Abstract: Based on the mean DBH measurements of sample trees,the bioproductivity of subtropical Castanopsis hysrix-Cyclobalanopsis glauca Machilus pauhoi community in Huitong, Hunan province was studied by regression analysis (y=a(D²·H)^b). The results showed that the total biomass of the forest was 451.02 t·hm^-2, and the component biomass of tree, shrub, liana and litter layer was 426.76,17.76,1.80 and 4.70t·hm^-2, respectively. The net production and average production of tree layer were 34.46 and 13.32 t·hm^-2·yr^-1,respectively.

Key words: Community, Biomass, Net production, environmental factor, subtropical coniferous plantation, extreme high temperature, net ecosystem exchange of carbon dioxide, wavelet analysis.