Geographic Information System (GIS)
Abolfazl Ghanbari; Vahid Isazadeh
Abstract
Extended AbstractIntroductionAir pollution is a major problemin large industrial cities and affects the life of urban citizens.Due to population growth,significant increase in the number of motor vehicles as well as the concentration and accumulation of industries, Tehran is in the grip of an air pollution ...
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Extended AbstractIntroductionAir pollution is a major problemin large industrial cities and affects the life of urban citizens.Due to population growth,significant increase in the number of motor vehicles as well as the concentration and accumulation of industries, Tehran is in the grip of an air pollution crisis. Previous studies have indicated that once every three days, Tehran faces increased levels of pollutants and air pollution.Ozone is produced through photochemical reactions between hydrocarbons in carexhaust and nitrogen oxides in the atmosphere. Producedthrough reactions between atmospheric pollutants,this pollutant is not primarily released into the environment by a specific sourceand thus, it is called a secondary pollutant.Concentration of ground-level ozone has doubled over the last century.Exposure to this pollutant is very harmful for human health, especially those who exercise outdoors because it severely damages their lungs.Therefore, increased concentration of pollutants has become a major challenge for the management of metropolises such as Tehran. Having information about the spatial distribution of pollutants allows urban managers to take appropriate measures and reduce pollution related risksfor areas and people in danger.Due to excessive concentration of industries and factories inside the geographical boundaries of Tehran, along with its specific geographical condition, topography and climate, Tehran has become one of the seven most polluted cities of the world.The present study seeks to model the spatial and temporal changes of ozone and nitrogen oxidesin Tehran metropolis. Methods and MaterialsIn this cross-sectional descriptive study, spatial analysis of pollutants (ozone(O3) and nitrogen oxides)is performed based on data measured by Tehran air quality monitoring stations for the 2008, 2009, and 2018reference periods. For 2008 reference period, data were collected on a monthly basisfrom the website ofTehranair quality control company,while for 2008 and 2018, data were collected annually. Arc GIS 10.5 released by ESRI was usedfor spatial analysis, and Microsoft Excel 2013 was usedto drawdiagrams and perform other analysis.Inverse distance weighting (IDW) model was used for spatial analysis of ozone and nitrogen oxidesin Tehran metropolitan area inthe three reference periods. Finally, the reference periods were compared and the most polluted one was zoned using the IDW model. In the second method, Google Earth Engine was used to model the spatial distribution of ozone and nitrogen oxides. In this method, Sentinel-5p NRTI O3: Near Real Time Ozone product was used to model ozone and nitrogen oxideson an annual basis (11/01/2018 and 28/03/2020).This is the date in which sentinel has started monitoring ozone and nitrogen pollutants. As the most important product available for measuring the average rate of change,column of ozone and nitrogen oxides’ changes in the atmosphere (O3_Column_number_density) was used in this study. Annual average concentration of ozone and nitrogen pollutants in Tehran was compared with the Sentinel-5 product in Google Earth Engine. Results & DiscussionIn 2018, average annual concentration of ozone and nitrogen oxides in studied stations equaled 12.7 ppb. The accuracy of modeling was also calculated using the coefficient of determination(R2) or coefficient of detection (CD). The average annual concentration of ozone and nitrogen oxides in 2008 was also measured for all air quality control stations to determine their correlation.All independent variables used in this model had an acceptable level of significance (P.> 0.001).In other words, all parameters improved the performance of the model in estimating the concentration of ozone and nitrogen oxidespollutants. The model was developed and R2 rate for 2008 monthly average equaled 0.9188%.The coefficient of determination (R2)for ozone and nitrogen oxides’ concentration in 2009 equaled 0.9134%, but the annual average of 2018showed a much lower R2which equaled 0.476%.It should be noted that not all stations have been evaluated in this study, because the concentrations of ozone and nitrogen oxidesin some air quality monitoring stations equaled zero. Thus, only stations showing a greater than zero value have been used in this study. ConclusionAs previously mentioned, various models have been proposed for modeling the concentration of ozone and nitrogen oxides, each showing a different result. In the present study, the inverse distance weighting (IDW) model was used for three reference periods (2008, 2009 and 2018), and the concentrations of ozone and nitrogen oxides in the atmosphere were also modeled using the variables related to air quality monitoring stations.Ozone concentration modeled by inverse distance weighting method was compared with the average annual change of ozone concentration derived from Sentinel-5 product in Google Earth Engine. Results obtained from the concentration of ozone and nitrogen oxides in the three reference periods were investigated using thecoefficient of detection.The resulting coefficient of determination for ozone concentration in 2008 and 2009 equaled 0.9188% and 0.9134%, respectively. The lowest coefficient ofdetermination for ozone and nitrogen oxidesconcentration was obtained for 2018 which equaled 0.476%. Regarding the spatial distribution of ozone and nitrogen oxides in 2008, the highest concentrations were observed