1990年以来是中国社会经济改革全面展开的阶段,城市空间增长发生了较大的变化,本文以全国52个特大城市为样本,利用各城市1990,2008年影像图、土地利用现状图等数据,运用空间计量、拓扑结构图示等方法对城市空间增长特征进行了分析。研究表明:1990年以来中国特大城市空间在规模增长上表现出增长速度快且按人口规模等级顺序依次变缓,在要素增长上表现出新型化、多样化变化,在结构增长上出现带状化、多中心化转变,在形态增长上呈分散化、破碎化变化,城市空间增长方式以轴向式和跳跃式为主导,特别是2000年以来这种变化更加明显。工业化进入中高级阶段之后的快速经济增长、快速城市化以及政府GDP导向的政绩观是导致城市空间增长上述变化的主要原因。最后文章针对中国特大城市空间增长规模过度超前、结构松散、形态破碎的问题,提出构建以规模控制、结构优化及空间紧凑性为核心的节约型城市空间增长目标。
Since China's economic reform in the post-1990s, urban spatial growth has experienced tremendous changes. By using methods, such as spatial econometrics and topological analysis, this paper analyzes the features and causes of spatial growth in 52 Chinese metropolises based on images of land use and relevant socio-economic statistical data from 1990 to 2008. The research results indicate that: urban space grows rapidly especially after 2000 in general but shows a decelerating trend with a lowering rank in the population-size hierarchy; the growth trend of urban spatial elements inclines to be new and diverse; the growth of urban spatial structure shows a zonary and polycentric pattern; the growth of spatial morphology displays a pattern of decentralization and fragmentation; the urban spatial growth patterns are mainly axial and jumping oriented. Furthermore, we find that the major causes of urban spatial growth in Chinese metropolises are fast economic growth, rapid urbanization and GDP-oriented view of achievement in city government. Finally, the paper argues that the main problems of urban spatial growth in Chinese metropolises are excessive growth of the scale, scattered structure and fragmented morphology. Thus we suggest that the urban growth policy should focus on scale control, structure optimization and spatial compactness.