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Evaluation of Landscape Structure for Development and Integration of the Protected Areas
2019
Sadegh Oghli, Roghaye | Jahani, Ali | Alizade Shabani, Afshin | Goshtasb, Hamid
Integrity and connectivity of habitats are among the important factors for the conservation of plant and animal populations within protected areas, particularly when the habitats are connected. Investigating on the integrity of these areas could help interconnecting islanded patches and preventing the negative impacts of fragmentations. This study aimed to quantify the fragmentations of different regions within the protected area of Jajroud. Land-use map was extracted using remote sensing (RS) and geographic information system (GIS) techniques. The acquired data were employed to study the fragmentation of the regions considering the landscape metrics. The results indicate that the northern parts of the region, including the national parks of Khojir and Sorkheh Hesar, in general, possess larger patches and a higher level of connectivity, while the southern part is tending towards small-grain structure. In addition, results support the applicability of landscape metrics in assessing the management of the protected areas and identifying the protection patches in order to prioritize the protection of landscape patches.
Показать больше [+] Меньше [-]Evaluation of Employment Distribution Effects on Urban Network Transformation in Isfahan City-Region by Employing the Social Network Analysis
2019
Rastghalam, Niloofar | Moradi Chadegani, Daryoush | Shahivandi, Ahmad | Mohammadi, Mahmoud
Relationships between urban network cities are shaped by demographic trends and the factors affecting it. This research, using two concepts of occupation distribution and urban network, seeks to study the effective factors in the occurrence and intensification of inequalities in the Isfahan city spatial network. In the same way, the changes and transformation of the Isfahan network (including 37 cities of Isfahan approved by City-Region Plan) are considered by employment indicators as well as distance between cities, using network mapping in social network analysis software (Gephi) in three periods: 1996, 2006, 2016. The research method is applied in terms of purpose and application. The data were gathered through library studies and review of documents. The data analysis method is also quantitative. For employment at any time, a separate network is mapped and analyzed. The results indicate that in Isfahan city network at the time of research, demographic changes in populated cities and low population centers do not directly correlate with the shift of employment in the urban network, while there is a direct relationship between cities with a moderate population and the flow of employment. In addition, the metropolis of Isfahan, with a significant percentage of facilities, resources, financial flows, political power, and population flows, does not have decent employment flows rank in urban network cities.
Показать больше [+] Меньше [-]Zoning the Risk of Flood in Birjand
2019
Saberifar, Rostam | Shokri, Homer
Physical expansion of cities, particularly those that have experienced unusual growth due to economic, social, and political transformations, has led to numerous problems. To this end, the purpose of this study was to investigate conditions of Birjand City regarding flooding and hazard zoning caused by this important natural event. The present study is applied regarding the objective and descriptive-analytic considering its methodology. The study was descriptive-analytic and performed through prediction of the scope of damages caused by floods and based on hazard zoning. Data gathered regarding land use, population density, features of existing watercourses, slope, residential and population density, CN coefficient, runoff, the age of buildings, open spaces, and other influencing components. Collected data were weighed after correction and conversion, and required maps were prepared after conducting paired comparisons and determination of eventual coefficients for each layer. AHP model and associated software, particularly Expert Choice, and ArcGIS, were used to determine final weights and coefficients. According to the results, given that development of Birjand City has been done on the sub-basin of the existing watercourse, all the city is exposed to the risk of flooding. However, southern and southeastern zones with almost 20% of the city area are subject to high and very high risk; northwestern and southeastern with 50% of the area are subject to average risk; and other zones of the city with less than 30% of area are subject to low and very low risk. As a result, the operation of flood control and flood warning systems in areas with greater vulnerability should be considered, while illegal occupation of flooding basins and watercourses should be dealt with.
