基于不透水地表比例的城市扩展研究

不透水地表比例是衡量城市化水平的一个重要指标，采用不透水地表比例可以研究城市的空间变化和扩展并定量化城市空间变化和扩展的强度。使用多端元光谱混合分析方法可以从TM影像中提取亚像元尺度的不透水地表比例，用该方法从两个时相的TM影像中提取南京都市发展区不透水地表比例，在此基础上定性和定量地分析该区域的空间变化和扩展。

Urban Sprawl Study Based on Impervious Surface Percent

Impervious surface percent is an important index to indicate urbanization level; it can be used to study the change and spatial extension of urban area quantitatively.Multiple endmember spectral mixture analysis method was used to extract sub-pixel level of impervious surface percent from TM image.This paper applies that method to extract the impervious surface percent of Nanjing Metropolitan development area from two temporal TM images.Then based on impervious surface percent,the change and spatial sprawl of study area was analyzed qualitatively and quantitatively.