A Study on the Spatial Process for the Evolution of Urban Agglomerations and Optimal Land Use
城市群演化的空间过程及土地利用优化配置

The evolution of urban agglomerations includes many contents, such as population, industry, type of cities, function of cities and so on. The most comprehensive and direct expression that urban agglomerations evolve is spatial process. Urban agglomerations can be divided into three layers, namely, primacy urban belt, growth belt of urban group, and hinterland belt of urban agglomerations. The evolution of the structure follows the laws of urban growth and regional economic development. The spatial dispersion of urbanization is the beginning of spatial spreading about urban agglomerations. The spreading of urban agglomerations has four phrases, namely, the expanding phrase of multi-central cities, the directional sprawl phrase of urban space, the centripetal and centrifugal phrase between cities, and the complex expanding phrase in urban agglomerations. Concentration of industries and evolvement of industrial structures are immediacy powers of spatial expansion of urban agglomeration. There has a close connection between urban development and land exploiture. Economic development brings about land exploiture, suburbanization and the growth of urban agglomerations promote land exploiture, and construction of developing region brings land exploiture. At the same time, urban spatial growth promotes land increment. This paper analyzes the spatial process for the evolution of urban agglomerations, studies its dynamic mechanism, and describes its basic features and regulars from the structure of urban agglomerations, space of urban agglomerations and land-use of cities. At last, the paper reveals the connections between the evolution of urban agglomerations and the changes of land use as well as its development trends. That are growth axis and expanding diversity (including type, speed and direction).