Quantifying the Spatial Heterogeneity Relations Between Thermal Environment Effects and Influencing Factors Based on Geodetector in Central City of Chengdu

Abstract

To address the current situation that urban thermal environment research lacked comprehensive assessment and analysis from natural-social multidimensional factors, this study analyzed the evolution characteristics of thermal environment effects in the central urban area of Chengdu from 2004 to 2019 based on multi-source data. A total of seven influencing factors of natural and social factors that were highly associated with the urban thermal environment were selected, and the influencing factors of spatial differentiation of land surface temperature (LST) and their interactions were studied by applying Geodetector. The results showed that: (1) the heat island in the central city of Chengdu from 2004 to 2019 was radiating outward from the center, and the spatial development spine of the thermal environment remained in the "southeast-northwest" direction, with a significant shift of the center of gravity of the thermal environment from 2011 to 2019; (2) the average LST from 2004 to 2019 increased from 36.57℃to 40.64℃, and the total area of heat island area increased from 641 km² to 958 km². overall, it showed a shift from sub-medium zone and medium temperature zone to sub-high temperature zone and high temperature zone, and the urban heat island effect tended to enhance; (3) the nighttime light intensity had the largest amount of contribution to the spatial differentiation of LST, and social factors had a more important position relative to natural factors in influencing the urban thermal environment but the amount of contribution from natural factors kept increasing.