus brantii – Pistacia, either high forest of coppice, have a wider range of propagation than other types and is observed in gentle slopes up to 50% slope.

The results of this study can be used by experts and planners and help to improve the Zagros forests management.

Urban spaces are the environment of human life and its activities. Crimes are committed as a destructive social phenomenon by man in these spaces. Among the major problems in urban spaces that affect the quality of life and the sense of security of citizens is the occurrence of urban crime, and factors such as urban planning, design, sprawl and social –economics, play an effective role in its occurrence or deterrence. Kianpars neighborhood can always face dangers like urban crime, depending on its location.

This article is a descriptive-analytic one. In the descriptive section, statistics and information extracted from the Statistical Yearbook, the supreme court of the Khuzestan and police department of the study area were used. Finally, for analyzing the data, GIS and SPSS softwares have been used to analyze the relationship between the two factors of crime incidence and brightness levels Within the Kianpars area.

Investigations show that criminals act reasonably well in choosing the time and place of the crime and select the most appropriate and least risky locations and areas that are poorly lit for criminal activity and there is an inverse relationship between crime and light.

Overall results show that out of 275 crimes in public and private spaces, 200 cases occurred in the optical range No.1 with the least amount of light and 19 cases occurred in the optical range No.4 with the highest brightness, indicating a significant and inverse relationship between the amount of light and the crime number, as well as studies show that poor lighting in Kianpars has led to a decrease in security and incidence of some urban crime, and overall the lighting system in the study area has been assessed as inefficient and inconsistent with the CPTED principles.

In this study, the characteristics of particles deposited on the surface of the leaves of species of Platanus orientalis, Ulmus carpinifolia, Robinia pseudacasia, Morus alba, and Fraxinus excelsior in the sideline of one of the crowded streets of Tehran (around Azadi Square) were investigated using scanning electron microscopy(SEM)and energy dispersive X-ray analysis.

A base was selected from each tree species. The tree bases were safe and next to each other on the sideline of a high-traffic street. The canopy of the trees was separated from each other. Healthy leaves were placed from a height of 2 to 2.5 meters above the ground surface from the outermost part of the canopy of trees on the street side. Samples were prepared in the laboratory for imaging with electron microscopy of the surfaces of leaves. More than 50 particles were investigated by elemental detector analysis. The mass percentage of the elements of each particle was recorded. The equivalent diameter for each particle that its image had been prepared by SEM-EDX was measured manually in ImageJ software. The leaves were prepared using an image scanner in Jpg format and the area of ​​the leaves was determined by Image J software. The weight of the particles sequestrated on the leaves of each tree was also weighed.

the weight of deposited particles was measured and the leaves' capability of different species of tress to deposit particles was compared. This study is one of the few ones on elemental analysis of individual particles in Iran and it is the first time that the deposited particles on the leaves of trees are studied through this method. Twenty-one elements were detected in particles. Carbon, Oxygen, Iron, and Silica had the highest mass frequency and Carbon, Calcium, Silica, Oxygen, Iron and Potassium had the highest percentage of presence in particles. Particles less than 2.5 micrometers in diameter were the most abundant ones. Metal particles with a diameter between 2.5 to10 micrometers were the most abundant metal particles that were observed. The mean comparison of the diameter of deposited particles on the leaves of tress showed no significant difference between them. Particles' diameter was higher in Platanus orientalis, Morus alba, Fraxinus excelsior, Robinia pseudacasia and Ulmus carpinifolia, respectively. The highest rate of deposited particles on the leaf surface belonged to Platanus orientalis, Ulmus carpinifolia, Fraxinus excelsior, Robinia pseudacasia and Morus alba, respectively.

Leaf area, cracks, leaf surface roughness, wax, veins, and leaf shape have an effective role in changing the properties of deposited particles on the surface of the trees' leaves.

Rate of pollution and so, different concerns about environmental effects of doing a project is becoming the main issue that capital cities increasingly are facing it. So, the purpose of this study was to assess and analyze the effects of strategic management on pollution reduction of oil refining processes in great Tehran area.

