Analyzing the role of immigration in the spatial - physical development of the city of yasouj(1345- 1385)

The problem of exceedingly immigration of cities has nestled in increasing the urban population and irregular physical development of cities including yasuj. Yasuj has been ranked the first city of getting immigrations in 1385. with regard to its administrative centrality on the one hand and the injection of governmental budgets and severe deprivation of other residences especially villages and small towns on the other hand, it is predicted that the trend of getting immigrations will continue in the years ahead and bring about unemployment, service and facilities shortage, false job, suburbia, social abnormalities and disorderly physical- spatial development. The main objective of this paper (investigation) is to confirm the role of immigration in the physical- spatial development of yasuj. For this to be done, the descriptive method has been applied. So the method of total number assessment of immigrations during 1345- 1385 has been used. To achieve this goal the geometric population increase has been applied. The results of the investigation show that immigration have had 83/4 increasing rate during 1345- 55 and also had been the most important in the population increases and the physical- spatial development of yasuj in 1365, 1375, 1385 respectively with percentages of 57/3, 66,76