Characteristics of Spatial Structure Evolution and Mechanism of Urban Agglomeration in Sichuan Province

Based on the relevant statistics of2000-2015, and by use of the methods of statistic and GIS analysis, an ex- ploration was made into the spatial structural evolution characteristics of the urban agglomerations in Sichuan from the four as- pects of the population spatial structure, the city size distribution, the traffic network structure and the economic spatial struc- ture. The results show: the urban agglomeration network, which is based on the traffic network, has taken a basic shape; the scale structure of the urban agglomerations is rather complete while the primacy ratio of the cities is too huge; the development of small and medium-sized cities is rather satisfying and the development of big cities is relatively slow. The development of ur- ban agglomerations has undergone a long period of spatial polarization process, and gradually transformed into dispersed and balanced one. The spatial structure and its evolution of urban agglomeration are mainly affected by natural conditions, demo- graphic factors, transportation network, economic foundation and policy planning and so on.