Analysis of Temporal and Spatial Movement of The Gravity Center of City Industry:A Case Study of Tianjin

Regional gravity center model can measure the dynamic development course of economic attributes and the regional differences intuitively and accurately.By using the population and total industrial output data of Tianjin from 1989 to 2009,the method of measuring gravity center is established,from which we could analysis the temporal and spatial evolution path of the gravity center of industry comparing with the location of population-gravity-center,to accomplish the empirical research.The paper finds out the regularity of the industrial variation in each area or county,and the factors that influence the migration of industrial gravity center are listed.The results show that the gravity center of population moves slowly in Beichen Area,while gravity center of industry moves to Dongli Area in the southeast direction in 21 years,and the imbalance in the direction of east-west is significantly higher than that of the north-south direction.Location,government policies,industrial structure are factors that can affect the distribution of industry and cause the movement of the center of gravity.