爬山虎与五叶地锦对墙体降温效果差异及生理机制

Cooling Effect and Physiological Mechanism of Parthenocissus tricuspidata and Parthenocissus quinquefolia Planch.

为了研究不同攀缘植物对其所攀附的墙体的降温效果差异及其生理机制,以葡萄科爬山虎属的2种藤本植物爬山虎和五叶地锦为材料,利用Optris Minisight非接触红外测温仪测定植物冠层表面温度、冠下墙体表面温度和相应裸露墙体表面温度。用LI-1600稳态气孔计测定蒸腾、相对湿度、叶面温度、叶室温度、入射光照强度、反射光强和透射光强。采用OS-30p调制荧光仪测定叶绿素荧光参数Fo,Fm,并计算Fv/Fm。结果表明,爬山虎和五叶地锦对应裸墙温度日变化曲线均为倒"V"字型,最高可达(41.0±0.08)℃和(42.5±0.07)℃,日均降温(2.7±0.49)℃和(5.1±0.55)℃,最高降温达到(8.2±0.58)℃和(11.0±0.28)℃。五叶地锦的蒸腾速率是爬山虎的8.3倍,达到(9.1±2.0)μg.s-1.cm-2,并使照射到墙体上的光能减少了5.6%,而且叶绿荧光参数Fv/Fm为0.80±0.01,高于爬山虎的0.75±0.00。爬山虎Fo和Fm分别为73.4±0.98和295.2±2.96,而五叶地锦的分别为63.6±1.17和315.8±13.7。因此,五叶地锦较爬山虎的降温效果好,这种差异是蒸腾、光反射与透射和叶片光化学作用的共同结果。

Parthenocissus tricuspidata and Parthenocissus quinquefolia Planch. are used as vertical greening plants to cover the building envelope widely. They can mitigate ambient temperature. In order to determine the deviation between the cooling effects of them, non-contact infrared temperature thermometer （Optris Minisight） , Li-1600 steady state porometer and hand-held OS-30p chlorophyll fluorometer were employed to examine the temperature of bear wall, plant-covered wall, canopy, leaf and ambient air, transpiration and stomatal resistance, leaf albedo and transmission, basic chlorophyll fluorescence Fo, Fm and Fv/Fm. The result showed that there were inverted V-shaped curves for both bare facade corresponding two plants. The maximum bare wall temperature were （41.0±0.08） ℃ and （42.5±0.07）℃, mean day cooling values were （2.7±0.49）℃ and （5.±0.55）℃, maximum cooling values were （8.2±0.58）℃ and （11.0±0.28）℃ for P. Tricuspidata and P. quinquefolia Planch. , respectively. Transpiration of P. quinquefolia was （9.1±2.0） μg·s^-1 · cm^-2 which was 8.3 times of P. Tricuspidata. The reduction percentage of solar light which irradiated on plant-covered wall was 5.6%. Fv/Fm was 0.80±0.01 higher than 0.75±0.00 for P. Tricuspidata. Fo and Fm were 63.6±1.17and315.8±13.7, 63.6±1.17and315.8±13.7 for P. Tricuspidata and P. quinquefol Planch. , respectively. It can be concluded from above results that the cooling effects of was high that as an integrate actions of transpiration, leaf albedo, transmission and photochemistry.