结合地理探测器的长沙市区地表温度驱动力探究

Study on the Driving Force of Land Surface Temperature in Changsha Urban Area in Combination with the Geographic Detector

为了感知城市地表温度空间分布格局及异质性特征,本文从不同视角解读地表温度的驱动因素及其相互作用,并以长沙市区为研究区域,利用单通道算法反演地表温度,提取归一化植被指数(NDVI)、改进的归一化水体指数(MNDWI)和归一化建筑指数(NDBI),将其与夜间灯光、POI数量、道路密度、坡度、海拔等影响因子结合,采用地理探测器分析长沙市区地表温度驱动因素。结果表明:长沙市区地表温度整体呈现“中间高,四周低”的不规则环形空间分布格局。夜间灯光对地表温度的影响程度最大,是地表温度升高的主要驱动因素。交互探测器结果显示,双因子交互作用整体表现为增强,而夜间灯光与MNDWI交互作用对地表温度的解释力最大。

In order to perceive the spatial distribution pattern and heterogeneity of urban ground surface temperature, and interpret the driving factors of landsurface temperature and their interactions from different perspectives, this paper takes Changsha urban area as the research area, and uses the single-channel algorithm to retrieve landsurface temperature. Normalized Vegetation Index(NDVI), Improved Normalized Water Index(MNDWI) and Normalized Building Index(NDBI) were extracted and combined with influencing factors such as nighttime light, POI number, road density, slope and elevation, etc. The driving factors of landsurface temperature in Changsha urban area were analyzed by geographic detector. The results show that the overall surface temperature in Changsha presents an irregular circular spatial distribution pattern of "high in the center and low in the surroundings". Nighttime light has the greatest influence on LST and is the main driving factor. The results of the interaction detector show that the two-factor interaction is enhanced overall, and the interaction between night light and MNDWI has the greatest explanatory power for LST.