昆明市主城区热环境效应及影响因素分析

以昆明市主城区为研究对象，根据2000年、2010年和2020年3期Landsat TM/OLI遥感影像，反演3个时期的地表温度，采用标准差椭圆分析热环境效应的时空演变，并使用地理探测器探讨热环境效应的影响因素。结果表明：近20 年来，昆明市主城区热岛区集中分布在城镇建设密集区域，热环境方向主轴由东北—西南走向转为西北—东南走向；前期热环境重心向西北方向偏转了57.5°，偏移2.47 km，后期向西北方向偏转24.25°，偏移0.86 km；有极低温区向低温区、较低温区转变，较高温区与高温区向极高温区转变的态势，其中，官渡区的热环境效应增强趋势最显著；建筑用地和植被覆盖度对地表温度产生的影响力最大，建筑用地与高程交互作用时会增加对地表温度的影响力，水体与建筑用地或不透水面的交互作用减弱了水体对热环境效应的缓解作用。

Analysis of thermal environment effect and its influencing factors in the main urban area of Kunming

Taking the main urban area of Kunming as the research object, based on LandsatTM/OLI remote sensing images of three periods in 2000, 2010 and 2020, the surface temperatures in three periods were inversed. The temporal and spatial evolution of the thermal environment effect was analyzed with the standard deviation ellipse, and the influencing factors of thermal environment effect were discussed by the geographic detector. The results showed that in the recent 20 years, the heat island areas in the main urban area of Kunming had been concentrated in those with intensive urban construction, and the main axis of the thermal environment direction had changed from northeast-southwest to northwest-southeast. In the early stage, the center of the thermal environment deflected 57.5° to the northwest and shifted by 2.47 km, and in the later stage, deflected 24.25° to the northwest and shifted by 0.86 km. There was a trend of transition from extremely low-temperature zone to low-temperature zone and relatively low-temperature zone, and from relatively high-temperature zone and high-temperature zone to extremely high-temperature zone. Among them, the enhancement trend of the thermal environment effect in Guandu District was the most significant. The building lot and fractional vegetation cover (FVC) had the greatest influence on the surface temperature. The influence on the surface temperature would be increased when the interaction between building lot and elevation. And the interaction between water and building lot or impermeable surface would weaken the mitigation effect of water on the thermal environment effect.