The present study is considered as a practical, descriptive and case study. The statistical population was managers of Tehran Oil Refinery (40 people) which were chosen by cluster sampling. Data was collected using a high reliability integrated questionnaire (Cronbach’s alpha = more than 0.85) which was based on Delphi method and helped to identify and weigh the strengths, weaknesses, opportunities and threats by SWOT. In the last analysis Friedman test used to determine the significance of each item. The best strategy was determined using QSPM (Quantitative Strategic Planning Matrix).

The findings indicated that "the strategic plan in the refinery to reduce the pollution from oil refining processes in Tehran refinery," "occupational diseases due to the lack of appropriate protective equipment for workers," "Future development plans to reduce pollution of refinery processes ", " Destruction of vegetation and land degradation” can be ranked respectively as Strengths, weaknesses, opportunities, and threats of pollution reduction caused by oil refining processes.

Many environmental threats, resource degradation and pollution result in incompatible activities.  Besides, as oil industry development is so important and reduction of environmental pollution is crucial too, it is necessary that oil managers make policies and take steps to protect environment, expand and develop the petroleum industry.  The findings indicated that following strategies play a key role in reducing the pollution of oil refining processes:1- Justify the oil industry officials about the importance of the Protection of environment by holding meetings and also enhancement of oil industry and environment organizations.2- Training and improvement of technical knowledge of refinery’s employees about reducing oil pollutions.3- Identifying and preventing some actions of oil refining processes that have negative effects on vegetation, environment and ecosystem.

In recent decades, atriums have been installed in public buildings to optimize energy consumption and provide thermal comfort, and therefore have always been of interest to mechanical engineers, architects and designers. Atrium also created different microclimates with different thermal layers in its lower space, which affected the cooling load and thermal comfort inside the building.Therefore,the purpose of this research, is to find the most suitable form and height of atrium for reducing energy consumption and heat stratification in commercial buildings of Mashhad city with cold and dry climate.

This research has used fluent software and Mathematical equations. Initially, Almase Shargh commercial building in Mashhad with central atrium in a spherical form of 5 m height was selected and after field measurements and data recording by dataloggers, the common atrium forms (spherical, prismatic, parabolic and flat at 3 m, 5 m, 7 m and 10 m) were replaced and in order to measure the heat stratification, the Mathematical formulas was used.

According to field observations and data measurements, the fifth floor and attic of the indoor skylight due to the influence of sunlight and lack of air conditioning, are critical areas of heat stratification and are out of range of thermal comfort throughout the year. Therefore, the amount of energy consumption during the year to provide thermal comfort in these floors is high, which can be reduced by reducing the levels of light-absorbing interior walls and using materials with high thermal capacity.

The results show that the flat form with a height of 3 meters, due to the reduction of light levels in the interior wall and the temperature difference between the floors is the most appropriate form of atrium for reducing energy consumption and cooling load up to 7% and reducing heat stratification in commercial complex in cold and dry climate of Mashhad city.

Determination of pollutant emission factors by time is the most important initial data in air pollution modeling. EPA's AP 42 documents provide the most comprehensive emission factor system for all industries based on process type, fuel, and control types. Target of this study, wasto investigate concentrations, emission factors of SO2, NO2 and CO in Ilam gas refinery.

In this study, concentrations of SO2, NO2 and CO and other required parameters such as temperature, pressure, flow rate and diameter of the 6 main stacks were measured by direct field measurements by Testo 350 XL. By results of these measurements and measurements of previous years in the refinery, the mean average for the two normal scenarios and the worst condition, and then the emission values ​​were calculated. Data analysis was carried out with a confidence level of 95%.

