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出 处:《林业科学》1993年第5期472-476,共5页Scientia Silvae Sinicae
摘 要:油松是山西太行山区的主要造林树种,现有人工林16.2万ha,由于造林密度不够合理,不少地方成林不成材。确定适宜造林密度的标准和方法是较多的,从太行山区群众生产生活中需求一定数量小径材的实际情况出发,我们认为林分第一次间伐时,大部分间伐木能达到小径材(椽材)标准的密度,是较为适宜的密度,可获得较好的造林经济效益,“七五”期间,我们对太行山西侧的油松人工林密度进行了调查总结。According to the information of 337 sample plots of 20-25-year-oldChinese pine plantation at sapling stage, the diameters at breast height offorest trees which are at the standard of 4m or 2m rafter timber, have beendetermined in this paper. The regression equations of density and numbers ofsapling timber have also been established based on the site types, and thenumbers of 4m and 2m sapling timbers in different density stands have beenanalysed. The number of 4m sapling timber per unit area is positively corre-lated with the volume and economic value of sapling timber. The stand den-sity and planting density have been proposed for the goal of sapling timberin Chinese pine plantation.
分 类 号:S791.254[农业科学—林木遗传育种]
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