inMasoudiyeh, Punak, Rose Park and Aqdasiyeh stations, and the highest concentration of nitrogen oxides was observed in District4, Crisis Management Headquarterand Sadr Expressway(District 3). In 2009,the station in Rose Park (District 22) showed the highest concentration of ozone and nitrogen oxides.In 2018, IDW modelling and spatial distribution of ozone and nitrogen oxidesshowed a different result. In this reference period, the station in district 4 received the highest annual concentration of ozone and nitrogen oxides, and north eastern areas ofTehran was regarded as the most polluted areas based on the concentration of these pollutants. But stations in16th, 19th and 20th districts and Masoudieh station (15th district) had the lowest annual concentration of ozone and nitrogen oxides. In general, it can be said that spatial modeling with Sentinel-5 product has been able to model the concentration of ozone and nitrogen oxides inall stationsof Tehran on a pixel by pixel basis.
mohammad kazem shams pouya; Jamileh Tavakolinia; Mozaffar Sarrafi; Zohreh Fanni
Abstract
Extended Abstract The concepts of land and land use planning and its objectives have changed over time. These changes include: Changes in the socioeconomic concept, the evolution of the concept of land, physical and new priorities in land use per capita. In addition, seeking to promote the environmental ...
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Extended Abstract The concepts of land and land use planning and its objectives have changed over time. These changes include: Changes in the socioeconomic concept, the evolution of the concept of land, physical and new priorities in land use per capita. In addition, seeking to promote the environmental movement in the 1980s led to the global popularity of the concept of sustainable development, qualitative changes in approaches and methods of planning and urban design. Since then, urbanization goals have changed from physical and functional issues towards the sustainable urban development. In fact, equitable access to land is one of the components of sustainable development. The true role of land and its importance in sustainable development is properly understood when its prerequisites are taken into consideration. One of the most important of these prerequisites can be pointed to good land governance. Alongside this revival of land issues in development policy discourse, is the emergence of a distinct pole in governance discourse, namely, ‘land governance’. The term and notion of ‘land governance’ has gained currency within the mainstream agencies in recent years, and generally means the most efficient way of administration of land issues, such as cadastres, land titling, and so on. Land governance encompasses a range of issues and subjects that the laws and policies of urban land is one of those cases. So, the urban land laws and policies from the perspective of good governance approach Provides good understanding of the policies and rules and patterns of urban land issues. Materials & Methods The main method of this study was a descriptive-analytical approach that has been carried out using a literature review in library data. This research is both fundamental and practical. The main goal of this study is to determine the characteristics and consequences of good and poor governance and the interpretation of laws and policies from the perspective of good land governance model and determining the obstacles to fulfill the requirements of good land governance in Tehran Metropolis. Results & Discussion In the Third Development Plan (1962-1967), the master plan for Tehran Metropolis was prepared. Such plans led to long-term government intervention in the land market. It should be noted that the criterion of 300 meters for land separation in the first comprehensive plan of Tehran was far beyond the average residential land area in the status quo (about 100 meters) and was beyond the capacity of low-income groups.This pattern was repeated in subsequent programs and led to projections of lower income groups to the suburban areas. Whereas good land governance requires knowledge and beyond citizen participation and interest groups in the preparation and implementation of development programs and urban land policies, effectiveness and efficiency is one of the most important criteria for good land governance that must be based on accurate and perfect laws and regulations. In Tehran Metropolis, the lack of adequate and affordable housing, especially for low-income groups led to poor governance of land and housing. Also, given that decision-making process is centralized, the local land management has not been achieved. Conclusion The results showed that, zoning laws, land separation regulations, and housing planning flaws led to speculation of land and housing in Tehran metropolis and ignored low-income groups in urban plans and increased urban sprawl and expansion of the unregulated constructions as a result of poor land governance. Also, it is necessary to mention that the land acquisition and construction by various institutions without permission, the institutional irregularities, centralized decision-making process and the lack of formation of local land management, lack of transparency and unclear land property situation within and outside the cities, all of which are in contradiction with the principles of good land governance. Good land governance is based on transparency of ownership, land tenure security and transparency and so on. This is a very basic issue that also continues. Therefore, the need to revise the governance structure along with subsidiarity and providing the context of popular participation, and institutions such as councils by state are the essential issues. In the end, it must be emphasized that the realization of local land management also depends on good land governance.