Показать больше [+] Меньше [-]The Analysis of Structural Landscape Changes in Tabriz City Using Landscape Ecology Principles with an Emphasis on the Connectivity Concept
2019
Mahmoudzadeh, Hassan | Masoudi, Hassan
Urban societies are complex landscapes that face unbalanced and exogenous growth and are rapidly changing as a result of population growth and urbanization. That is to say, non-urban, large swaths of land are consumed by cities and urban settlements, and over time they are fragmented into smaller pieces. Therefore, the present study was designed to detect and evaluate changes in the landscape structure of Tabriz metropolitan area and to evaluate the performance of landscape metrics in analyzing changes. To this end, first the land use maps for 1984, 2000 and 2018 were prepared using Landsat satellite imagery. Then, in order to analyze the changes, a combination of Landscape metrics including NP, CA, PLAND, LPI, ED, MPS, LSI, and COHESION was computed at two levels of land class and landscape using Fragstats4.2 software. The results showed that the lands used for urban settlement during this period have had the most changes and growth, in contrast to agricultural farms, gardens and green-space which have had a downward trend and have been converted to other uses. Also, the number and density of patches have increased over time, leading to the fragmentation of the landscape. On the other hand, the average size of patches belonging to constructed lands and agricultural and horticultural lands respectively increased and decreased, and caused more distortion and complexity of Tabriz city landscape through an increase in the landscape shape index. In general, the analysis of land use maps and landscape metrics clearly reveals the effects of human activities and urbanization on the surrounding environment, and the results indicate that the landscape of Tabriz has got more granular, more complex and geometrically more irregular. Then, with this decreasing connectivity, it has become more fragmented.
Показать больше [+] Меньше [-]Explaining the Pattern of Regional Development through Activity Clusters in Tehran Province with an Emphasis on Competitiveness
2019
Tabatabaee, Soudeh Sadat | Saeideh Zarabadi, Zahra Sadat | Ziari, Yousef Ali | Majedi, Hamid
Due to the consequences of globalization, regional development, which has always been highly important in macro planning, requires new approaches that are flexible about regional change. Among these consequences is the emergence of powerful regional economies with high GDP that have drawn the attention of many planners to the concept of competitiveness. Using recently proposed approaches and the important aspects of the global economy, this study set out to explore this concept at the area level. The purpose of this study was to analyze movements and structural-functional relationships in order to develop a local pattern of clusters in Tehran province. This study was a developmental-applied research project in terms of purpose and an analytic-descriptive one in terms of methodology. The data collection was based on document analysis and library studies and the data was collected through note taking, available statistics, and documenting. Data analysis was carried out using cluster analysis and specialized index methods, and the results were used in identifying activity clusters after examining the natural capability of each county. The results of the analysis show that the pattern of activity in Tehran province is the metropolis-dominated cluster pattern, and the counties which are located in the province can be identified in the form of 5 regional-local clusters. The above mentioned clusters of activities can provide the basis for regional development in Tehran province by joint and purposeful planning based on the priorities offered in this article.
Показать больше [+] Меньше [-]Analyzing the Urban Network Morphology through Balancing of Space Approach: A Case Study of the Urban Network of Hormozgan Province
2019
Moshfeghi, Vahid | Jafari, Yahya | Alizadeh, Hadi
Balancing the Spatial structure and determining the future urban network are the fundamental missions of spatial planning. As the main organizing elements of space, cities are organized within the urban network form. Urban network is assessed based on the agreement between form and function dimensions. The effectiveness of various models can be investigated through an analysis of their relationships. Accordingly, the study at hand has been carried out to analyze the urban morphology in order to accord the morphological and functional dimensions of Hormozgan province urban network. The study is applied in terms of purpose and descriptive-analytical in terms of methodology. The analytic indices of the study for Hormozgan province urban network morphology include road network, the distance between settlements, urban population, and types of services. The analytic instrument for the attainment of the purpose of the study is the Inward Distance Weighted (IDW) model within ARC GIS 10-4 software. The obtained results show that Hormozgan province urban network morphology follows four patterns, namely mono-centric, polycentric, linear and isolated. The location of these patterns in the province indicates the relationship between the location and the network morphology. As the large cities of the province are located near the sea, the mono-centric and polycentric patterns have been formed under the influence of the sea factor. However, the isolated and linear patterns are located in both the islands of the province and the mountainous areas or intermountain plateaus. Ultimately, the study shows that the lack of agreement between the form and the function weakens the connection and interaction of the interconnected areas. This lack of agreement reduces the fulfillment of the urban network’s use of neighboring opportunities and decreases the network effectiveness.
Показать больше [+] Меньше [-]Assessment of spatial vulnerability infrastructures in Yazd province, with passive defense approach
2018
Razavian, Mohammad Taghi | Alian, Mehdi | Rostami, Hossein
Nowadays, infrastructures play a significant role in the safety process in ordinary times and during the crisis. From this point of view, maintaining the safety of infrastructure against threats would be a security priority for any country; therefore, understanding current situation and vulnerability of infrastructures in a regional scale can be used as an efficient mechanism to formulate regional and national security strategies. This paper assesses the vulnerability of infrastructures with passive defense approach and analytical method, in Yazd province. The analysis of data and information collected were done with analytic network process model (ANP) and geographic information system (GIS) due to the interaction between infrastructures. The results showed that about 51 percent of province area is in the situation of high and very high vulnerability. The central part of the province, Yazd and Meybod, is the most vulnerable regions, because of their failure to comply with principles of passive defense, favorable environmental conditions, further concentration, centralization of infrastructure, and political, administrative, and geographical centrality.
