Abstract:

Biomass of a naturally-regenerated Schima superba community was measured using the harvest method in an 800 m² plot at Xiaokeng of the Nanling Mountain, Southern China, where 20 tree species were recorded and S. superba was the dominant tree species. Dry weight of stem, branch and leaf, and tree height (H) and diameter at breast height (DBH or D) were measured for all 210 trees with DBH above 3.0 centimeter in the plot. Aboveground biomass (AGB) of the forest community and its distribution among different layers, tree species and organs of the tree layer were estimated, respectively. Regression models of biomass were established based on these AGB data. The results showed that total aboveground biomass of the S. superba community amounted to 118.472 t·hm^-2. Biomass of the tree layer, understory layer, liana and litter layer were 114.085, 1.126, 0.38, 2.881 t·hm^-2, respectively. Tree stem, branch and leaf accounted for 78.2%, 13.1% and 8.7% of total biomass in the tree layer, respectively. Biomass of dominant tree species, S. superba, occupied about 33.3% of total biomass of the tree layer, suggesting that biomass of forest community in the early succession phase was mainly allocated to dominant tree species. The allocation of total aboveground biomass for each DBH class was about 0.4% for <5 cm, 16.8% for 5-10 cm, 40.1% for 10-15 cm, 31.7% for 15-20 cm, 5.8% for 20-25 cm, and 5.2% for >25 cm DBH classes, respectively. The distribution of biomass pattern among different DBH classes indicated that the forest community was in an early succession phase.

Key words: Schima superba community, aboveground biomass, biomass allocation, regression models, subtropical secondary forest, Nanling Mountain