Assessment and evaluation of the differentiation Status and heterogeneity of spatial available in the urban area of Tehran using TOPSIS model

Compared to the statistics of the past four decades, the population of Tehran has almost doubled, but the population of the Tehran urban area has more than nine times, the rapid expansion of the region without a specific pattern and program has exacerbated undesirable effects, including has been increased regional differentiation and Spatial heterogeneity. The purpose of this research is to attempt to expand spatial justice in Tehran's urban area by reducing the differentiation and interstial Spatial heterogeneity. The present study paid to assessment of the degree of development in district settle ment by reviewing the 7 main criteria including 31 indicators .In data
analysis in addition to using statistical methods and TOPSIS, it was used Shannon Entropy method to weighing the indexes and The Arc.GIS software prepare maps. The results of the research show that the city of Tehran was in the first cluster alone and in the integrated measure, the degree of development and with the score 0.782 is about 3
times the settlements of the second cluster, Thats mean, Islamshahr, Shahre Qads and Karaj, was 15 times the settlements of the fourth cluster ,Pishva, Firoozkooh and
Baharestan, on the last.This topic indicates a very high concentration of developmental criteria in Tehran and proves the existence of inequality and extreme spatial heterogeneity between city Tehran and other settlements located in Tehran's urban area. It seems that adopting policies derived from the multi-centered development model and attempting to promote the developmental indicators of the peripheral settlements in Tehran can led to reduce the differentiation and spatial heterogeneity and expand spatial justice in the region.