An Analytical investigation of the Urban Hierarchy of Kurdistan province and its changes by using the Rank- Size Rule and Adjusted model of Behforooz

This Study investigates the urban hierarchy and its changes in Kurdistan province during 50 years ago. The research which has used descriptive-analytical method, begins with two essential questions that; what is the current Patten of urban hierarchy considering the urban places in the province? And can we detect a sign of primate city? The method used here is based on the application of "four city index" and "the rank-size adjusted model of Behforooz". According to the Behforooz adjusted rank-size model and the log distribution of rank-size the following results were obtained: the primate city character is the main feature of the urban network from 1956 to 2006 which the city of Sannadaj had 65 percent of the population of the province in 1956 i.e. 3 folds of the second city. But the urban system of the province experienced a more balanced transition in the recent years and now the primate city character of Sannadaj does not harm the other cities of the area. The study revealed that the establishment of 11 new towns in between 1996 to 2006 had an effective impact on the city distribution. So investment in smaller urban centers can maintain the present situation or distribute population to other urban places.