南岭小坑木荷群落地上生物量

Aboveground Biomass of a Naturaly-regenerated Schima superba Community at Xiaokeng of the Nanling Mountain

森林生物量是评价森林生态系统生产力、研究森林生态系统结构与功能的重要指标,也是深入了解森林生态系统变化规律的重要途径和评估森林碳收支的重要参数（吴仲民等,1998）。亚热带常绿阔叶林是我国面积最大的森林类型。

Biomass of a naturallyregenerated 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 thm2. Biomass of the tree layer, understory layer, liana and litter layer were 114. 085, 1. 126, 0.38, 2. 881 t. hm2, 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 about0.4% for 〈5 cm, 16.8% for5 10 cm, 40.1% for1015 cm, 31.7% forl5 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.