The estimated secondry, hourly, daily, monthly, and annual emissions from Ilam gas refinery was calculated and analyzed based on 2 normal and worst-case scenarios. Field measurement of flue concentrations showed that the highest concentrations of carbon monoxide (3565 ppm) and sulfur dioxide (5099 ppm) relates to SRU1 unit, the highest produced nitrogen dioxide (188 ppm) produced by SRU2, 1396 were the most polluted year according to the measured gases. The results of environmental measurements showed that CO at the sewage station is, 4/12 ppm and in Mehran road with an undetectable amount, the lowest amount of NO2 in the Chegae with 0.6 and Mehran road with the undetectable, the lowest amount, the amount of SO2 at the laboratory point with a maximum of 0.13 ppm and in the housing camp with an undetectable amount, the lowest It was.

Considering that the amount of environmental pollution and concentration of pollutants in the production units are more significant. So, planning for corrective actions to reduce emission of pollutants in production units, seems to be necessary. As well as the recovery and reduction of feed of flaring, can have a significant impact on the emission of pollutants.

Todays, due to the expansion of cities, large quantities of industrial and hazardous materials are produced, which, in order to prevent its long-term and dangerous effects on human and environmental communities, selecting the best site for these wastes has become one of the complex decisions in urban management action. Because of numerous industrial units, especially refineries, in Bushehr province, it is essential to find a management solution for hazardous wastes of this province. Finding the optimal location using multi-criteria decision models based on GIS that has both the lowest environmental risks and economically optimal, is the main goal of this article.

In this study, 24 parameters were used to analyze the selection of hazardous waste disposal sites based on the Delphi method in Bushehr province. Selected criteria were divided into two ecological and economic categories and ANP method was used to weight the criteria. At the final stage, suitable sites for these wastes were determined based on the GIS-based WLC method. 

The results showed that ecological criteria had the highest score (61/34%) and land use had the highest weight (0/27) and evaporation of the lowest weight (0/0017). Also, 6/13% of the province has a very high potential and 17/7% of the surface area is completely inappropriate for the disposal of hazardous wastes.

Study results highlighted the importance and significant weight of environmental criteria in prioritizing the proposed areas for hazardous disposal in Bushehr province, and has shown the model's efficiency in integrating GIS and MCDM.

This research, have considered the effect of environment education on the knowledge level, attitude and behavior of local society to protect the biological variety.

Research method is experimental partly as a pre-test and post-test by the control group. Statistical society in the research is 10628 families who are living in the place of Dena. Participants were selected by the way of voluntarily sampling and divided in to 2 groups of 30 persons randomly in testing group and control group. The people settle in to testing and control groups. This research used the researcher’s answer sheet that 15 specialized confirmed its apparent and concept and total stability of 30 questions equals to 0/9. Answer sheets were distributed among participants before and after the education and necessary description was explained about this research to them. Then, people in group of control and testing answer the questions. SPSS-21 software used to analysis the data.

Results demonstrated that Environmental education on the level of awareness of local communities has an effect equal to %72 which this amount was meaningful for error level less than 0.01.The results of the second hypothesis showed that Environmental education of local communities has the effect equal to %26 on the variable of attitude, that this was meaningful at the error level less than 0.01.The results of the third hypothesis showed that effectiveness of Environmental education of local communities in Biodiversity protection (Aspect of behavior), is %32  percent.

Investigation of general hypothesis of research demonstrate that Environmental education has meaningful effect on the level of awareness, attitude and behavior of local communities in Biodiversity protection.

One of the key issues in quantitative analysis of digital satellite data is to ensure that the sensitivity of the satellite's radiometer is stable after launch. Achieving such a goal requires radiometric calibration of the satellite sensor. The aim of this study was to investigate the possibility of using arid salt marshes as reference terrestrial phenomena for radiometric calibration of LISSIII and ASTER sensors. For this purpose, salt fields in dry areas of Damghan, Kashan and Maharloo were used for radiometric calibration of reflective bands of LISSIII and ASTER sensors.

First, the characteristics of salt fields in the study areas were evaluated based on previous research, field studies and available satellite data. Then, using the calibration relationships, the information in the guide files as well as the calibration coefficients of the sensors used, the spectral reflectance of the saltworks in the reflection bands were calculated and the correlation between the brightness of the images and the spectral reflection of the saltworks (satellite sensor radiation above the atmosphere) was evaluated.

