密度对大叶相思林生物量分配的影响

以密度为10 000、4 444和1 667株/hm2的4年生大叶相思林为研究对象,对各种不同密度林分中大叶相思各器官生物量分配、生物量径级结构和群落生物量进行了研究。结果表明:各密度大叶相思干的生物量占林分生物量的55%以上,根占14.11%~15.50%,叶占8.34%~10.76%,而在枝和皮的分配比例上差异较大;三种密度大叶相思林的总生物量径阶分配呈正态分布;群落总生物量随林分密度的增加而增加,但林下植物生物量随林分密度的增加而减小。

Effect of density on biomass allocation of Acacia auriculaeformis stands

The allocation pattern of organ biomass,radial structure and community of biomass were studied in four﹣yearold Acacia auriculaeformis stands with three densities (10 000,4 444 and 1 667 seedlings per hm2 ). The stem biomass of A. auriculaeformis stands accounted for above 55%of stand biomass,roots and leaves accounted for 14. 1 1%~15. 50%and 8. 34%~10. 76% respectively,whereas there were a great difference in distribution ratio for breach and bark bio﹣masses among the different density stands. The total biomass of diameter class in the A. auriculaeformis stands with three different densities exhibited the normal probability distribution. The total biomass of the community increased and the bio﹣mass of undergrowth decreased with increasing density.