基于遥感的城市温度与植被相关性分析——以四川省内江市为例

RS-based Analysis of the Correlation between Brightness Temperature and Vegetation Cover

以四川省内江市为研究区,以1988年6月23日、2007年5月6日Landsat TM数据和2000年5月10日的Landsat ETM+数据源,利用TM/ETM+热红外波段定量反演亮度温度,并计算归一化植被指数(NDVI)。在EXCEL软件中进行地表温度与NDVI之间的线性回归分析。结果表明:建成区大部分地区NDVI值较小,这是由于市区内有大量建筑、道路等硬化下垫面,植被覆盖少;部分植被覆盖较好的片区NDVI值较大;沱江水面NDVI值较小,为负值;除建成区和沱江以外的乡村区,植被覆盖良好,NDVI值较大。亮度温度与植被覆盖存在着明显的负相关,即植被覆盖越高的地方,温度相对较低,反之,温度则较高。

Landsat TM data （June 23,1988, May 6,2007 ） and Landsat ETM ＋ data （May 10,2000） of Neijiang City, Sichuan Province was taken as the data source, brightness temperature of the study area was obtained by using TM/ETM ＋ thermal infrared wave, and also normalized difference vegetation index （NDVI） was calculated. Linear regression analysis of the correlation between vegetation cover and NDVI was ear- lied out in Excel. The results showed that （a） most of the constructed area has a low NDVI value because there are large areas of hard surface such as buildings and roads,but less vegetation cover; （b） the quarters with better vegetation cover have higher NDVI values; the Tuojiang River has a negative NDVI value ; rural areas have better vegetation cover and higher NDVI values. Brightness temperature and vegetation cover has distinct negative correlation, specifically, the higher the vegetation cover is, the lower the surface temperature is, and vice versa.