Adel Khazaei; Majid Abaspour; Sasan Babaei Kafaky; Lobat Taghavi; Yousef rashidi
Abstract
Introduction: The metropolis of Tehran as the largest capital of the Middle East is faced with phenomena such as environmental degradation, land use change and high concentration of agricultural and industrial disasters. Knowing the changes of land use in the past and predicting its future status is ...
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Introduction: The metropolis of Tehran as the largest capital of the Middle East is faced with phenomena such as environmental degradation, land use change and high concentration of agricultural and industrial disasters. Knowing the changes of land use in the past and predicting its future status is necessary in order to carry out a principled, dynamic planning. In this study, the spatio-temporal dynamics of land use changes in the Tehran in a 20-year period and the prediction of future changes in these land uses in the next 40-year were selected as the general objectives of this study.Material and Methods: After forming a database of Landsat 5 and 8 satellite images for three times of 2001, 2011 and 2021, the land use map of this times were prepared. For the validation of the maps Google Earth images, ground points and accuracy and Kappa coefficients were used. The time period from 2021 to 2061 was considered to predict future changes. In order to zoning and predict the future of land use changes, 6 land use change transfer sub-models with artificial neural network, Markov chain, and LCM model were used. Evaluation of the accuracy of the model was obtained from the comparison of the ground map of 2021, the future map of 2061, and the values of Null success, success, Miss and False Alarm were obtained.Results and Discussion: The results showed that the period from 2001 to 2021 was associated with the expansion of residential areas, the growth of urban areas and the reduction of green spaces including gardens and parks. The expansion of residential areas has been primarily in poor and barren soils and then in gardens and green spaces. This urban growth was clearly in region 5, 21, 22 and its physical development process was linear. The decrease in the level of gardens and green space is very catastrophic and this decrease is especially evident in the central areas of the city due to the high density of buildings. Urban parks are clearly in a complicated condition in the eastern areas of Tehran. The area of rain fed agriculture has increased and the area of barren soils and poor lands has decreased. Most of the changes in land use related to low capacity lands and agricultural lands have occurred. Studying the maps of the future of land cover showed the continuation of the same trend of the past 20 years. Although the growth of residential areas will be slower than the previous period, but the capacity and dimensions of the city will continue to increase, especially in the western, southern and southwestern regions. The decreasing trend of gardens, parks and urban green space is still observed. This process is more intense in the case of parks and they will be destroyed more quickly. The reason for this is besides drought and withering of trees due to climate change, pollution, and conversion of these green land uses to rain fed agriculture, parks, poor rangelands and urban areas. As for the urban green spaces, the 16 and 4 regions have the worst positions, and the 17, 19. 2, 5 and 22 regions will not be safe from this damage either. The decrease in the area of rangelands and cities moved to new areas will increase; the cycle of destruction of vegetation will increase from the outskirts of Tehran.Conclusion: Construction was more in the south of Tehran and the decreasing trend of urban green space will continue to be observed. The central areas of Tehran will be completely devoid of trees due to the predominance of the urban areas, and the point to consider is the destruction of the green belt in the north of Tehran in the future.
Zohreh Fanni; Mohammad Amin Hounakzahi; Manijeh Ghahroudi
Volume 16, Issue 1 , April 2018, , Pages 173-190
Abstract
Introduction: Environmental problems are one of the most important issues in major cities, metropolises and it is the result of confliction with the natural environment because urban development is necessarily associated with the domination of buildings, industries, transportation, and economical activities ...
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Introduction: Environmental problems are one of the most important issues in major cities, metropolises and it is the result of confliction with the natural environment because urban development is necessarily associated with the domination of buildings, industries, transportation, and economical activities on natural spaces. Strategic Environmental Assessment A comprehensive, formulated and systematic environmental impact assessment of policies, plans, and plans with their options include reporting through their findings and their application in the decision-making process.Materials and methods: A descriptive and analytical method was used to study and evaluate the strategic environmental impacts of urban development, Based on the concepts of the Strategic Environmental Assessment (SEA), using MADM statistical techniques and operational research, such as Analytic Hierarchy Process Analyzer (AHP),for proper emphasizing and valuation between experts (whose content was calculated using the Cochran formula) related to urban management and environment such as municipality, environment, governorate, natural resources, etc. were distributed and completed. Finally, the results were analyzed by Expert choice software.Results and discussion: The aim of the SEA process is to recognize the advantages and disadvantages of the environmental effects of a comprehensive plan and minimize the negative impacts of the implementation of the plan. For strategic evaluation, 2 criteria and 10 sub-criteria were selected which after assessing and evaluating the environmental criteria, sanitary exclusion of wastewater and residues were weighed 0.417 and reducing air pollution with a weight of 0.245 are the most important and in the top priorities, and sub-criteria of emphasis on improving the quantity and quality of water resources with a relative weight of 0.208, restoration of green space or missed pastures with relative weight of 0.077 and emphasis on the increased in soil quality and its fertility with a relative weight of.053 are in the third to fifth priority levels, respectively. Among the non-criteria related to the physical component, the realization of a healthy city plan, increased in access to open space and green, and payingattention to the urban architecture of the native with weights of 0.34, 0.264 and 0.159 are in the first, second and third, respectively. Quality improvement measurements for informal settlements with a relative weight of 0.094, realization of optimum density with relative weight of 0.085 and the optimal distribution of applications in the city with a relative weight of 0.058 are in the third to sixth priority.Conclusion: Zahedan has suburban neighborhoods such as Shir Abad, Karim Abad, Babaeyan, etc. Most of these neighborhoods are deprived of welfare infrastructure such as water, sanitation and... The structure and texture of soil geology are such that there is no possibility of constructing wells, According to the results of strategic assessment, urban environmental pollution such as sanitary wastewater-residues, pollution, air pollution, water pollution, restoration and access to open and green urban areas, access to a healthy and habitable city, attention to architecture - local urbanism and ... which all of them are the consequence of accelerated development of modern cities. Therefore, more attention of officials, planners and urban managers is required to prevent more urban environmental degradation, and it is necessary to provide citizens with fair access to welfare indicators.
