The Geographic Area and Spatial Structure of Changchun Metropolitan Area

Metropolitan area is a geographical unit which composes of central city and surrounding areas where has highly social and economic integration with the central city. It is generally defined the city center as the core, with the convenient traffic communication as the basis. The economy and diffusion of information in metropolitan area remains highly complex and interconnected. The metropolitan area can integrate more resources,including human resources, material resources and financial resources. So, the metropolitan area is a regional integration entity which is limited by the convenient degree of daily commuting. Defining geographical boundary of metropolitan area is the foundation of metropolitan region research. Defining spatial scale of metropolitan area reasonably is the key to ensure that the resources, infrastructure and land use in central cities and surrounding towns can be integrated in order to achieve the harmonious development between economy and society. Changchun metropolitan area is the central region of Changchun-Jilin-Tumen Forerunner Area, with basic characteristics of the embryonic form of metropolitan area. Construction of Changchun metropolitan area is of great significance for promoting the urbanization level of the central area of Jilin Province and the northeast area of China, coordinating social contradiction, and boosting the overall economic development. This article uses modern defining techniques about city circles, in consideration of daily live circle, to define the city center in Changchun. On this basis, the relationship between surrounding towns and central cities of Changchun metropolitan areas is verified using indexes such as economic distance, gravity model and commuting rate, and at the same time metropolitan area and spatial structure of Changchun metropolitan area are delineated.Changchun metropolitan can be divied into core layer, close circle circle, opportunity circle based on the relation of central city with the surrounding area.Through the construction of metropolitan area, the main expectation is to dilute the administrative divisions, protect green open space and land resources, construct compact city morphology and relatively disperse functional areas, and actively implement the policy of national new-type urbanization.