GIS based analysis on the population migration of main nationalities in Gansu province since the founding of China

This paper sets up 5 Census database in 1953,1964,1983,1990,2000 based on GIS. The population gravity centers of main nationalities were calculated using gravity model in 1953, 1964,1983,1990,2000. Then, the characteristics and the influence factors of the moving of the minority population are analyzed. Study results show that population gravity center move to capitals are obvious. The move velocities of minorities' population gravity centers are slowdown, while the move velocities of HAN is Accelerated. Movement distances of east-west direction are generally greater than that of the north - south direction. The population gravity center are continued moving to southeast all the while. Finally, the factors of Natural conditions, Economic development, Policies as the mainly reasons were discussed.