THE VERTICAL PROFILES OF CARBON, NITROGEN AND WATER CONDITION IN SCHIMA SUPERBA-CRYPTOCARYA CHINENSIS COMMUNITY OF SUBTROPICAL MOSOONAL FOREST

In Schima superba-Cryptocarya chinensis Community, greater weight per leaf(one side)and more number of stomata were found in tree layer comparied with that of understories. For most plants in this community, their leaf nitrogen is 12—20 Nmg/g DW, leaf phosprous is 0.4—1.0 Pmg/g DW. As the hight increases in vertical profile, nitrogen and phosprous content increase. Chlorophyll content and photosynthetic rate incease as the hight above forest floor increases. The results might show that more investments of carbon and nitrogen in leaves of tree layer were made for increasing photosynthetic income.Leaf water potential decreases during 7 a. m.—11 a.m., it drops to the lowest point at 15 p. m. The leaf water potential in leaves of tree layer is lower than that of understories. But leaves of tree layer have higher leaf cond-uctance.