尾叶桉U6无性系林分密度效应研究

Density Effects of Eucalyptus urophylla U6 Clone Plantations

文章分析了造林密度对 6年生尾叶桉U6无性系林分各生长因子的影响 ,结果表明 :造林密度对桉树人工林各林分生长因子的影响显著性不同 ,密度与胸径、单株材积生长呈显著负相关关系 ,6年生U 6无性系人工林平均胸径及平均单株材积生长量以密度D (16 6 5株 /hm2 ) >C(2 2 5 0株 /hm2 ) >B(2 812株 /hm2 ) >A(3333株 /hm2 )。密度对树高、林分蓄积量的生长均有一定影响 ,但差异不显著 ,林分平均树高生长量随着密度的增加而递减 ,林分蓄积量则以C处理最大 ,达 15 3.92 14m3/hm2 ;适宜造林密度范围在 15 36～ 2 4 81株 /hm2 之间。

The relationship between planting density and growth of 6-year-old plantations of Eucalyptus urophylla U6 clone were studied. Th e results showed that the effects of stand density on growth performance of the Eucalyptus plantations were quite remarkable. Density was negatively related to DBH and volume, the mean DBH and volume per tree of 6-year-old plantation s is treatment D (1 665 tree/hm2)>C(2 250 tree/hm2)>B(2 812 tree/hm2)>A ( 3 333 tree/hm2); Density had no significant effects on tree height and growing stock, the increment of tree height decreased with the increasement of density, and the growing stock reached 153.9214 m3/hm2 at treatment C (2 250 tree/hm 2 ); the appropriate planting density ranges from 1 536 to 2 481 tree/hm 2.