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

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.