两种杨树矮林地上生物量及树皮比例早期测算

Biomass and Bark Content Estimation of Two Poplar Clones in Short Rotation Coppice

通过建立茎干离地22 cm的直径(D22)与单枝地上生物量的关系,估算林分地上生物量,并对三倍体毛白杨B301和欧美杨107在3种栽植密度下林分地上生物量及收获物质量进行早期测算。结果表明:三倍体毛白杨B301林分各栽植密度的单枝地上生物量和单枝树皮地上生物量差异均不显著;欧美杨107在20 000株/hm2栽植密度下,单枝地上生物量和单枝树皮地上生物量均显著小于栽植密度为5 000株/hm2;2种杨树林分地上生物量和林分树皮地上生物量均随着栽植密度的增大而增大,且各栽植密度间的差异达到了极显著水平。

In order to estimate the quality of biomass before harvesting, an a11ometric regression of bark percentage of total aboveground biomass and D22（ diameter at 22 em height） was developed in two poplar short-rotation coppice systems. There was no significant difference in shoot biomass and bark biomass of triploid Populus tomentosa B301 （（ P. tomentosa×P. bolleana） ×P. tornentosa） plantation, however, the shoot biomass and bark biomass of Populus×euramericana cv. ＇74/76＇ plantation in the density of 5 000 plants/hm^2 were significantly higher than those in 20 000 plants/hm^2. Both triploid Populus tomentosa B301 and Populus×euramericana cv. ＇74/76＇ showed significant difference in biomass and bark content between different densities.