[Evolution Characteristics of Surface Urban Heat Island Intensity and Spatial Heterogeneity of Driving Factors in the Main Urban Area of Beijing].

The optimization and mitigation of urban heat island intensity is an important issue for cities to build a high-quality living environment and improve residents' comfort and happiness. To connect with the internal logic between the optimization of territorial space， the spatial evolution and driving factors of the heat island intensity in the main urban area of Beijing was measured from the four aspects of "overall pattern evolution， cross-transformation features， transformation modes， and driving factors" based on Landsat images of the main urban area of Beijing from 2005 to 2021， and the spatial heterogeneity of driving forces were analyzed. The results show that： ① From 2005 to 2021， the surface heat island intensity of the main urban area of Beijing presented a spatial pattern of decreasing from the center to the periphery， but the spatial aggregation of the high temperature area was gradually weakened， the high temperature range was obviously extended， and the northwest heat island intensity was significantly increased. ② The cross-conversion towards a "medium temperature area" was the main type of heat island intensity transformation in the main urban area of Beijing. By region， the cross-conversion towards a "medium temperature area" was the most intense in the outer urban area of the Fifth Ring Road， and the main conversion direction was the "medium temperature area" in the inner urban area of the Second Ring Road. ③ Building coverage， vegetation coverage， and water body index were the leading driving factors to optimize heat island intensity， and the leading factors of the intensification of heat island intensity were surface roughness， road density， and impervious surface ratio. From the perspective of spatial heterogeneity of driving factors， for the adjustment of the thermal environment of the block， the contribution degree of vegetation coverage and impervious surface ratio was more significant in "aggressive" streets， the driving force of building coverage was greater in "intensive" streets， and the regulation of road density was more critical in "balanced" streets. In the "adaptive" street， the contribution of water index and surface roughness was stronger. The above results can provide scientific reference for the study of local climate change of the urban surface heat island and the construction of a sustainable human settlement environment.