A Research on the Spatial Structure and Efficiency of China's Expansion of Urban Built-up Area(1990-2009)
基于1990-2009年中国260个城市数据，分析城市扩张的阶段特征、空间结构及效率，发现扩张与人口增长不匹配，建议不同城市选择合适发展路径。
We select the data of China's 260 cities from 1990 to 2009;analyze the characteristics,the spatial structure and evolution of urban expansion based on rank-size law,the index of and GIS.Then we introduce an index of to evaluate the efficiency of urban expansion.The research results are as follows:(1) Urban expansion has obvious stage characteristics,mainly due to the adjustment of national urban strategy.Urban development trend after 2000 is not balanced and urban system has turbulent changes.(2) The trend that urban built-up areas are getting larger is more significant.Urban type is promoted to a higher level.City regional spatial distribution is extremely uneven.The regional differences of the city situated lead to urban sprawl,thus the city status also changes.(3) The urban growth rate of all regions was significantly different.The provincial capital city expansion is slow at first but fast at last.The urban expansion of many cities formed a regional group.Urban rapid expansion mismatches with the urban population growth.The overall urban rapid expansion should be slowed down.(4) The efficiency of urban expansion is very different at different stages.The level of expansion efficiency pointed out that the urban built-up expansion in different city should choose appropriate development path,and develop appropriate policies and measures.