عنوان مقاله [English]
Geography as a place and space science studies spatial distribution of phenomena and their relations in the earth surface. One of the important phenomena of human made is cities that their spatial distribution depends to variety factors. In past, environmental factors had more important role in cities locating than others, but now political variables are very important. In national scale, one of the important political factors is political system that is divided into unitary, federal and regional systems.
Iran’s political system is completely centralized unitary system that has been started from Reza Shah’s era. In this period, central cities of Iran have developed lager than their border cities.
This research tries to discover the effects of unitary political system as independent variable on spatial distribution and deals with development of Iran’s cities especially metropolises as a dependent variable. Therefore, the research questions are: how is spatial distribution of Iran’s cities? What are effective factors in spatial distribution of Iran’s cities? Why there is not any metropolis in boundary regions of Iran? Research method is historical and descriptive method and logic analysis. In addition, Arc GIS is used to address the research questions.
Results and discussion
A huge part of historical period of Iran coincide with decentralized political system and spatial distribution of power on the basis of semi-federal system of kingdom in ancient Iran and tribal system in median decades. This mechanism caused balanced development of country regions based on ecologic potentials. There was Iran’s urban network without a central metropolis. The cities just related with capital for political problems. In third decade of 20th century, Iran’s Political system changed to centralized unitary system. Reza Shah’s centralism politics caused core-periphery model. This model connected all national, regional and local affairs of country to Tehran. Capital was political, economical, commercial, industrial, cultural, educational center of country and through of Iran attracted a lot of immigrants. Tehran and its suburb have 18.9 percent of population and 25.4 percent of urban population of Iran. The rest of Iran’s territory except border regions has metropolis but it is not comparable with Tehran. Boundary regions and its cities cannot develop like central region although they have suitable environmental potentials. These regions have different ethnic, language and religious minorities. Moreover, under-developed neighboring countries and existence of NATO forces especially US forces in Iran’s neighbors caused militarization of boundary regions. These factors cause absent investment in infrastructural affairs in this region. So, boundary regions are under-developed.
The results show that the unitary and centralized political system caused uneven and injustice spatial distribution of Iran’s cities and regions. It is the most important factor creating polarized system and its consequence is core-periphery model in spatial structure of Iran's cities. So, the capital is core and boundary cities are periphery. The core is powerful, attractive and model to others and the periphery is inactive, passive, margin and located in the end of transportation lines. The rest of Iran’s territory (semi-periphery) is located between them. Semi-periphery is passive than core, but is powerful than periphery. The development indexes reduce when we are moving from core to periphery and vice versa.