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机构地区:[1]新疆农业大学林学分院,北京林业大学森林资源与环境学院
出 处:《北京林业大学学报》1996年第3期21-30,共10页Journal of Beijing Forestry University
摘 要:以天山云杉为研究对象,在分析与描述天山云杉干形的基础上,提出了新的削度模型;并与其它削度模型进行分析、比较,评价了与商品材积估测有关的削度模型的优劣,结果表明:新建削度模型具有较好地满足各项预估目的的能力,在此削度模型的基础上,建立了精确的商品材积估测系统。该系统可估计树干上任意直径的干长、任意高度处直径、商品材积,并用该系统编制了天山云杉二元材种出材率表。Take Picea schrenkiana var. tianshanica as an object of study,the thesis put for-ward some new taper functions on the basis of describing and analysing the stem profiles of thespecies.The new taper function was compared with other relative taper medels for merchantablevolume estimation. Results showed that the newly built taper function could better meet the vari-ous estimation needs. According to the new taper function,a precise merchantable volume esti-mation system was also established.It is now possible to estimate the length in the light of anydiameter of the stem,or to estimate the diameter according to any height on the tree,and corre-sponding merchantable volume and total volume of the tree by the system. With the system,two-way merchantable volume yielding rate tables for Picea schrenkiana var.tianshanica was lastlyconstructed.
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