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An Analysis of the Reasons for the Decline of the Position of Tabriz Metropolis in the Urban System of Iran and the Prediction of its Population and Position by 2031 Texto completo
2021
Ghorbani, Rasoul | Alizadeh, Hooshmand | Karami, Sonya
Demographic changes in recent decades have led to rapid changes in Iran's urban system and its hierarchy, with one of its consequences being the increase or decrease in the ranking of cities in this system. The present study examines the position of Tabriz metropolis in the urban system of Iran from 1335 to 1395, and by forecasting the population of this metropolis by 2031, it tries to determine the future position of this city in the urban system of Iran. This study is practical in terms of purpose and descriptive-analytical in terms of nature and research method. The data in the present study were obtained through document analysis and field study (questionnaire and interview). Interviews were used to understand the causes of emigration and a questionnaire was used to understand the causes of fertility decline in Tabriz metropolis. The sample sizes for both instruments were determined based on the saturation principle. The exponential model, Spectrum software, and rank mobility index were used to predict the demographic factors, population forecast, and the study of metropolitan rank changes in the urban system, respectively. The obtained results showed that the decrease in fertility rate and migration are the main reasons for the sharp decline in population growth in the metropolis of Tabriz, with the economic reasons being the main reason. In addition, assuming the fertility rates of 1.5, 1.8, and 2.1 in Tabriz, we will see 1.64, 1.69, and 1.74 million increases in the population of the city, respectively, as well as a decrease in the population of minors and a doubling of elderly population over 65 by the year 2031. The results of population forecast show that the position of Tabriz metropolis will be stabilized as the sixth largest city of Iran's urban system by 2031, but its distance from the seventh metropolis (Qom) will be less, which requires special attention and proper management to prevent its rank from falling again.
Mostrar más [+] Menos [-]The Evaluation and Modeling of the Impacts of Urban Development on Landscape Patterns in Karaj Metropolis Texto completo
2021
Mohammadyari, Fatemeh | Mirsanjari, Mir Mehrdad | Zarandian, Ardavan
The goals of the present study were to analyze changes in land cover and to estimate a future scenario for 2028 using an artificial neural network in the Karaj Metropolis. To this end, the effects of land use changes in response to urban expansion on landscape patterns were investigated in three baseline, current, and future scenarios using landscape metrics and gradient analysis. The results showed that during a 22-year period, the agricultural and Garden lands have been severely damaged due to urban expansion. The results of the evaluation of changes in landscape also indicate that urban expansion in in development in the north-south transect to the margins (especially northward) and the east-west transect with a gentle slope to the west of the region. It is also anticipated that in the future scenario, if the current trend continues, the northern margin of Karaj metropolis will be changed from natural environment to a completely human-made one. Therefore, considering the results of the Pd and Ed metrics in both transects over the three examined years, it can be said that the area has expanded to the margin and there has not been much changes in the landscape of downtown. In addition, the decrease in the Pd and NP in all three scenarios indicates the consistency of urban landscape. In general, population growth and urban development have made the landscape pattern in Karaj metropolis to be a more regular and less varied one. The results indicate that spatial heterogeneity has altered the landscape patterns. Therefore, the growth of construction land in some areas should be restricted, and balanced development should be adopted to prevent the fragmentation of the landscape.
