Centralism and Accelerated Spatial Land Use Changes in Metropolitan Tehran's Suburbs

Centralism and governments’ support in favor of one or some large cities, particularly capital cities, causes excessive concentration of population and activity in them and dramatic land changes in the land use of the suburban areas. Tehran, a primate city being politically and economically dominant and absorbing the social surplus from other cities, is among the capital cities which has attracted to itself a flood of rural and urban immigrants. It, having the highest rate of annual population growth in Iran, has been changed in terms of its historic-spatial order as a result of its unprecedented expansion into the outskirts. Due to the fact that land use change in the suburbs of metropolises and national capitals, being influenced by differing political, economic, and cultural conditions, has not followed a single trend or pattern and studies done on metropolitan Tehran, have not pinpointed the trend, extent and pattern of these land use changes, the following study seeking to bridge this gap employing telemetry, GIS techniques and documentary studies, land use development in light of centralistic policies in metropolitan Tehran was investigated. The results of the current research show that despite the decrease in the average annual population growth in Iran and metropolitan Tehran which is similar to developed countries, land use pattern has been different and dissimilar. Discontinuous spatial expansion of the settlements in Tehran's outskirts was evident and the roots of this expansion can be traced back to concentration of population in metropolitan Tehran, natural limitations, and spatial control policies. Expansion in these areas has, on the one hand, destroyed fertile farmlands and, on the other hand, posing structural, social and economical problems, has dismantled sustainable urban and rural development. Reaching sustainable development of the spatial system in such areas necessitates decentralism of activities and services from Tehran metropolis based on the potentials of other provinces.