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机构地区:[1]甘肃省林业科学研究所
出 处:《甘肃林业科技》1997年第3期8-12,共5页Journal of Gansu Forestry Science and Technology
摘 要:营造株行距1×1m、1×2m、2.5×3m不同造林密度的白榆试验林,14年的试验结果表明,3种不同栽植密度对林分的高生长影响不大,但对胸径生长影响非常明显。2.5×3m密度的试验林比1×1m、1×2m密度的胸径生长大32.03%和52.48%;1×2m密度的比1×1m密度的胸径大15.49%。根据树冠与胸径生长的关系推算合理的栽植密度,兼顾用材等经济效益营造白榆成片林,培育8cm以上的小径材,初植密度每公顷不能大于5000株;培育16cm以上的中径材,初植密度每公顷不能大于1500株。On the basis of creating experimental stands of white elm for 14 years, with different afforestation densities of 1×1m, 1×2m, 2.5×3m, the results indicate that different afforestation densities have no remarkable affect on increment of height, but very much on diameter increment, the diameter increment of 2.5×3m′s experimental stands is 32.03% and 52.48% more then that of 1×1m and 1×2m′s respectively, and that of 1×2m′s is 15.49% more than that of 1×1m′s. The optimal afforestation density could be worked out according to the relation of canopy to diameter increment, with regarding to economic effect of wood. The initial stand density should be less than 5000 per hm 2 for ≥ 8cm undersized trees, and 1500 per hm 2 for ≤16cm intermidate trees.
分 类 号:S792.190.5[农业科学—林木遗传育种]
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