Abstract
The responses of stamatal conductance to environmental factors, such as solar radiation, on Cryptomeria Japonic a in Japan and grasses in Tibetan Plateau were examined. Also, mechanism of water storage in trees with three types of xylem structures ; namely, C. japonica (coniferous wood), Magnolia salicifolia (diffuse-porous wood), and Quercus serrata (ring-porous wood) were investigated experimentally. The effects of environment factors on stomatai conductance varied with its location. The stomatai conductance in C. Japonica forest were heavily depend on solar radiation and water vapor pressure difference between atmosphere and the leaf. In the grassland on the Tibetan Plateau, the reaction to the water vapor pressure difference was significant. The response of water uptake to transpiration differed with the relations between water storage and water potential due to pore structures.
