基于空间尺度变化的自贡城市热岛景观参数演变分析

Analysis on Evolution of Urban Heat Island Landscape Parameters in Zigong Based on Spatial Scale Variation

摘要: 近年来，随着城市化进程不断加快，土地利用和土地覆盖发生了较大变化，城市热环境也相应发生了较大的改变。以自贡市作为研究对象，利用2001~2013年等时间间隔5幅Landsat遥感影像进行地表温度反演、植被归一化指数反演；再对地表温度划分出不同的热岛等级；利用监督分类中的最大似然法对自贡市土地利用类型进行分类。在不同空间尺度基础上使用景观格局指数分析自贡城市热岛景观格局随城市化演变的趋势。结果表明：自贡市随着城市化进程的加快，地表温度也在不断攀升，城市热岛效应加强，整个热岛景观也变得更加破碎化；不同空间尺度下地表温度值并不相同，因此热岛范围的划分也不相同，导致在不同热岛等级下的城市景观格局参数也存在着差异。

Abstract: In recent years, along with the accelerating process of city, land use and land cover change greatly, city thermal environment has undergone great changes. Taking Zigong city as the research object, this paper uses five Landsat remote sensing images from 2001 to 2013 of equal time interval to achieve the LST and NDVI inversion, and the LST is divided into different types of heat island grades, then the maximum likelihood method of supervised classification is used to classify the land cover of Zigong city. Finally, the landscape pattern index is used to analyze the trend of urban heat island’s landscape pattern change with urbanization in Zigong city based on different spatial scales. The results show that with the acceleration of urbanization process, the LST of Zigong city is rising, urban heat island effect in strengthening, the entire island landscape become more fragmented, the LST is different under different spatial scales. Therefore, the division of the heat island range is not the same which leading to the differences in parameters of the urban landscape pattern in different heat island grades.