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Assessment of Shahre Rey Fragmentation Trend Using Metrics
2021
Foroutan, Sara | Shariat, Mahmoud | Kheirkhah Zarkesh, Mir Masoud | Sarvar, Rahim
Land use in Shahre Rey has experienced unprecedented growth in urban areas in recent decades. Land use changes affect social, economic, and environmental conditions. Gathering information about these changes is essential for better planning and management of urban areas in sustainable development. Consequently, the object of this paper is to better examine the Shahre Rey land use changes affected by urban development and to investigate urban landscape integrity using the 1988-2018 "Fragmentation" index. Moreover, it was intended to provide solutions for the determination of hot spots based on appropriate criteria. With the help of Landsat satellite images, four land uses – including urban landscapes, agricultural lands, green spaces, and barren lands – were extracted and the extent of land use changes was determined. In order to investigate the fragmentation of Shahre Rey landscape, the metrics of the number of patches, patch density, and the largest patch were used. Cross-Tab was also used in a part of the study. The results showed that the land use areas of urban lands and urban green space had increased by 369.7 and 55.6 hectares, respectively, while agricultural lands and barren lands had decreased by 213.8 and 211.5 hectares, respectively. In urban land use, integration had increased. In the green space and agriculture land uses, fragmentation has increased due to the creation and construction of roads. Based on the criteria of "position relative to borders and roads as well as the area and size of patches,'' solutions were made to determine the "hot spots" of vegetation and residential areas to help making plans for the improvement of their conditions. The reason is that land use change, especially the loss of vegetation, has a negative impact on the landscape.
Afficher plus [+] Moins [-]The Evaluation and Modeling of the Impacts of Urban Development on Landscape Patterns in Karaj Metropolis
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.
Afficher plus [+] Moins [-]The Evaluation of Geomorphologic Landforms for the Development of Human Settlements: A Case Study of Southeast Cities of Razavi Khorasan Province
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.
Afficher plus [+] Moins [-]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
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.
Afficher plus [+] Moins [-]The Feasibility Study of Areas Appropriate to Recreational-Sports Trekking in Dorud City
2021
Dehghani Firozabad, Leila | Mirsanjari, Mir Mehrdad | Ildoromi, Alireza | Abedian, Sahar
The identification of areas appropriate for the sustainable growth and development of touristic activities is among the main topics of tourism planning. With its positioning between a mountainous area and a plain, Dorud city enjoys topographic diversity and numerous natural attractions that need proper management and appropriate planning in order to attain the objectives of the sustainable development of tourism. Aiming at the examination of the potential of this area for recreational-sport trekking ecotourism, the study at hand set out to assess the ecologic power of this area using multi-criteria evaluation method. This study was applied-developmental in terms of purpose, and descriptive-analytical in terms of research framework. Since the identification and evaluation of tourism potentials is a multi-criteria decision-making question, five main criteria groups – including physical, ecologic, infrastructural-bodily, safety, and economic-social criteria groups – and 25 secondary criteria for the recreational-sport trekking tourism were developed. The weighted linear combination was used to integrate the criteria. Then, the final map for ecotourism activity in the region was drawn in three spaces with low, mid, and high capability. The results of the final desirability map showed that 6.9 percent of the area has high potential for recreational-sport trekking. Moreover, the results of TOPSIS revealed that Qarun and Oshtorankuh mountains are the first and second top ranking mountains for recreational-sport trekking, respectively. Overall, the results of this study demonstrate the appropriate areas for recreational-sport trekking, which can function as a guide for tourists, managers, and planners to make decisions and administer developmental policies in the light of environmental and socioeconomic approaches and considerations.
Afficher plus [+] Moins [-]The Provision of an Optimal Model for the Demarcation of the Protected Areas of Gas Transmission Operational Areas Using Spatial Allocation Method
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.
Afficher plus [+] Moins [-]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
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.
Afficher plus [+] Moins [-]Assessing the Ecotourism Development Capability in Rural Areas With an Emphasis on Local Risk-Taking in Decision-Making: The Case Study of Mazandaran Province
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.
Afficher plus [+] Moins [-]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
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.
Afficher plus [+] Moins [-]Modeling the Process of Spatio-Temporal Changes in Land-Use and Urban Development of Ahvaz Based on Spatial Planning Approach
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.
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