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    经营的马尾松森林类型发育演替阶段量化指标研究

    Quantitative indices to identify succession stages of managed Pinus massoniana forest

    • 摘要: 经营条件下的森林发育是自然演替和人为干扰共同作用的渐变过程,不同森林发育演替阶段具有不同的林 分特征,对森林经营具有导向作用,好的经营处理能够加快森林生长发展进程;反之,则效果甚微或使森林发展发 生倒退,因此了解经营林分所处的阶段,对提高森林经营水平起着事半功倍的作用。本文把经营条件下的森林发 育演替阶段细分为森林建群、竞争生长、质量选择、近自然林和恒续林5 个阶段。利用逐步判别分析(Wilks' Lambda)对初选的13 个林分指标进行筛选,结果表明:马尾松年龄、平均胸径、大树蓄积比、林分胸高断面积、胸径 变异系数5 个指标能够较好地区分森林发育演替阶段。利用这5 个指标建立Fisher 判别式与Bayes 判别式,结果 表明:2 种判别方法的正判率完全一致,训练样本正判率为94%,验证样本正判率为89%。除此之外,本研究还发 现大树蓄积比是划分森林发育演替阶段的最好指标。

       

      Abstract: Forest growth under management is a gradual process, which is resulted from interaction of nature and man disturbance. Different forest succession stages have specific attributes, playing a guiding role in forest management. Appropriate management can positively affect forest growth, otherwise, the effect is little or even negative. Consequently, identifying forest succession stage has significant influence on improving forest management level. Five forest stages, i. e. forest establishment stage, competition differentiation stage, selection stage, close-to-nature sand naturalness permanent forest stage, were presented based on previous researches. Stepwise discriminant (Wilks' Lambda) was used to select important indices among initial 13 stand indices. Age, average DBH of dominate tree species, ratio of tree volume to total volume, stand basal area, and DBH variable coefficient were selected to classify forest stage. Fisher discriminant function and Bayes discriminant function were established referring to the five indices mentioned above, the classification results were 94% of training samples correctly classified, 89% of verification samples correctly classified, and ratio of tree volume to total volume is the best index to identify forest stage.

       

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