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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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]The Identification and Analysis of the Strategic Variables Effective on the Future of Yazd Province Through a Structural Analysis Approach
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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Analysis of Spatial Form and Demographic Changes of Shiraz Metropolitan Area During the Period 1996-2016
2021
Nemati, Zahra | Dadashpoor, Hashem
The number and population of metropolitan areas have increased significantly during the last century, and in line with the increase in population, improved communications, global trends, and other significant factors, there have been many changes in the spatial development of these areas. These changes are observed in metropolitan areas of Iran during the same period, but there have been a few studies on the changes of these areas in Iran. In this study, the urban land density (U.L.D) function was used to investigate the spatial development trend in Shiraz metropolitan area from 1996-2016. The results show that the Shiraz metropolitan area has experienced a decentralized and scattered spatial form from 1996 to 2016. The pattern of changes in the region's spatial development during the years 1996-2006 and 2006-2016 shows that spatial development has become more decentralized and scattered. According to demographic analysis, the highest population density in 2006, 2011, and 2016 can be seen in the central buffer zone of Shiraz metropolis. Based on directional distribution (standard distance), the population distribution has moved to the northwest of the region. In addition, when analyzing the population distribution pattern, the Moran statistics shows that the region population is distributed in clusters. In general, the decentralized and dispersed spatial form and the formation of population clusters in the region's development process show an imbalance in the region's spatial and demographic development. Some of the significant effects of this phenomenon are urban fragmentation, social segregation, car dependency, and the destruction of agricultural lands and gardens.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Spatial Modeling and Prioritization of Potential Areas for Determining Location of Hospitals by a GIS-Based Multi-Criteria Decision Making Analyses: A Case Study of the 5th District of Tehran
2021
Zandi, Iman | Pahlavani, Parham
Hospitals are among the most essential human services whose role in the health of the citizens is very important. One of the important issues related to hospitals in developed cities is determining the optimal location for their construction. In this study, in order to select the optimal hospital location, a combination of expert opinions, GIS, and MCDM was used. For this purpose, 12 criteria were selected for the spatial modeling of the potential areas of hospital establishment, and then the weight of each criterion was calculated using the weighting method of Analytic Network Process (ANP). Then, a map of the potential areas for the hospital establishment was prepared and 11 sites in the potential areas were selected. In the next step, the weight of each criterion was determined again using Criteria Importance Through Intercriteria Correlation (CRITIC) method. Then, by the integration of two weighting methods, i.e., ANP and CRITIC, with two MCDM methods, i.e., EDAS and VIKOR, these sites were ranked. The results of spatial modeling showed that the western half of the district is more suitable for the construction of a new hospital than the other areas. According to the results of the ANP, the distance from hospitals, and according to the results of the CRITIC, the seismic vulnerability were the most important criterions in determining the optimal hospital location. Based on the ranking results coming from CRITIC-EDAS, CRITIC-VIKOR, and ANP-EDAS, the site No. 1, and according to the ranking results of the ANP-VIKOR, the site No. 8 have been the most suitable places for the construction of a new hospital. In the light of the results of the site evaluations by experts, CRITIC-EDAS and CRITIC-VIKOR methods are more accurate for hospital location selection.
显示更多 [+] 显示较少 [-]An Analysis of the Continuity and Cohesion of Urban Ecologic Network Through a Graph Theory Model
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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]The Description and Explanation of the Logistics Spatial Structure Changes and the Factors Effective on Them in Tehran Metropolitan Region
2021
Sadati, Alireza | Dadashpoor, Hashem
The purpose of this study was to investigate and analyze the logistics spatial structure changes and to explain the objective factors affecting it in the Tehran metropolitan region during the period 1986-2011. The research method was descriptive-analytical, and in order to achieve the objectives of the research, three analytical methods – including indicators of number changes, growth rate, as well as the relative rate of changes in population density – employed in the logistics sector of each geographical area were used. On the other hand, analytical methods for measuring the degree of spatial concentration such as Gini coefficient and spatial autocorrelation as well as multiple regression analysis were used to estimate the correlation of effective factors with the spatial distribution of the employees working in the logistics sector (as the independent variable). The results of the analysis show that from 1986 to 2011, the spatial pattern of the logistics geographical distribution in the Tehran metropolitan region was centralized, consisting of the logistics cluster of Tehran metropolis. That is to say, tracking the process of spatial changes showed the decentralization of the population working in the logistics sector of Tehran metropolis and the concentration of this working population in the western and southwestern geographical areas surrounding the metropolis. From 1986 to 1996, among the objective factors affecting the logistics spatial patterns of metropolitan areas, the spatial distribution of the population working in the logistics sector had a higher correlation with the spatial distribution of population and labor force. That is to say, the higher the number and density of population and labor force in the geographical area, the higher the population working in the logistics sector. However, from 2006 to 2011, the spatial distribution of the population working in the logistics sector had a higher correlation with the spatial distribution of the population and the literacy rate.
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