城市热岛效应与植被覆盖度定量关系特征研究

Research on the Quantitative Relationship between Urban Heat Islands and Vegetation Fraction

以吉林省长春市为研究区域,以Landsat TM影像为基础数据,定量反演亮度温度代替城市气温表示城市热力场分布状况,提取了归一化植被指数,计算植被覆盖度,并利用RS和GIS技术在长春市东西和南北方向建立多个特征剖面,探讨了亮度温度与植被覆盖度的关联关系及其在空间上的分布规律。通过实测气温对亮度温度数据验证表明,亮度温度可以代表一个城市的热力场分布状况;通过一元线性回归得出,亮度温度与植被覆盖程度之间存在明显的负相关关系,且可用定量公式y=-4.743 3 x+299.95表示,相关系数为0.71。

This paper used the Landsat TM image of Changchun City, to invert the brightness temperature, which instead of urban air temperature to indicate city thermal distribution, to extract NDVI, to calculate the vegetation fraction, and used RS and GIS technology to create a number of characteristic profiles in Changchun City through east-west and north–south directions. It made a discussion on the relationship between brightness temperature and vegetation fraction and their spatial distribution regular pattern. The comparison between measurement of temperature and brightness temperature made it clear that brightness temperature might represent the thermal field distribution in a city. The study finds out that brightness temperature and vegetation have obvious negative correlation through Linear regression. And it can use y=-4.743 3x+299.95 to indicate, relative coefficient is 0.71.