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.

This paper deals with some ecophysiological characteristies of plant growth, parameters of physiology, material accumulation and community composition in apline bushland. The results are as follows:

1 Leaf area index and average rate of growth of some species of Gramineae, Cyperaceae m Dasiphora fruticosa alpine shrub are increased with decreaded grazing intensity. The height and coverage of the community were negatively correlated with grazing intensity (P<0.001).

2. Changes of the aralytical growth parameters: LAR, SLA, LWR and LAI were negatively correlated with grazing intensity. Leaf area index was positively correlated with biomass (P>0.005); Aboveground biomass was negatively correlated with grazing intensity (P<0.001).

3. The species numbers of Gramineae, Cyperaceae in Dasiphora fruticosa shrub community were decreased in heavily grazed area and increased in lightly grazed area. But the proportion of Forb was increased with heavy grazing and decreased with light grazing. Thus light grzaing in alpine scrub showed profitable for plant growth and regeneration.

In this paper, the litterfall productions, compositions. Seasonal distributions and nutrient element tumovers were compared on the seven forest types distributed on the east and the west vertical zones in Ailao Mountain.

The results are useful for recognizing litterfall element returns in the forests in Southwest monaoon area, subtropical montane forests manergement, rational exploitation and protection of soil source, and enhance of productivity.

The biomass and primary production of a natural Fargesia scabrida forest were determined based upon the regression models obtained by measuring the average basal diameter (D), density (N), plant height (H), and the dry weights of stems(Ws), branches(WB), leaves(WL) and rhizomes(WR) of Fargesia scabrida plants in the sampling quadrats. The regression models are as follows:

Ws=160.942+0.227(D2NH) p<0.001

WB=76.008+0.039(D2NH) p<0.001

WL＝80.643+0.051(D2NH) p<0.001

WR=285.554+0.074(D2NH) p<0.001

By using these models, we calculated that the biomasses of stems, branches, leaves and rhizomes were 7.558 t/ha., 1.782 t/ha., 2.143 t/ha. and 4.795 t/ha., respectively. The total biomass was 16.278 t/ha. The net primary production was estimated to be 3.256 t/ha./yr.