Mostrar más [+] Menos [-]The Evaluation of Geomorphologic Landforms for the Development of Human Settlements: A Case Study of Southeast Cities of Razavi Khorasan Province Texto completo
2021
Mohamadkhan, Shirin | Namjooyan, Reza | Barzkar, Mohsen | Abbasi, Mosa
The habitat development and establishment are directly related to the natural bedrock and geomorphologic complications. Due to topographical and geological conditions, the area under study has certain limitations in locating and developing human settlements. In order to reduce the hazards in the southeast of Khorasan Razavi province and modify plans for the development and establishment of human settlements, the feasibility of the area under study for residential development was investigated. After conducting library and field studies and selecting appropriate criteria, the fuzzy logic model was applied using the GIS software to identify areas for habitat development and establishment. In this study, to identify the potential areas for habitat development and establishment based on geomorphologic landforms, eleven parameters – including slope, slope direction, elevation, soil, land use, elevation, distance from fault, distance from river, distance from road, distance from settlement, and geomorphology – were used as independent variables in identifying geomorphological abilities and bottlenecks in the area. The results of zoning based on the fuzzy model showed that about 61% of the study area is located in very inappropriate and inappropriate classes, which means that geomorphological conditions in this part of the study area are unfavorable for the development and establishment of human settlements. About 14.58% of the study area has moderate conditions and about 24% of the study area shows favorable geomorphological conditions for construction activities and creation of new habitat areas. Alluvial fan units and alluvial plains are the most suitable sites for habitat development and establishment.
Mostrar más [+] Menos [-]Changes in Water Surface of Aquifers Using GRACE Satellite Data in the Google Earth Engine: A Study of the Urmia Lake Watershed From 2002 to 2017 Texto completo
2021
Issazadeh, Vahid | Argany, Meysam
Investigating the changes in groundwater aquifers in planning the sustainable management of water resources in each region is of particular importance. Therefore, reducing the level of groundwater aquifer changes requires proper management and planning to exploit water resources. In this study, the level of groundwater aquifer changes in Urmia Lake basin was examined for the period from 2002 to 2017 using GRACE satellite data (JPL, GFZ, CSR triple bands, CRI Filtered model, time and space filter, and Lew-Thiknth uncertainty dry product) in the Google Earth Engine. The results of the triple bands showed that the JPL band estimated the average level of groundwater aquifer changes on May 1, 2004 as 14.947 cm, while the GFZ band on estimated this as -30.558 cm on September 1, 2015 and the CSR band estimated this amount as -28.206 cm. Therefore, CRI Filtered model can very accurately identify the boundary between land and water zones. The results showed that this model estimated the maximum thickness of liquid water in the groundwater aquifer at March 31, 2002 as about 11.599 cm and its uncertainty at about 9.767 cm. It can be said that the least amount of thickness of liquid water is estimated on 13 August 2015 as 12.309 cm with an uncertainty level of 10.759 cm. According to the results, the level of groundwater change in aquifers in terms of liquid water thickness parameter (Lew-Thiknth) in the northern parts of the Urmia Lake basin and in terms of uncertainty in the northeastern part of the Urmia Lake basin is experiencing a strong decline in the aquifer water levels.
Mostrar más [+] Menos [-]Modeling the Process of Spatio-Temporal Changes in Land-Use and Urban Development of Ahvaz Based on Spatial Planning Approach Texto completo
2021
Abiyat, Mohammad | Abiyat, Mostefa | Abiyat, Morteza
The land-use changes and urban development are among the fundamental topics of spatial planning. Monitoring changes in previous years and predicting these changes in the coming years have a significant role in planning and organizing urban spaces. The purpose of this study was to investigate land-use change and urban development in Ahvaz with a landscaping approach based on balanced urban development. .Images of TM (1989), ETM+ (2002), and OLI (2019) of the Landsat satellite are the basis for analyzing this trend. LCM model was used to identify the past changes, while CA-Markov chain model was applied to predict the future changes. These images were classified using a support vector machine algorithm of the object-oriented method, and the land-use maps were prepared using three sensors with four classes of vegetation, barren areas, constructed areas, and water zones. The accuracy of maps was improved separately using NDVI and SAVI indexes in the classification of the images. The efficiency of the indexes was measure by kappa coefficients and the overall accuracy of land-use maps, and then changes were investigated using maps related to the superior index. The results showed that maps related to the SAVI index were more accurate and accordingly, they were used in assessing land-use changes. The LCM model showed that in the periods 1989-2002 and 2002-2019, 2602.92 hectares and 31174.77 hectares were added to the built areas, respectively. In both periods, the most changes were about converting barren lands to built-up areas and the least changes were related to the transformation of the built-up areas to water areas. The results of the CA-Markov model until 2029 showed the continuity of the increasing trend of built-up areas, such that in ten years, 2238.82 hectares will be added to the built-up areas, and it is anticipated that the area will reach approximately 12345.63 hectares by 2029.
