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在桂中象州县，采用随机区组试验设计研究不同造林密度（８３３ 、１１１１ 、１２５０ 、１４２９ 、１６６６ 、２０００ 、２５００ 株／ｈｍ２） 对６ａ 生尾叶桉（ Ｅｕｃａｌｙｐｔｕｓ ｕｒｏｐｈｙｌｌａ） 生长、产量及木材材性的影响。经过一个轮伐期的定位观测，探讨种群密度与胸径、树高、立木单株材积、林分蓄积量、木材气干密度、木材纤维形态、冠幅、枝下高、林分保存率等的作用规律和相关模型。结果表明：密度对胸径、立木单株材积、冠幅及枝下高的影响达极显著水平；对蓄积量、木材纤维宽度、导管分子长度的影响达显著水平；对树高、木材气干密度、木纤维长度虽有一定的影响，但不显著。根据试验结果提出尾叶桉人工林的合理密度范围在１２５０ ～２５００ 株／ｈｍ２ 之间，短周期工业用材林的最佳密度为２０００ 株／ｈｍ２ ，主伐年龄为５ ～７ａ 。
In Xiangzhong County of Guangxi Zhuang Autonomous Region, a randomized block experiment was conducted to study the effects of different planting densities (833, 1111, 1250, 1429, 1666, 2000 and 2500 plants per hectare) on the growth, yield and wood quality of Eucalyptus urophylla Material effects. After a rotation observation, the effects of population density and DBH, tree height, stand volume per plant, stand volume, air-dry density, wood fiber morphology, crown width, shoot height, Law of action and related models. The results showed that density had a significant effect on DBH, stand volume per plant, crown width and branch height, and significant effect on stock volume, wood fiber width and tube molecular length. Although the length of wood fiber has certain influence, it is not significant. Based on the results of the experiment, the reasonable density of Eucalyptus urophylla plantation ranged from 1250 to 2500 plants / hm2, the shortest-period industrial timber forest had the best density of 2000 plants / hm2, and the main cutting age was from 5 to 7a.