Spatial Analysis on the Sustainability of the Urban network in Ilam Province with Emphasis on the role of Small Cities

The formation of balanced pattern of urban network based on the small cities is a basic step for suitable distribution of facilities and services and leads to a spatially arranged distribution of the population and human settlements on the national scale, as well as, with the forming of such cities, the chain of big cities, towns and villages will be completed. The purpose of this research is to investigate and spatial analyzing the status of the urban spatial system of Ilam province in the periods from 1355 to 1395 by using the evaluation models of urban system analysis such as; Ziff's rank- size law, adjusted rank- size model, entropy coefficient, Lorenz curve and Gini coefficient, two-city index, Mehta index, first city concentration index, Herfindahl concentration index, Henderson centralization index. The method of collecting information and data was done using the non-field method; a library based on the necessary data from Statistical Centre of Iran between 1355 to 1395 years. The results of the research shows that the spatial system of the cities of Ilam province has an unbalanced pattern; the low role and position of small cities in the urban hierarchical system of the Ilam province despite low population and high numbers of small cities, the superior political-administrative position of Ilam city are the most important characteristics of urban network of ilam province. These factors cause to move of population from small towns to Ilam city to access the few facilities and services available in Ilam city, therefore this factor has exacerbated the gap in the hierarchical system of Ilam province between small-towns and Ilam city. Interventional actions of the government in order to strengthen small towns through increasing provincial credits in order to strengthen small cities and develop educational, health-care, infrastructure, IT technologies, road infrastructure, creating job opportunities, housing development, decentralization Administrative and political orientation are the most important solutions in order to adjust the urban system of the province.