Spatial analysis of special-physical development process of settlement in the periphery of Tehran Metropolis- case study Islamshahr and Rubatkarim Area

Centralization and lack of efficient spatial planning approach from the 1950s is causing polarization of spatial developments in Iran. Tehran as the capital of the country and due to its diverse and important functions has experienced more polarization in this process. This process widened the development gap between the core and periphery areas and caused migration to the core, particularly to the region and city of Tehran. The poverty and marginalization of the migrants in the periphery areas formed the unauthorized settlements in these regions. This process overcomes the local, regional and national planning and management efforts. The Slamshahr-Robatkarim region is one of the periphery settlement areas of Tehran located in the southwest of the city. In fact, this study was conducted in response to the fundamental question: how did the process of settlements’ spatial structure develop during the period 1976 to 2015 in Slamshahr-Robatkarim? The hypothesis of this study is that it seems that migration from outside and political fragmentation from inside created the periphery and fragmented spatial structure of the peripheral environment in the study area. The study employed a qualitative, descriptive and analytic approach using secondary data, particularly the Landsat satellite images. The ENVI, ARCGIS and QGIS software were used for analyzing the data. The sampling population was the urban settlements in this region.

The findings of this study indicate that the Slamshahr, Golestan, Nasimshahr, Robatkarim, Salehabad and Nasirshahr have experienced the highest to lowest physical development between 1976 and 2015, repectively. Consequently, the agricultural areas were diminished rapidly in this period due to the expansion of population centers to the farmlands. Urban settlements studied in this research (Slamshahr, Golestan, Nasimshahr, Robatkarim, Salehabad, Nasirabad) have exhausted spatial-physical rapid growth trend and population from 1976 to 2015. This process caused swallowing and digestion of agricultural land and the formation and development of cities. Thus, the number of villages located in the study area (Slamshahr-Robatkarim) fell from 125 units in 1996 to 72 units in 2006 and 2011. In addition, the study area of ​​one town in 1976 grew to ten cities in 2011. In other words, about 53 villages became part of the integration process or developed into new urban areas from 1996 to 2011. This area was therefore faced with agricultural land changes turning them into to sprawl settlement between 1976 and 2015.

This process involved numerous internal and external causes such as favorable water and soil resources, communications road of Tehran-Saveh, proximity to Tehran, creation of jobs and manufacturing industries, plentiful and cheap labor, and regional and local divisions and weakness. However, immigration is the most important external factor in this process in this area. The process of centralization and polarization influenced the development of Tehran and its adjacent areas. In addition to migration as external factors, political fragmentation was the most important factor in spatial-physical process of change within the study area. This segregation or lack of structural integrity and functionality between Tehran state administration, Karaj Province, Ry province, Tehran provinces and the city of Tehran has been more severe in the decades 1961 to 1991. Land value of Slamshahr and Robatkarim was low during this period. Power and local political administration was poor in this area leading to provision of informal relations in the course of land-use in this area. However, after this period, the price of land and housing increased in Slamshahr and Robatkarim. During this period, immigrants moved to controlled remote locations from the city. Secondary settlements established immigrants (Nasimshahr, Golestan, Salehabad and Nasirabad) at this stage.