Spatial pattern of urban spheres of influence in China and its changes, 1990-2007

Taking almost all cities in China(including Hong Kong and Macau) as the research object in the year 1990, 2000 and 2007, this article studies the urban spheres of influence by using gravity model. Based on overall grasp of the spatial pattern of Chinese urban spheres of influence, the spatial characteristics of urban agglomerations are paid close attention to. Urban agglomerations are national core competitive units, also they are the aeras with population and economy of highly gathered. The previous study of urban agglomerations mainly focused on the aspects of development stage, hierarchy, compactness, etc. From the viewpoint of urban spheres of influence, this paper brings forward four types of spatial pattern of urban agglomerations: namely, strings of beads, pieces of rags, semi-strings of beads, and semi-pieces of rags. Then some basic features are discussed such as cities’ numbers, population and central cities of urban agglomerations by using GIS and statistics method. Major findings are as follows: different spatial patterns of urban agglomerations have different degree of development and structure, and evolve under external policy and location factors. The spatial types of urban spheres of influence in China are generally stable, and the developing trends vary with different region and policy.