The linear relationship and high correlation coefficient (more than 0.8) in each of the visible and infrared bands near LISSIII and ASTER sensors showed that arid salt marshes as reference terrestrial phenomena can be limited to radiometric calibration of LISSIII and ASTER sensors in LISSIII and ASTER sensors. And infrared close to have efficiency.

The results showed that the trend of changes is very consistent with each other (explanation coefficient between 0.8 to 0.9), in other words, with increasing the degree of brightness, the amount of spectral reflection also increases. Due to the linear relationship and high correlation coefficient (more than 0.8) in each of the visible and infrared bands near LISSIII and ASTER sensors, the atmosphere did not have much effect on the received radiation of the sensor.

Declining water resources caused usage of recycled water that sometimes not purified well.  The growing population and consequently increasing water demand, along with a shortage of available freshwater resources have inevitably led to the use of unconventional water resources. Irrigation lands with urban wastewater requires quality and quantity control for achieving food security. Therefore, the present study was conducted to investigate the effects of irrigation with urban wastewater on the concentration of Nickel and Cadmium in soils and their effects on plant, root, shoot, and functional characteristics of wheat.

  Field sampling was carried out at random from a depth of 0 to 20 cm. Wheat samples were taken at harvest from a 1-meter by 1-meter area. A total of 20 samples for Cadmium metal and 20 samples of Nickel metal were taken.

The results showed that the average concentration of Cadmium and Nickel was 10.6 and 49.43 kg, respectively, which resulted in an accumulation in various parts of the wheat plant. Increasing the concentration of Cadmium and Nickel in the soil increases the accumulation in the root, upper parts, and wheat seeds. Also, increasing the concentration of Cadmium and Nickel in the soil decreases the dry weight of the root, the shoot, and the weight of the thousand seed. However, there was no significant effect on two traits, number of grains per spike and number of spikes per square meter. The effect of Cadmium concentration was higher than that of Nickel.

Increasing 1 mg of soil Cadmium caused increasing, 0.81, 0.56, 0.6 mg Cadmium in root, upper parts and seed. For Nickel increasing the soil concentrations caused 0.29, 0.29, 0.11 mg in root, upper parts and seed.

Dynamics of Forest communities, before the climax stage, are very high, and small changes in the conditions of the stands would result in sudden responses such as dominant species changing or increasing the number of accessory species in the accessory stand. This study aims to predict the sequence of the beech- hornbeam stand toward beech stand in the semi-virgin forest Hyrcanian of northern Iran.

After field studies, three sample plots with an area of ​​one hectare (100 × 100 m) were selected, which included hornbeam-beech type (middle stage type of Hyrcanian forest sequence). At first, four species turbulence factors, the ratio of number of seedlings to mother rootstocks, the percentage of abundance of dry matter and the indices of diameter and height differentiation in the sample plots were measured.

Layering Charts of species indicate the conspicuous presence of beech in the understory of three stands with 61.3 percentage on average. In addition, the average number of proportion of seedlings to the number of mother trees in beech and hornbeam were are 30.1 and 2.3, respectively. The highest percentage of dead trees’ (67%) frequency in the plots is related to Hornbeam species. The results of the TDi and THi indexes charts, with averages of 0.13 and 0.1, respectively, demonstrate a dramatic competition between beech and hornbeam.

Through the measuring of the competition in natural stands and combining results with other factors such as stage and seedling frequency and layering in the stand indicate that beech would be likely to be replaced by hornbeem.

The value of non-market for environmental goods such as habitat protection and perspectives are important. The aim of this study was to evaluate the protective Khaeiz protected area is by use of contingent valuation method.

In this study the effect of different explanatory variables on respondents' willingness to pay for the Protection of logit regression model was used. The required data from 196 completed questionnaires were collected.  

