西双版纳热带次生林生物量的初步研究

 本文采用“空间代替时间”和维量分析的方法研究了西双版纳热带次生林4块不同年龄林分的生物量，并详细分析了热带次生林在演替初期阶段生物量的变化趋势。结果表明：林分总生物量随林龄而增加，5年生林分的总生物量为41.932t·hm-2，10年生林分的总生物量为52.116t·hm-2，14年生林分的总生物量为88.284t·hm-2，22年生林分的总生物量为113.743t·hm-2。林分生物量的层次分配比例以乔木层所占的比例最大，占4/5以上，随林龄而增加；灌木层增长到14年生林分后又下降，草本层随林龄而递减，层间植物则上升。生物量的器官分配比例以干材所占的比例最大，占1/2以上，随林龄而递增；而枝、根和叶的生物量分配比例则随林龄而下降。并建立了4个林分主要优势种及乔木层器官生物量的回归模型。

A PRELIMINARY STUDY ON THE BIOMASS OF SECONDARY TROPICAL FOREST IN XISHUANGBANNA

The methods in which different of space distribution stands for progress of time and the dimension analyses were used to study the biomass of four different secondary tropical forests in Xishuangbanna. The dynamic on the biomass of secondary tropical forests at the early stages of the secondary succession was analyzed in detail. The results show that the total biomass of four secondary tropical forests increased with the stand age. Total biomass in 5-year-stand, 10-year-stand, 14-year-stand and 22-year-stand were 41.932t· hm-2 , 52.116t·hm-2, 88.284t· hm-2 and 113.743t·hm-2 ,respectively.In the allocation of biomass in different layers in four stands, the biomass of tree layer was over 80% of the total. The biomass of shrub layer increased until 14-year old, then droped down, while the biomass of grass layers decreased and that of inter-layer increased with the stand age.Concerning different parts of plant in the four stands, the biomass of trunk, which occupies over 50% of the total, increased with the stand age, but those of branch, root and leaf decreased. The optimum regression models of different dominant plants and organs of the sample trees of tree layers in the four stands of secondary tropical forest were built.