SPATIAL SCOPE AND THE LAYER OF NANJING’S ECONOMIC HINTERLAND BASED ON BREAKING POINT THEORY

The research on central city and its hinterland is one of focuses in city geography field all the time.Firstly,by building the index system and applying the method of principal component analysis,the central-strength values of cities were calculated.And the central-strength was used in place of city population index in breaking point theory.Secondly,by combining with weighted Voronoi diagram,both the spatial scope of economic hinterland between Nanjing and its competitive cities that lie outside Nanjing economic zone and the one between Nanjing and its surrounding cities were sketched.And by applying the demonstration method,the theoretical scope of economic hinterland was adjusted according to the real situation of economic contact,administrative district,natural factor and so on.Lastly,according to the strength of economic contact,Nanjing’s economic hinterland was divided into six layers of economic center,daily hinterland,direct hinterland,indirect hinterland,limited hinterland and competitive hinterland.The result showed that the shapes of the two economic hinterlands are both similar to the shape of‘■’,but Nanjing lies in the east of the former hinterland and in the center of the latter hinterland.The research on the spatial scope and the layer of Nanjing’s economic hinterland is helpful to the rational spatial organization of Nanjing economic zone and the rapid expansion of the influence from the Yangtze Delta area to the north-west region.