Ecophysiological studies of alpine vegetation

Jeng-Hsien Weng and Tian-Syh Liao

Professor and Instructor, Depatment of Botany and Forestry, National

Chung-Hsing University, Taichung, Taiwan, ROC

Abstract

In order to understand the mechanisms of environmental adaptation of alpine plants, the ecophysiological characteristics include the stomatal aperture, gases exchange and water relation of early and late successional alpine plants were studied. It was found that stomatal resistance was varied with species and seasons; among them, the stomatal aperture of Rhododendron rubropilosum was insensitive to light intensity, and that of Yushania niitakayamensis showed midday depression. The stomatal openning were higher in summer, lower in winter; in addition, the variation of stomatal aperture in different seasons and species affected the temperature of leaves. Besides, high mountain original Miscanthus spp. and Tsuga chinensis showed less adapted to high temperature, whereas Alnus formosana showed wide temperature range adaptation in photosynthesis. Leaf water potential of alpine plants showed lower than lowland plants, and those showed low values in winter, high in summer. The results indicated that ecophysiological characteristics of alpine plants were closely associated with the thermal environments