以芳香油和薪材为最终产品的桉树幼林地上部分生物量研究

Biomass Studies in Young Eucalypt Plantations for Oil and Fuelwood Production in Southwestern China

在2年生的桉树引种试验林内,对蓝桉和新引种的5种其他桉树的地上部分生物量进行了测定。研究发现,当轮伐期为2年时,不同桉树的芳香油和薪材收获量差异显著,而同一树种的芳香油和薪材产量在不同造林密度之间无显著差异。史密斯桉和贝克桉的芳香油和桉树脑含量均高于蓝桉,是生产桉树芳香油和薪材的优良树种,在我国亚热带地区有进一步试验和推广的价值。

The above-ground biomass of two components for 6 species of Eucalyptus, E. bakeri, E. smithii, E. radiata SSp. radiata, E. dives, E. macar-thurii and E. globulus ssp. globulus, was estimated two years after planting using samples taken from an experimental plantation which was designed as split-plots in 3 replicates in southwestern China. The plantation was established in three different spacings,0.5m×2m,1.0m×2m and 1.5m×2m. It was found from the preliminary results that there were significant differences in both growth rates and above-ground biomass between species. All species, except E. bakeri, gave the highest biomass production of both wood and leaves in fresh weight at the second spacing, 1.0m×2m. At this spacing E. smithii was ranked on the top reaching 4.5m in height and 5.2 cm in diameter and followed by E. globulus ssp. globulus in height of 4.1 m and ground-level diameter of 4.9cm, while E. bakeri was the last. Essential oil content of leaves was also analysed in the laboratory for each species. It was shown that all the six eucalypts could be managed in short rotation forestry for wood energy production which would bring about very good income to farmers in rural communities. E. smithii, which was for the first time grown in China, could become a better species than E. globulus ssp. globulus for oil and fuelwood production even the latter had become a land race in southwestern China.