地表温度直接影响着城市地表热场的分布和地表气温的高低,从而影响城市小气候环境。在太阳辐射条件下,利用红外测温仪连续观测桂林市不同绿化植被种类、水泥地、干燥裸土的表面温度,研究不同植被种类由于蒸腾作用不同所造成的表面温度差异,为城市绿化降低城市地表热场的热效应而合理选择植被种类。结果表明,樟树、紫荆等叶片的面积较大或者叶片表面的角质层较少,蒸腾作用较强,其表面温度日最高值低于裸土、水泥地分别约6℃、14℃,降温效果较显著;次之桂花、银杏和竹子的表面温度日最高值低于裸土、水泥地分别约4℃、12℃;棕榈、草地的蒸腾作用相对较弱,其表面温度日最高值低于裸土、水泥地分别约2℃、10℃,降温效果较差。 The surface temperature directly affects the distribution of urban surface thermal field and the surface air temperature, thus affecting the urban microclimate environment. Under the condition of solar radiation, the surface temperature of different green vegetation types, cement and bare soil in Guilin City was continuously observed by infrared thermometer to study the difference of surface temperature caused by different types of vegetation due to different transpiration, The thermal effects of the surface thermal field and the reasonable choice of vegetation types. The results showed that the leaves of camphor tree and Bauhinia were larger in area or had less stratum corneum on the leaf surface with stronger transpiration than the bare soil at the surface temperature of about 6 ℃ and 14 ℃ The highest daily surface temperature of Osmanthus fragrans, Gingko biloba and bamboo was lower than that of bare soil and cement at about 4 ℃ and 12 ℃ respectively. The transpiration of palm and grassland was relatively weak, and the highest daily surface temperature was lower than that of bare soil , Respectively, about 2 ℃, 10 ℃, cooling effect is poor.