Regional Planning
Hashem Dadashpoor; Nariman Jahanzad; Homa Jalili
Volume 5, Issue 18 , May 2016, , Pages 51-62
Abstract
In the last few decades, city-regions have faced considerable changes. Mashhad metropolitan region as one of the most important development centres in the eastern region of Iran, has experienced great spatial changes which have brought about many spatial problems. This city alone has more than 75 percent ...
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In the last few decades, city-regions have faced considerable changes. Mashhad metropolitan region as one of the most important development centres in the eastern region of Iran, has experienced great spatial changes which have brought about many spatial problems. This city alone has more than 75 percent of the population of the wider Mashhad region as well as accounts for approximately 90 percent of the added value of that region. The explanatory indices used in this area indicate an intense imbalance and centralization of capital and power in the area. The logical consequence of this imbalance have led to urban sprawl and increasing accumulation of capital. This sprawl have had several consequences such as the destruction of green and agriculture lands, land speculation, increase in environmental pollutions, ecological destruction and mismatch of the developed land with the natural potentials of those lands. On this basis, it is necessary to identify the future spatial changes in this region. Accordingly, this study has two parts. The first part is based on the morphological dimension of spatial structure and simulates future land use changes for the years 2026 and 2041. In doing so, the CA model was associated with ANN algorithm. The simulation process was run in QGis 2.4 environment. In the second stage, by using distribution, clustering and concentration indicators and based on the predicted data of population and employment in the aforementioned years, the spatial configuration of the region was drawn. The results of distribution indices show that from 1996 to 2041 the value of entropy coefficient will decreased which indicates polarization of the population and employment in the region. The findings of the spatial changes analysis by K-Ripley function indicate that at short distances, population and employment distribution will change in a dispersing manner, and at long distances, concentration in population and employment will be intensified. Finally, concentration indices show that the Mashhad metropolitan area does not have any spatial concentration patterns, and population and employment will distribute randomly. The results show that the growth process in the region is proceeding in a devastating manner as vast amounts of agricultural lands and pastures will continue to be ruined. In the year 2026, 247 Km2 of these lands will be built on and green spaces will tranform into urban lands. This amount will be equal to 1004 Km2 in the year 2041.
In conclusion, the continuation of the existing growth will lead to irreparable consequences in the area.Future spatial changes will lead to consuming agricultural lands and grasslands and will deteriorate rural settlements. The continuation of the present development of urban settlements and land-use changes might cause environmental disasters such as a water crisis, increased air pollution and pressure on infrastructure which. in turn will lead to irreparable socio-economic damage and human crises like riots, crimes and vandalism. Thus, it is necessary that planning systems pay attention to reasonable management of growth.
Urban Planning
Hashem Dadashpoor; Sepideh Tadayon
Volume 4, Issue 14 , May 2015, , Pages 61-76
Abstract
The emergence of metropolitan areas is a phenomenon of the twentieth century and is a continuation of the prevailing trend of urbanization at the beginning of the eighteenth century. These new forms of urban areas are not only greater than previous ones in scale and more associated with decentralization, ...
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The emergence of metropolitan areas is a phenomenon of the twentieth century and is a continuation of the prevailing trend of urbanization at the beginning of the eighteenth century. These new forms of urban areas are not only greater than previous ones in scale and more associated with decentralization, but qualitatively they are included in various types of systems. These new urban forms reflect fundamental structural dynamics that have changed the geography of urban areas. Different patterns of displacement can be the result of various factors including housing, employment and income levels, the factors that lead to different types of spatial mobility. In fact, depending on the degree of deviation from the consent of the provider of such elements, spatial mobility and displacement occurs in other areas. The impact of housing, employment and the ability to take advantage of the services required is very important and effective on formation of different spatial patterns. The Tehran metropolitan area including the city of Tehran and the surrounding population, economic and services centers has created a unique market for employment and residence. With regard to the distribution of housing, employment and services, various types of spatial mobility and travel patterns are emerging. The main objective of this research is identifying homogeneous areas in Tehran metropolitan area based on the number of flows and their convergence. By identifying and analyzing the characteristics of these zones, we can identify the flow conditions of spatial mobility and relations between the zones in the area and planning for it.
The method used in this research is descriptive - analytical. In order to identify homogeneous zones, two elements, spatial mobility and physical links were considered. According to the available data, the most important of data is the origin-destination flow of people’s trips and to achieve the desired objectives, network flow analysis method was used. Thus, to identify homogeneous areas and to discuss spatial mobility trends in Tehran metropolitan area, network analysis features and fraction analysis - as a network analysis tool- was used. In addition, in this study, the characteristics of each zone were based on the calculation of the network including centralization and power, and how the presence or absences of certain central cities in each category are determined.
Based on fraction analysis as a tool of network analysis, three main groups were identified in Tehran metropolitan area. The first category encompasses Tehran and Karaj metropolitan areas as well as the Central, South and Southeast cities in the region. The second category covers the north and northeast cities and the third category includes western most cities in the region. The zones comprise of cities in the region based on their distance from each other and their roles. The flow conditions are not similar across the area; the first zone, Tehran mega city and Karaj metropolitan, as central points have been allocated the maximum amount of connections and mobility and have also established stronger links with other zones. However, eastern and western zones have not been able to create considerable ties due to their great distance from each other. Tehran metropolitan area in addition to having a population of several million and a great deal of economic activities has a high level of functional linkages. Karaj metropolitan area has many economic activities in the form of manufacturing industries and factories based within it, and thus make the area an important place. The centers of Tehran and Karaj are attractive for travel from all over the metropolitan area while travel in other settlements occurs on a more local level. Most towns’ sphere of influence do not exceed the respective border city.
Dependence on Tehran and then Karaj, shows the unbalanced system of movement and mobility in Tehran metropolitan area, while structural-physical changes in the current situation depends on new image of the area, mainly a mix of links and nodes and also emphasis on looking more and more integrated into the centers and areas in the form of a network of settlements. By identifying types of trips and their orientation, travel management can reduce the degree of concentration and amount of damaging trips. In addition, unnecessary trips can be eliminated through the development of communication technologies and network facilities and services and trips in the area can be planned in a balanced system.
