Effects of Spatial Pattern of GreenSpace on Land Surface Temperature: A case study on Oasis City Aksu, northwest China

Abstract

The urban heat island (UHI) refers to the phenomenon of higher atmospheric and surface temperatures occurring in urban areas than in the surrounding rural areas. Numerous studies have shown that increased percent cover of greenspace (PLAND) can significantly decrease land surface temperatures (LST). Fewer studies, however, have investigated the effects of configuration of greenspace on LST. This thesis aims to fill this gap using oasis city Aksu, northwest China as a case study. PLAND along with two configuration metrics were used to measure the composition and configuration of greenspace. The metrics were calculated by moving window method based on a greenspace map derived from Landsat Thematic Mapper (TM) imagery, and LST data were retrieved from Landsat TM thermal band. Normalized mutual information measure was employed to investigate the relationship between LST and the spatial pattern of greenspace. The results showed that PLAND was the most important predictor of LST. Configuration of greenspace also significantly affected LST. In addition, the variance of LST was largely explained by both composition and configuration of greenspace. Results from this study can expand our understanding of the relationship between LST and vegetation, and provide insights for improving urban greenspace planning and management.