Mostrar más [+] Menos [-]An Analysis of the Continuity and Cohesion of Urban Ecologic Network Through a Graph Theory Model Texto completo
2021
Gorbani, Rasol | Rostaei, Shahrivar | Karbasi, Pooran
Nowadays, problems related to the environment, society, and identity of cities derives from their expansion and the increasing penetration of natural space by human-made space. Green spaces are deemed not only as a green patch at the disposal of the masses, but also as a factor for the improvement of citizens’ life. On the other hand, the destruction and removal of homogeneity and continuity of natural infrastructures and green networks threatens the biological diversity and brings about limitations for development. Therefore, continuity of the urban green spaces provides habitats and corridors that help the preservation of biological diversity. To develop green space networks, increase continuity, and revive biological diversity, urban planners have used landscape ecology principles. Adopting a descriptive-analytical method and review of the scientific resources, this study investigated landscape connections and their importance for the preservation of biological diversity. Maragheh city green space network was modeled in GIS according to Graph theory. Then, the ecologic continuity analysis was carried out through Conefor software along with Integral Continuity (IIC) measure and point picking algorithm, and the urban green patches were valuated. At the end, the potential corridors in Maragheh city were identified using the least cost method, which then developed and improved the green space networks. The results of this study reveal that the majority of the built corridors are located around the city like a green belt. The main reason for this is the positioning of the main habitats in the city outskirts. Moreover, the green space network developed based on Graph theory made the complex landscape simpler and more organized, and helped with the identification of green space and the guidance of urban planning for the protection of biological diversity.
Mostrar más [+] Menos [-]The Provision of an Optimal Model for the Demarcation of the Protected Areas of Gas Transmission Operational Areas Using Spatial Allocation Method Texto completo
2021
Karimi, Touraj | Faraji, Amin
One of the main challenges in the energy transmission arena (especially the natural gas transmission) in Iran is the optimal demarcation of operational boundaries in order to cover the whole land. In other words, over time and due to the changes in the consumption level and the facilities installed in the related areas, the boundaries defined as the operational areas have lost their optimal response potential, and there have appeared challenges such as more difficult access, increased volume and importance of transmission, etc. Therefore, it is necessary to define and demarcate new boundaries based on these changes. As a result, this article addressed the optimal model for the demarcation of natural gas transmission operational areas using spatial allocation method. Spatial allocation method is an instrument for maximum optimization and high access in various algorithms. The spatial allocation methods that are usually used for positioning stations and work facilities are a great instrument for planning the public services. In this study, in line with using comparative studies and external experiences, instruments such as interview (for the determination of indices), statistical tests in GIS, weighing methods, etc., were used. According to the obtained results, the number of yards and areas should be fixed, but the boundaries of the operational natural gas transmission areas and yards should be mobilized maximally to match the defined scenario so that maximum optimization is achieved.
