西南桦纯林与西南桦+肉桂混交林幼林期的生物量研究

A Study on Biomass in Sapling Stage of Pure Betula alnoides Forest and Betula alnoides and Cinnamomum cassia Mixed Forest

对在西双版纳普文林场营造的西南桦纯林(13年生),西南桦+肉桂混交林(15年生)两种幼林期西南桦人工林的生物量进行了研究。结果表明:幼林期,西南桦+肉桂混交林的总生物量为137.329 2 t/hm2,西南桦人工林的总生物量为84.979 2 t/hm2。两种林分幼林期生物量的层次分配比例以乔木层所占的比例最大,占66%以上;灌木层所占比例相差不大;因林分的群落结构不同,草本层及层间植物的生物量相差较大。生物量的器官分配比例以干材所占比例最大,都达到55%以上,其乔木层各器官生物量的分配比例顺序为:干材>根>枝>叶。两种西南桦人工林幼林期生物量的研究结果还表明,林分的总生物量由其群落结构、植被种类组成所决定,群落结构越复杂,其生物量越高。另还建立了西南桦林木各器官的生物量回归模型。

The biomass of 13 years old pure Betula alnoides forest and 15 years old Betula alnoides and Cinnamomum cassia mixed forest planted in Puwen forest farm of Xishuangbanna prefecture were studied. The experimental results showed that the biomass of pure Betula alnoides forest and Betula alnoides and Cinnamomum cassia mixed forest in sapling stage were 84. 979 2 t/hm^2 and 137. 329 2 t/hm^2 respectively. The tree layer had the highest percent of biomass, with was accounted for 66 % or above, the percent of shrub of these two stands was similar. The biomass of herb layer and inter-layer of two stands had big difference. The biomass of stem surpassed 55 %. The distribution of biomass in different organs decreased in the order of stem, root, branch and leaf. The experimental results also indicated that the total biomass of two kinds of Betula alnoides was decided by the population structure and vegetation composition. The biomass increases as the population structure becoming more complex. Besides, the biomass regressive model of different organs of Betula alnoides was established.