摘要
基于Landsat TM遥感影像反演地表温度,获取下垫面覆盖信息;选取了兰州市的商业区、学校、生活区和公园4种典型小区,研究不同类型小区地表温度热场与下垫面结构的关系。结果表明,水体、绿地具有明显的降温功能,建筑地面则增温效果明显,这3种地表所占的面积比例与小区平均地表温度关系密切。在所选取的绿地结构指数中,对温度影响从大到小依次为绿地覆盖率、分离度、斑块平均面积、连通指数、形状指数和分维数,其中,分离度与温度呈现正相关,其他指数与温度呈负相关。在所有类型小区中,温度从高到低依次为商业区、学校、生活区和公园。公园的温度分布在所有类型小区中最分散,商业区最集中。
The present paper is oriented to explore the thermal envi- ronment and vegetation coverage, the two key factors for urban eeo- environment. Taking Lanzhou, the capital of Gansu Province as a case, and by using the remote sensing data, we have retrieved the land surface temperature （LST）via mono-window algorithm. Then, we have chosen 20 blocks of the city, including commercial districts, school areas, residential quarters and park zones in the city to extract the land surface temperatures form both Landsat/TM images gained on August 26,1993 and August 6,2010, by using the geographic da- ta-retrieval system and a remote sensing software. Land-cover types we have gained from the interpretation of remote sensing images, and the pattern of ecological green space we have worked out has been e- valuated with a landscape software. And, last of all, we have ex- plored the relationship between the ground surface temperatures of various blocks and the underlying ground structures. The results of our investigation show that water area surface and the green space play a significant cooling role, while the building ground surface also produce very noticeable warming effects. All the above three kinds of surface area and the average LST of the explored blocks are closely related with each other. The effects of the following selected ecologi- cal green space indexes on the LST can be arranged in a declining or- der： the green space coverage, the separation space, average area of patch, cohesion index, shape index, and fractional dimensions. In ad- dition, a positive correlation can be found between the fractional di- mensions and LST, whereas a negative correlation proves to be existing between LST and other index. Of all the kinds of the selected blocks, a descending order of their LST can be detected from the commercial districts through school areas and residential quarters to the park zones. Whereas the I_ST distributions of the park zones are extremely sparse, those of commercial districts are most thickly condensed. Re- moval of rural land cover types, such as soil, water, and vegetation and their replacement with common urban materials, such as asphalt, concrete, and metal or glass have significant environmental implica- tions, including reduction in evapo-transpiration, promotion of more rapid surface runoff, increased storage and transfer of the sensible thermos and depletion of air and water quality, which have to account for the emergence of the urban heat islands in the city.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2012年第6期140-145,共6页
Journal of Safety and Environment
基金
国家自然科学基金项目(41061017)
甘肃省研究生导师科研项目(2012-14)
甘肃省建设科技项目(JK2012-25)
关键词
环境科学技术其他学科
热环境效应
地表温度
遥感
兰州市
other disciplines of environmental science and technolo- gy
thermal environmental effects
land surface temper- ature
remote sensing
Lanzhou