Hossein Hatami nejad; Ashraf Azimzadeh Irany
Abstract
Given that cities have the majority of the country's population and are often the economic, political, cultural, social and governance centers in countries, theirreadiness against crises (passive defense) should always be considered by the relevant experts. Organizing the city on the scale of the neighborhood ...
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Given that cities have the majority of the country's population and are often the economic, political, cultural, social and governance centers in countries, theirreadiness against crises (passive defense) should always be considered by the relevant experts. Organizing the city on the scale of the neighborhood (as the smallest and most effective urban unit) based on the requirements of passive defense, in order to deal with the crises (natural and man-made) and minimizing the hazards using geographical techniques and urban planning, are the objectives of this research. Therefore, the sixth district’s neighborhoods of Tehran’s 2nd region were selected as a case study and the results of the research were presented so that the possibility of generalization of similar surveys and studies in other urban areas would be provided. The present research is an applied- type, and the method of the research is normative-analytical. The scientific foundations of this research are based on the concepts of urban crisis management with an emphasis on geography and urban planning knowledge. In this research, after the recognition and evaluation of the present situation, the dimensions of the vulnerability of neighborhoods at the time of the crisis, the strengths and weaknesses, as well as the threats and opportunities of each neighborhood have been investigated with the passive defense approach, and the relevant conclusions have been drawn on this basis. Data collection was done based on library method and field studies, and a comparative method was used to provide the conclusions. In this research, the SWOT analytical technique was used to determine the strengths and weaknesses, threats and opportunities, as well as to provide strategies, policies and suggestions for necessary actions, and ArcGis software was used to display and analyze the descriptive data. The results of the research indicate that the attention to components such as city structure, urban texture, city form, urban land use, and finally the social contributions of residents of each neighborhood, can make it possible to organize urban neighborhoods based on the requirements of passive defense. The results of the research reflect the fact that paying attention to the components such as city structure, city texture, city form, urban land use, and finally the social contributions of the residents of each neighborhood, can make it possible to organize urban neighborhoods based on the requirements of passive defense.
Amir Hossein Kazem; Farhad Hosseinali; Ali Asghar Ale-sheikh
Abstract
Modeling urban growth and land use changes are an integral part of planning for sustainable development. The present research intends to model the urban growth and development for Tehran metropolis from the aspect of timeand spatial distribution. To this end, land-use maps for the years 1988, 2002 and ...
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Modeling urban growth and land use changes are an integral part of planning for sustainable development. The present research intends to model the urban growth and development for Tehran metropolis from the aspect of timeand spatial distribution. To this end, land-use maps for the years 1988, 2002 and 2013 were categorized with the object-based approach using Landsat satellite time series images. In the next step, using the logistic regression model, the effect of independent variables in relation to urban growth including 14 variables in the form of two groups of environmental-natural and socio-economic variables during the period of 1988 to 2002 was calculated as the coefficient in the regression equation, and the potential map of urban expansion was produced. The evaluation of the logistic regression function using two Pseudo R2 and ROC indexes with values of 0.32 and 0.89 showed good regression fit and proper description capability. Subsequently, the area of change for the expected year was quantitatively predicted using Markov chain analysis.Finally, by using the outputs of the two models of logistic regression and Markov chain analysis and using the Cellular Automata Model, urban growth was modeled for the year 2013, comparison of which with the 2013 classified image, shows that the used model with a 93% relative accuracy for the estimated area and a Kappa coefficient of 0.87 has been a successful model. Accordingly, the same model was used to estimate the urban growth in 2025,using images from the years of 2002 and 2013.
