关键词: 大都市区, 城市化, 逻辑斯蒂增长模型, 美国

Abstract:

Urbanization is now recognized as a ubiquitous phenomenon of global importance. Traditional studies of urban and regional spatial sprawls usually pay much more attention to the sprawl processes of urban land use and seldom take account of natural landscape fragments and deforestation in general. This study tries to synthesize these two spatial processes by employing logistic competitive model in a case study. The sprawl process in the metropolitan area of the Baltimore-Washington is a typical organic growing process among corridors. By the 1790s, the major growths of urban area were around several growth poles. By the 1890s, the urban growths had begun along several corridors between Washington and Baltimore. By the 1990s, the urban growth was along both the growth poles and corridors so called network growth. It totally connected major corridors between Washington and Baltimore in 1992. This process can be described as "point-line-net-surface growth". What is interesting about this analysis is that the metropolitan growth seems to have a 30-40 year cycle by using logistic modeling simulation and circling the spatial area in particular. The period cycles included the low-speed developing cycle between 1792 and 1852, from the high-speed to low-speed developing cycle between 1852 and 1932, and the high-speed with turbulences developing cycle between 1932 and 1992. However, the expansion of urban growth has suffered from increased environmental pressure because of limited environmental capacities. They expand over agriculture, wetlands, wildlands, and forests, thereby changing the physical shape of the landscape as well as the functioning state of the landscape ecosystem. To solve these problems, "Smart Growth" initiatives have been promoted since the 1990s by increasing urban forest areas and constructing rural ecosystems in the Baltimore-Washington metropolitan region. We use the logistic model by adding competitive indices to simulate this process. Therefore, from the historical experiences of the metropolitan growth, the "Smart Growth" of metropolises must be favorable for the sustainable development of China metropolitan planning.

Key words: metropolitan area, urbanization, competitive model, USA