Study on Biomass and Energy Use Efficiency of the Stands of Cunninghamia lanceolata in China

A comprehensive study on the energy use efficiency,pattern of energy balance and the productivity of Cunninghamia lanceolata was conducted.Different photosynthetic characteristics in the stands with different ages,densities and site qualities were shown,and the pattern of energy distribution,use efficiency and productivity are different in different regions,evaluation and stages of the tree growth.The present energy use efficiency for the total solar radiation income and photosynthetic active radiation is 0.38% and 0.81% respectively,and generally speaking,the value in the middle region is higher than that in the south,and that in the south is higher than that in the north region of the distribution areas of C.lanceolata. The net photosynthetic production of the leaf,the biomass and the growing stock is of the same feature,which is in direct proportion with the leaf are a index.A great potential is waiting for more rational cultivation.