Esmail Nasiri
Volume 22, Issue 88 , January 2014, , Pages 92-99
Abstract
Basically, solid waste management system is one of the most important items in controlling production, saving, consuming, and also in waste collecting and disposal. The main goal of urban solid waste management is to create an effective and sanitary collecting system which responds to citizens’ ...
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Basically, solid waste management system is one of the most important items in controlling production, saving, consuming, and also in waste collecting and disposal. The main goal of urban solid waste management is to create an effective and sanitary collecting system which responds to citizens’ needs. On the other hand and due to the importance of sustainable development in urban societies, solid waste management is now one of the latest sciences which can decrease the influences and damages caused by consumerism to a considerable degree. Abundance of solid waste is the inevitable result of development and consumption, while lack of management is one of the most important factors in creating environmental pollutions. In addition to the costs of burying wastes, costs of collecting waste have also increased and most of waste management costs are related to collecting urban solid wastes. There are different plans for collecting urban waste, based on the type, composition and amount of produced waste, social and cultural features and urban priorities. According to the World commission of Environment and Development, sustainable development satisfies the present generation’s needs, without damaging the future generation’s capability in satisfying their needs. Not only physical resources, but also human resources must be maintained in development. Sustainable development begins with people and their cooperation; which are crucial in maintaining sustainability in economic, social, ecological and political stages of development.
Ali Mohammadpour; Kheder Faraji Rad
Volume 22, Issue 85 , May 2013, , Pages 5-26
Abstract
Tehran as a political and economic capital city of Iran has an unsafe structure and the safety issue have not been considered until now. However, Tehran is faced several natural disasters, including earthquikes and it is essential to identifying and addressing the specific framework of urban spatial ...
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Tehran as a political and economic capital city of Iran has an unsafe structure and the safety issue have not been considered until now. However, Tehran is faced several natural disasters, including earthquikes and it is essential to identifying and addressing the specific framework of urban spatial divisions for the efficient management during crisis in Tehran. This article try to answer therefore, aims to answer this fundamental question that what the appropriate zoning of the Tehran city is, with emphasis on crisis management.
The GIS and AHP combined and qualitative method were used to answer the above question. The results demonstrated that many parts of Tehran are in the areas with high vulnerability (16446.75) hectares.
The results, also showed that (10004.25) hectares of Tehran are among the areas With medium vulnerability. In addition the above results, the article conclude that the administrative divisions of Tehran is not corresponded With the determined activites and tasks of the professional committees of organization of prevention and crisis management of Tehran city, therefore, is necessary to redefine the administrative divisions of Tehran in relation to crisis management.
Mahdi Modiri; Zahra Alibakhshi; Faramarz Khoshakhlaq; Ali Hanafi
Volume 21, Issue 84 , February 2013, , Pages 7-20
Abstract
In order to recognize the effective synoptic system in creation of moderate and severe frosts in Tehran and the conditions under which sever and moderate storms transform into one another, synoptic analysis has been implemented by mean sea level 850 and 700 hp maps in a period of 45 years (1961-2005). ...
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In order to recognize the effective synoptic system in creation of moderate and severe frosts in Tehran and the conditions under which sever and moderate storms transform into one another, synoptic analysis has been implemented by mean sea level 850 and 700 hp maps in a period of 45 years (1961-2005). The synoptic results indicated that the transformation of moderate frost into severe and exterminator frost is because of cold weather advection from higher latitude, setting of through over region or earthly radiation. Surveying 850 hp maps, it was recognized that decreasing of temperature in research region arises from the cold advection of various systems from northwest to northeast. In mean sea level maps, extension of Siberian high pressure ridge, and in 700 hp level, setting of through over the eastern part of the district has the most frequency and share in moderate and severe frost formation.
