Abstract:

Biomass and its allocation of the subtropical evergreen broad-leaved forest in Heishiding Natural Reserve was studied based on the standard trees and regression analysis (for tree layer) and clear cut (for shrub and herbaceous layer).

1: Four regression models: (a) Y = a + bX, (b) Y = aXb, (c) Y = aebX, and (d) Y=a+blnX could be successfully applied to the forest, among which (b) and (c) had generally high r values. But for leaf biomass of the biggest standard tree group, model (a) was the only regression which was significant at acceptable confident fimit.

2. Biomass of the forest was 357.976t·ha-1, among which trunk 223.017 (62.30%), branch 45.834 (12.80%), leaf 15.609 (4.36%), and root (excluding D≤3mm fine roots) 73.517 (20.54%). Most of the biomass (353.520t·ha-1) was in the tree laver.

Vertical allocation of total biomass and trunk biomass showed a pyramid pattern, but that of branch biomass, demonstrated a reverse trend. Leaf biomass distributed dominantly above 15m, but below this height, there was still rather important leaf biomass, reflecting the structural complexity of the forest. LAI was 17.1. Allocation among different diameter classes presented a normal distribution.

3. Aboveground and total biomasses were 1.27 and 1.60 times that of trunk respectively. Analysis on other tropical and subtropical forests provided similar results.