Response of land cover types to land surface temperature derived from Landsat-5 TM in Nanjing Metropolitan Region, China

Nanjing (China) has undergone rapid urbanization since the reform and opening up in 1978. The urban heat environment has been affected significantly by human activities. In this paper, we aim at revealing the influence of land cover types on urban heat retrieved from the thermal infrared band of Landsat-5 Thematic Mapper. The results show that the high-temperature area is mainly located in the urban area of Nanjing, while the low-temperature area is located in the forest and water body areas. The average land surface temperature of Qinhuai District is the highest (29.1 degrees C), while Pukou District has lower temperatures. Geometrically, the city center has the highest temperature, and the land surface temperature gradually decreases with distance from the city center. The land surface temperature of industrial land is the highest, while rivers reveal the lowest temperature in the region (24.3 degrees C). The size and number of land cover patches have a positive correlation with the heat contribution. The construction land has the significantly positive correlation with land surface temperature, while arable land, forest, water body and wetland have significantly negative correlations. Land surface temperatures in highly growing urban areas are higher than the associated old town, and this is due to the use of new construction materials, and to lower vegetation coverage.