 71% of respondents expressed a willingness to contribute to the protection of the region. Results of logit model estimation showed that the index trend of environmental variables, accountability, financial, environmental and offered membership in the organization are significant. The results showed that the expected value of the willingness to pay was 23948/5 million Rials. The monthly value of protecting the region against 18861/28 million rials respectively. The protective value against was determined 287382/7million rials annually in the study area. Dividing this figure by the total area of ​​ecosystems studied, the average per hectare of ecosystem protection against 8888 thousand (according to the area of ​​32332 hectares’ area) is obtained. It is recommended at least annually, equivalent to 8888 million (annual preservation value per hectare) Rials for investment protection Khaeiz area. It represents the estimated total value of ecosystem protection in the region. In other words, the ecosystem of the region also has many other values ​​for example, biological control of pests, pollination, water and soil conservation, medicinal plants and byproducts, capture and storage of carbon dioxide and produce oxygen, biological diversity , prevent soil erosion, combat air pollution, noise reduction, mitigation and climate stylized, green spaces and landscape and natural scenery, temperature adjustment, increase groundwater resources and consequently the springs and rivers, others noted that their value should be estimated.  

In this study, the current situation is an important step to safeguard protected areas and natural resources and move towards sustainable development. Also for planners, managers and decision-makers provide justification to the quantity and quality of natural resources to support them.

 Mangrove forests play an important role in carbon stock, but the amount of carbon stocks in mangrove ecosystems and also different mangrove species are different. Unfortunately, these ecosystems are at dangerous and valuable area of them have been destroyed recently. Furthermore, no attempt was done to estimate mangrove soil carbon stock in our country. Then, the objective of this study was to estimate A. marina soil carbon stock and compare it with the other mangrove forest in the world and also with other forest ecosystems of the country.

30 soil samples were taken from the depth of 0-20 and 20-50 cm, in summer 2015. Then the carbon stock of each horizon was determined. Furthermore, correlation between soil carbon stock and soil physiochemical properties were determined.  

In the present study, the average carbon stocks in 0-20 and 20-50 cm depth were 13.6 and 26.2 tons per hectare respectively. This means the carbon stock in A. marina soil values is 8756 dollars per hectare. Pearson correlation results revealed that soil carbon stock was significantly correlated with total soil nitrogen and electrical conductivity. While, there were no significant correlations between carbon stocks with the rest of studied parameters.

Finally, we can’t ignore the A. marina had high potential in soil carbon reservation and it can be affected by soil nitrogen and electrical conductivity. Higher soil carbon stock in subsoil compared to the topsoil can be related to the higher soil nitrogen of the subsoil.

The Department of Environment is the main custodian of environmental protection and the implementation of Principle 50 of the Constitution. The accuracy of the organization's performance shows the failure of the full and effective implementation of the assigned tasks, which has provided the ground for raising the issue of forming the Ministry of Environment. Proponents of this plan express Reasons like Creating integration and managerial cohesion, structural weaknesses and shortcomings of the legal system and lawful parliamentary oversight and opponents point to the confusion of sovereignty and entrepreneurship, the weakening of the main task of the institutions subject to merging and their different positions, and the difficulty of managing a multi-sectoral institution difficulty of managing a multi-sectoral institution. The present study, with its descriptive-analytical method, seeks to examine the possibility of forming the Ministry of Environment in the Iranian legal system. Studies have shown that fundamental legal problems such as the lack of a comprehensive sustainable development plan and environmental protection developed based on the general policies of the environmental system, as well as the existence of parallel, scattered and old rules and regulations lack comprehensive and systematic approaches to environmental management, affects the management of the department or ministry, and they must be addressed first. However, given the ministry's organizational, social, and legal status in the country's political system, the Ministry of Environment's structure seems to be more successful in creating and implementing these fundamental changes and solving existing problems.

