Abstract:

Based on the data collected by located observation, the biomass and productivity of the second generation of Chinese fir plantation at fast growing stage was studied. At the same time, a comparison of biomass and productivity between the first generation and the second of successive rotation was made. The results showed that biomass of tree and stands in the first and second rotation Chinese fir plantation were 37.54, 34.74kg and 85.6,71.45 t·hm^-2, decreased by 8.52% and 16.53% respectively. The total biomass of the ecosystem in the first and second rotation account for 87.93 and 76.02 t·hm^-2, of which trees occupied a large portion. The biomass of shrub, herb and litter in the second rotation was 2 times of that in the first rotation. The first rotation Chinese fir had a stronger competition for underground and higher biomass accumulation in stem, while the second had stronger competition for above ground and lower biomass in stem. Productivity of the second rotation Chinese fir plantation was 6.49 t·hm^-2a^-1, and lower than that of the first rotation (7.78 t·hm^-2a^-1). However, the leaves in the second rotation had higher photosynthesis productivity. This case confirmed that there was potential improvement in productivity in the second rotation Chinese fir plantation.

Key words: Chinese fir plantation, Biomass, Productivity, Effect of successive-rotation, Fast growing stage