西安城市热环境格局的动态演变

Dynamic changes of urban heat environment pattern in Xi'an of Northwest China

以TM和ETM+热红外数据为基础,采用单窗算法,研究了西安1995—2006年间热岛效应景观分布及其动态变化特征。研究表明:西安城市热岛效应明显,热场空间分布格局与城市的建成区基本一致;随着城市化进程的加快,西安市热环境格局表现出异质性加剧的趋势;东西和南北方向上,温度剖面线与土地利用与覆被关系密切,以建设用地地表温度最高、水域最小,其大小关系依次为建设用地>未利用地>耕地>草地>林地>水域。相关性分析表明,地表温度与归一化裸露指数(NDBI)呈正相关,与归一化植被指数(NDVI)呈负相关。

Based on the thermal band data of TM/ETM~ and by using mono-window algorithm, this paper studied the distribution pattern and dynamic characteristics of heat island landscape in Xi＇an from 1995 to 2006. In the study period, there was an obvious urban heat island effect in Xi＇an, and the thermal field spatial distribution pattern was identical with the built-up areas in the City. With the urbanization process of Xi＇ an, its thermal environment pattern presented a trend of increasing heterogeneity. In the east-west and north-south directions through the center of Xi＇an, the temperature profile had a close relationship with the land use/land cover. Construc- tion land surface had the highest temperature, while water area had the lowest one. The relation- ship between the land surface temperature and the land use/land cover was in the order of con- struction land 〉 unused land 〉 cropland 〉 grassland 〉 woodland 〉 water area. The surface tem- perature showed a positive correlation with the NDBI index, and a negative correlation with the NDVI index.