Tissues that have been formed in the past and throughout a long process have been gradually weakened with the growth urbanization and urban development. On the other hand, the impacts of the immense growth of urban populations have led to a dispersed growth and the emergence of the marginalization phenomenon, having resulted in its own distinct problems. Yet, it is well-agree that the urban areas are the best option for urban development due to their existing infrastructure and urban amenities. Accordingly, the present paper seeks to locate these lands in the eroded urban fabrics of the Avini neighborhood by compiling the criteria and indices from theoretical texts and practical experiences to identify the lands susceptible to internal development.

In this regard, in order to reach a conceptual understanding and expert knowledge concerning the features of the lands susceptible to internal development, a questionnaire based on the theoretical framework was developed and completed by the urban planning experts on the one hand, the research method in this paper is, an F'ANP analytical method which is a combination of the functional analytical methods and the ANP; on the other hand, it is a secondary analysis of the location of the land susceptible to the development of an endogenous GIS.

The findings of this study acknowledged that among all the factors affecting the identification of the lands susceptible to internal development in the Shahid Avini neighborhood, the performance criteria, and the accessibility and the related indicators attained the highest priority and prominence in locating these lands. Furthermore, a number of the parts related to the brownfields and the workshop located in the north and northeast areas of the neighborhood had a higher priority compared to the other parts to carry out the process of endogenous development with a weight between six and nine.

In line with the results of this study, among all the factors affecting the identification of the lands susceptible to internal development in Shahid Avini neighborhood, performance criteria and access and related indicators have the highest priority and importance in locating these lands. In addition, parts with barren use and production-workshop located in the northern and northeastern parts of the neighborhood, with a spatial weight between six to nine, have a higher priority than other parts to perform the process of internal development.

  The aim of this study was to prepare the map of land suitability for passage in SaadAbad–Naharkhoran forestry plan, Golestan province and design the different variants of forest roads and choose the best one according to the amount of passage from land classes, openness percentage and surface distribution and modified tone-kilometer.

 The map of land suitability for passage was produced. Then, two variants were designed on this map using PEGGER and the amount of passage from land classes was estimated. Openness percentage and dead zones was determined by the calculating road density and skidding line and creating buffer. In Surface distribution algorithm, the distance from geometrical center of compartments to roads was measured. Tone-kilometer of variants was calculated according to skidding correction factor and conversion coefficient of volume to weight. The best variant was chosen based on AHP.

Results showed that existing road has passed from more suitability land as compared to other variants. Mean distance from geometric centers of compartment to first, second and existing variants were respectively 476.9, 480.3 and 428.8 m which indicates that existing road has better distribution. Maximum was recorded for first variant with amount of 82.3%. In tone-kilometer algorithm, each kilometer of existing road should bear 149.96 tones for extraction of woods from compartment. Existing road was better than two variants in terms of passage from suitability land, dead zone, surface distribution and ton-kilometer; so that after calculating the final weight it was determined that existing road is the best.

Besides considering all the criteria in evaluation of forest road network leads to more accurate understanding of the performance of each variant and choice the best one.

Over the past decades, climate changes and the limitation of surface water resources have caused excessive utilization of groundwater stocks, so that aquifers in most of the country's plains have no favorable situation now. Kaboodarahang plain is as one of the critical forbidden plains of the country which is facing water crisis. The status entails employing proper management of groundwater resources policies. The present study focuses on the economic, social, and environmental impacts of applying tax and subsidy policies per cubic meter of consumed or saved surplus water as an alternative to pricing approach.

This study was conducted and investigated via using Positive Mathematical Programming and Maximum Entropy Planning. Tax and subsidy policies were applied per cubic meter of surplus used or saved surplus water in three varying scenarios e.g. 329, 658 and 987 Rials. Needed data and information were obtained by referring to relevant organizations and 141 questionnaires completed via multi-stages cluster sampling method amid farmers of Kaboodarahng Plain during 2016-2017.

The results showed no significant change in the area under cultivation by applying tax and subsidy policies per cubic meter of surplus water consumed or saved, while rather drives the cropping pattern towards certain crops e.g. barley, cucumber and watermelon. Also, the outcomes of the research proved that applying the foregoing policies, besides reducing water consumption would increase the gross profit of target farmers.

