合肥市城市热环境的空间变化及其驱动力分析

合肥市在进入21世纪后城市扩张十分迅速,城市热环境也随之发生改变.本文借助RS和GIS相关软件的支持,利用TM影像反演出地表温度并将其归一化处理.通过对比1995年9月18日和2007年10月5日的地表温度分布图和统计表发现在12年中研究区的热岛区域面积由68907600m2减少到66896100m2,减少了2011500m2;合肥市的热岛集中区由1995年的东部向2007年的西南部转移;老城区保护较好,在离合肥老城区中心0-2km的环形缓冲区内,低温、较低温、次中温和特高温的面积比例变化很小,高温区的面积减少,基本转变成中温区和次高温区;在2-5km的环形缓冲区内,各等级温度区变化较大;在5-13km的缓冲区范围内,较低温区和次中温区的面积一直在减小,低温区、次高温区和高温区的面积在增加.

Analysis of Space Change and Its Driving Force of Urban Thermal Environment of Hefei

In the 21st century,with rapid urban expansion,urban thermal environment of Hefei has changed.This paper uses TM image data to retrieve land surface temperature(LST) and normalization LST with the surpport of GIS and RS.By comparing two periods of LST images(1995 and 2007) and investigating statistical tables,the result shows that the area of urban heat island have reduced 2011500m2,from 68907600m2 to 66896100m2;urban heat island mainly occurred in the east of Hefei in 1995 and in the southwest of Hefei in 2007;within the ring buffer from old town centre of Hefei 0-2km,acreage of different classes area of temperature barely change for well protection of old town;in the ring buffer away from old town centre 2-5km,acreage of different classes area of temperature change significantly;in the ring buffer away from old town centre 5-13km,acreage of relatively low temperature zone and sub-middle temperature zone have been reduced,acreage of low temperature zone,sub-high temperaturezone and high temperature zone have been increased.