Mostrar más [+] Menos [-]An Analysis of the Effects of the Change in Climate and Surface Soil Conditions on the Frequency of Dust Storms: The Case Study of Khorasan Razavi Province Texto completo
2021
Naeimi, Maryam | Khosroshahi, Mohammad | Mir Akbari, Maryam | Gohardoost, Azadeh | Zandifar, Samira | Ensafi Moghadam, Tahereh
In recent decades, dust storms have intensified due to climate changes, including drought and human interventions. In addition to removing soil particles, dust brings storms bring about severe economic, social, and health problems. Due to its strategic conditions – including its status as an industrial and agricultural hub and the province hosting more than 29 million Iranian and international pilgrims, especially during the seasons and months with specific holidays – should be prioritized in the examination of dust storm frequency. The purpose of this study was to examine and track the frequency of dust storms and analyze the effect of climactic changes on them through the investigation of drought trend as well as the trend of changes in the land surface coverage percentage during the statistical analysis period. The results of counting the dust codes showed that dust storms with local origin had the highest frequency. According to the monthly analysis, Sarakhs and Mashhad stations had the most dust phenomena, with the most dusty days in the study area during summer and spring seasons, especially June and July months. The results of regression analysis of drought index and the monthly local dusty days indicated the existence of a significant, positive relationship between dust increase and drought intensity in Mashhad and Sarakhs stations during the statistical period of 27 years at 99 percent confidence interval. Finally, in the light of the results obtained from the examination of the land surface changes, it is recommended that land use plans be used along with short-term methods of soil stabilization in order to reduce the economic damages and preserve people’s health against dust during busy months and seasons so as to achieve the goals of long-term methods.
Mostrar más [+] Menos [-]The Identification and Analysis of the Strategic Variables Effective on the Future of Yazd Province Through a Structural Analysis Approach Texto completo
2021
Kalantari- Banadaki, Seyedeh Zahra | Abbasi-Shavazi, Mohammad Jalal | Abooee Ardakan, Mohammad
The intelligent managers of this era of constant changes and instability try to know opportunities, challenges, and variables effective on the system under their management so as to increase the possibility of their success. The managers of Yazd province – as one of the developed provinces of Iran – always try to step in the direction of sustainable growth and development by means of strategic planning, knowledge about the capacities of this province, and the management of the possible future challenges. The study at hand was carried out to attain this objective and to get a clearer image of the future of this province in order to identify the variables that are affective on the future of Yazd province. Moreover, conducting structural analysis through MICMAC method, it was tried to investigate the mutual effects of these variables on each other and identify the key drivers of what might form the future of this province. The important variables effective on the system were identified using library research, virtual space monitoring, surveying citizens, and future-related workshops. Variables were prioritized using importance and lack of certainty criteria. Then, the most important ones were fed into the direct effects matrix, and after completion with Delphi method, they were fed into MICMAC software. The outcome of the software was compared with the results of Dimtel method, and finally, the variables of the performance of organizations, balanced development, performance of land use plan, various types of tourism, and attention to water and environment were identified as the most effective variables in the formation of the future of the province.
Mostrar más [+] Menos [-]Assessing the Ecotourism Development Capability in Rural Areas With an Emphasis on Local Risk-Taking in Decision-Making: The Case Study of Mazandaran Province Texto completo
2021
Rezvani, Mohammadreza | Nickravesh, Fatemeh | Darban Astaneh, Alireza
Today, ecotourism is deemed a key industry and is granted a special position in the economic development of different countries. This industry has always faced risks in making decisions about selecting places with high ecotourism potential. Therefore, the purpose of this study was the assessment of ecotourism development capability in rural areas, with an emphasis on the environmental risk-taking in decision-making. In this study, 12 spatial criteria were used. Ordered weighted average (OWL), analytic network process (ANP), TOPSIS, and sensitivity analysis were used to assess the concept of decision-making risk, calculate the weight and importance of the criteria, rate the appropriate villages, and assess the modeling precision, respectively. The results showed that among the used criteria, the distance from the built lands and the distance from faults have the highest and lowest weight, respectively. With the increase and decrease in the risk-taking degree, the high potential class space increases and decreases, respectively, such that in the risk-taking degree of 0 or less, less than one percent and in the risk-taking degree of 1, thirty-five percent of all lands of the area fall in the “very high potential” class. The examination of the appropriate villages in the 0.5 risk-taking degree for ecotourism development showed that among all Mazandaran province villages, only 55 villages are in the “very high potential” class. Among these, Aali Kola with the relative distance of 0.8505 is the most capable village for ecotourism development. Finally, the results of sensitivity analysis revealed the adequate stability of the model results in various scenarios, i.e., the high reliability of the model results.
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