Applying tax and subsidy policies per cubic meter of used or saved surplus water could not only motivate farmers to reduce their water consumption but provide a good alternative to water pricing policy.

Rapid urbanization and constructions are considered as the main cause of many environmental problems on the earth, especially in urban areas. Todays, functional and structural roles of green spaces have been emphasized further in improvement of urban ecosystem. As green space is one of the most important classes of land use in urban ecosystem, studying its changes is an important step in order to improve human-dominant ecosystems.

In this study, remote sensing and geographical information system were used in order to investigate spatio-temporal changes of urban green space in Ardabil city. To achieve the mentioned purpose, Landsat satellite images including TM-1987, ETM+-2000 and OLI- 2014 were used.

Results indicate that green spaces in Ardabil city have intensely decreased during the investigated time and in the during past 27 years about 1507 hectares of the green spaces of this region have been constructed and only 8 per cent of the city is covered by green space.

Results show intensive changes in spatio-temporal green space pattern in Ardabil city. In order to prevent further destruction and elimination of urban green spaces, along with improving it in Ardabil City, the existent policies should be revised.

Increasing population and construction of tall buildings have multiplied the presence of environmental pollutants in cities. On the other hand, people use open urban environments more than before to meet their living needs. In this regard, various factors such as the layout of buildings and the presence of continuous wind currents can play a significant role in the distribution of pollutant particles. The present study was conducted to determine the effect of the layout of high-rise residential buildings on the distribution of pollutant particles by recognizing the air flow in Tehran.

In this research, using descriptive-analytical and comparative methods, using simulation technique using ENVI-met software, wind behavior around the distribution of pollutants has been investigated and analyzed. The method of data collection has been done through library studies and field survey.

According to the modeling of the two different types of layout of selected urban block (Sobhan residential complex in Gheytariyeh district, Tehran)with similar building form–one as the existing situation and the other as the proposed model with orderly layout, the findings demonstrate that the layout alternation of residential blocks affects the natural airflow and wind speed between blocks and an improper and non-methodical locating of high-rise buildings causes a change in natural wind pattern and consequently, leads to secondary effects resulted from intensification or stagnation of wind and thus, influences the dispersion of pollutant particles.

In this research, the obtained results from the two models of buildings layout in the software and the output related to the intensity of wind and the retention level of CO show that the existing situation model is more desirable compared to the proposed layout due to more unified and higher wind speed throughout the site and also proper air circulation between blocks which causes the dispersion of pollution and prevents the retention of pollutant particles.

land use change, mainly socio-economic benefits to follow. However, these changes have negative effects on the natural environment. Due to the high volume of runoff from a lack of permeability in the city and Non-use of certain areas or any structure in addition to the problem of flooding in low-lying areas for water infiltration in several studies to develop models with simulation approach to land use changes have taken place. In this study, L-THIA model for estimating runoff from land use changes in the area of Khorramabad is used. The Model of L-THIA, a model to assess long-term effects land use change on water resources using simple and availability data Such as long-term climate data, land use map and soil map applicable.  

This study was conducted in a period of 10 years and in the period of 2004-2014. Landsat images from the site the US Geological Survey has been downloaded and various corrections have been made. Land use maps were prepared and used using Landsat 7 satellite images of ETM sensors and Landsat 8 images of OLI sensors related to 2004 and 2014, respectively. Precipitation data are provided by the Regional Water Authority. After sorting, they are prepared for future analysis. By combining land use map and soil texture map in GIS software, the soil hydrological group is produced. Finally, the prepared maps are given to the L-THIA model and the effect of land use change on surface runoff is investigated.

The results of modeling using L-THIA, increased annual runoff in ten years shows that this increased volume of runoff and the need for control over land use change in the region. User modifications to increase mainly in residential areas and loss of woodland and grassland.

As the results of this study show, the L-THIA model has a good ability to express the effect of land use change on the volume and depth of runoff. Also, using the results of the study, it is possible to prepare control programs for land use changes to prevent runoff in the area.