Показать больше [+] Меньше [-]Scenario Development in Realizability Territorial Spatial Arrangement (Case Study: Khorasan-e-Razavi)
2018
Mousavi, Mir Najaf | Ghaderi, Reza | Taghilo, Ali Akbar | Kahaki, Fatemehsadat
Future studies in Territorial planning focus on finding key factors, drivers and uncertainties in the development of regions in the planning space. This is in the way that the planner can map and manage a desirable future by having them as a control lever. The purpose of this study is to identify the effective factors on the planning of Khorasan-e- Razavi province, to identify the key variables of the province's development and finally to develop effective scenarios for the province's planning. The research process is practical in terms of purpose, and the research method is descriptive-analytic. The nature of the data is qualitative. The data are collected through survey and from documents and records. Data analysis is based on futures research techniques including environmental scanning, structural analysis, and cross-impact analysis. The results of the research show that among the developed scenarios, province planning will face 22 strong adaptive scenarios, 2740 weak adaptive scenarios, and 1837 inconsistent scenarios, in the future. Of the 22 possible scenarios, eight scenarios have a favorable status, two scenarios have interstitial status, and 12 scenarios are in an unfavorable situation. Between the favorable scenarios, Scenario 1 is the best and the most likely scenario ahead of the province and all of its possible probabilities are quite desirable.
Показать больше [+] Меньше [-]Ecological impacts assessment of land use change on the natural structure of the Gharesoo Watershed
2018
Mehri, Azade | Salmanmahiny, Abdolrasoul | Mikaeili Tabrizi, Alireza | Mirkarimi, Seyed Hamed | Sadoddin, Amir
In order to evaluate the impacts of land use change, the quantification of landscape structure through relevant metrics can be used. These metrics are appropriate owing to the fact that they are measured easily and take low cost and time. The goal of the present study is to investigate the ecological impacts of land use change on the natural structure of the Gharesoo Watershed in order to identify the highly affected areas. Firstly, the amount of land use change between 1984 and 2013 was calculated. Then, landscape metrics were used to investigate the spatial patterns of land use change. Finally, an ecological impact index based on current land use was established. The results showed that during the period studied, areas of forest and agriculture have decreased by 12 and 5 percent respectively, and other uses including residential-industrial, rangeland, and transportations have increased by 292, 143, and 176 percent respectively. Landscape metrics analysis indicated a decrease in compactness and an increase in fragmentation and degradation of the landscape. According to the ecological impact index map, approximately 28 percent of the region is exposed to high and very high impacts. These areas can be used as a base for future studies and may be earmarked for intervention measures such as improving land management and decreasing fragmentation.
Показать больше [+] Меньше [-]Spatial patterns analysis of urban growth in Iran metropolitan regions (Case study: Tehran, Mashhad, Isfahan, and Shiraz metropolitan regions)
2018
Dadashpoor, Hashem | Salarian, Fardis
Residential and employment attractions urge the population to reside in regions with appropriate potentials for development. The metropolitan regions of Iran have been attractive centers for the population; this attractiveness resulted in some changes in different spatial patterns. The present research examines the effect of spatial-physical, and demographic variables on metropolitan regions of Iran in order to achieve suitable planning for future spatial development of Iran. The objective of the study is to analyze correlation, centralization, and uniformity of distribution and composition of spatial patterns of development in the metropolitan regions. To do this, Shannon entropy, spatial Gini coefficient, spatial density index, and Kriging Estimator were employed. The results showed a trend that dictates on a decrease in concentration in metropolitan regions, which has manifested in different spatial patterns. In Tehran metropolitan region, the trend of development goes into polycentric with sprawl in the peri-urban and rural area. According to the development trend of population centers in Tehran, it can be said that at the same time of concentrated centralization, other settlements have played an effective role in the spatial structure of this metropolitan area, and strong road network has led to the formation of such pattern. In Isfahan metropolitan region, the spatial structure has changed into concentration. This has happened with an unbalanced distribution to a radial pattern. While Mashhad metropolitan region has a monocentric linear pattern, Shiraz shows a monocentric and sprawl in the periphery. This can be attributed to the small growth of settlements compared to the metropolis.
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