THE RADIATION ABSORPTION EFFICIENCY OF PHOTOSYNTHESIS OF THE FOREST COMMUNITIES IN THE DINGHUSHAN MOUNTAIN
鼎湖山森林群落的光能利用效率

In this paper, the radiation absonption efficiency of the photosynthesis of the subtropical monsoonal broad-leaved evergreen forest (Castanopsis chinensis+Schima superba+Cryptocarya chinensis community) and the needle broad-leaved mixed forest (Pinus massoniana+Schima superba+Castanopsis chinensis+Craibiodendron kwangtungense community) in the Dinghushan mountain were described. The photosynthetic rates of 58 individuals of 22 main species at different layers of community were measured with an infrared CO_2 analyzer. The leaf area index of community were measured by the method of dripping tag, and the vertical distributions of the photosynthetically active radiation were measured by the level moving quantum sensor in two forests.The results showed that the radiation absonption efficiency of the photosynthesis a for the gross primary productivity was 14.28% and 12.01% in the monsoonal broad-leaved evergreen forest and the needle broad-leaved mixed forest, respectively. Therefore, the photosynthesis efficiency of the monsoonal broad-leaved evergreen forest is higher than that of the needle and broad-leaved mixed forest.