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以胶合板材为培育目标，研究了Ｉ－６９杨胶合板用材林平均单株材积与造林密度和优势高的关系。分别不同林龄（６～１１ａ）建立了平均单株材积与造林密度及优势高的模型Ｖ＝ａ０Ｎａ１Ｈａ２０，通过生产弹性分析、边际产量分析，研究了密度效应及优势高效应，计算出了不同林龄林分的生产弹性值和边际产量，并且根据立地及密度效应模型研究了造林密度、林龄、立地指数对林分蓄积的影响。认为在长江中、下游地区营造Ｉ－６９杨胶合板用材林密度应适当减小，选择造林地时以立地指数大于等于２０ｍ林地为佳。
Plywood as a breeding goal, I-69 Yang plywood timber plantation average individual plantation density and superiority of the relationship. Based on the analysis of production elasticity and marginal yield, a model V = a0Na1Ha20 with average plant volume, plantation density and superiority was set up under different stand ages (6 ~ 11a) to study the effects of density and superiority and high efficiency. The production elastic value and marginal yield of stand, and studied the effects of plantation density, stand age and site index on stand volume accumulation according to site and density effect model. It is considered that the density of I-69 Yang plywood timber should be properly reduced in the middle and lower reaches of the Yangtze River. When the afforestation site is selected, the woodland with the site index greater than or equal to 20m is preferable.