20世纪90年代中国城市用地外延扩展特征分析

Characteristics Analysis of Urban Land Expansion in China in 1990s Using DMSP/OLS Data

以1992、1996和1998年三期夜间灯光图像为基础数据,辅之以交通图件,通过构建城市用地外延扩展强度指数,利用buffer分析、回归分析、梯度分析等,对比分析了城市用地外延扩展强度指数在不同规模的城市附近和不同类型的交通线路沿线的变化规律,探讨了城市规模和交通条件对城市用地外延扩展的影响,揭示了20世纪90年代我国城市用地外延扩展的一些基本特征。

Based on roads, highways and urban land expan n land expansion was d ent types of traffic lin the DMSP/OLS night light images in 1992, 1996 and 1998, the map of traffic lines including shown as follows ： （ 1 ） The expansion around cities decreased with distance according to the power function, while the expansion along traffic lines decreased linearly. （2） The expanding intensities around cities were apparently higher than those along traffic lines. （3） The decreasing grad in the buffers of traffic lines was less than that in the buffers of cities so far, and the decreasing grads in the near buffers was less than that in the far buffers for all kinds of traffic lines and the cities of medium and small scales. （4） Comparing with the values of 1992 - 1996, the expanding intensities of 1996 - 1998 showed an increasing trend and the increase around cities was changeable with distance, while the increase along traffic lines was unchangeable with distance.