Abstract

Standardizing gross volume increment on periodic height increment of the dominant trees is a means of minimizing the effects of site quality and age in growth–growing-stock relations; however, volume increment per height increment contains more information than just a normalization method for fitting growth models. This study builds on previous work suggesting that the cumulative sum of the ratios between individual-tree volume increment and height increment may be a direct measure of stand density. We used data from several levels of growing-stock studies for Douglas-fir, ponderosa pine, and red pine to explore this hypothesis. Regression analysis indicated that the sum of the ratios is proportional to(Dqx⋅N), the underlying equation form of Reineke’s stand density index. Stem growth is a function of canopy dynamics, and additional analyses showed that volume added per unit of height growth was also related to canopy architecture, increasing with decreasing live-crown ratio and increasing foliage density. The linkages between growth, canopy architecture, intermediary canopy dynamics, and (Dqx⋅N) support the hypothesis that the sum of the tree ratios between volume increment and height increment is a direct measure of site occupancy due to its association between growth and corresponding resource use.

中文翻译：

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基于林分生长的林分密度直接测量

摘要

将总体积增量与优势树的周期性高度增量标准化，是一种将站点质量和年龄对生长-生长-种群关系的影响最小化的方法。但是，每个高度增量的体积增量所包含的信息不仅仅是用于拟合生长模型的规范化方法。这项研究建立在以前的工作的基础上，暗示单棵树体积增加量与高度增加量之比的累积和可能是林分密度的直接度量。我们使用道格拉斯冷杉，黄松和赤松的几种不同水平的畜牧研究数据来探索这一假说。回归分析表明，比率之和与Reineke林分密度指数的基本方程形式（Dqx·N）成正比。茎的生长是冠层动态的函数，另外的分析表明，单位高度生长增加的体积也与冠层结构有关，随活冠率的降低和叶面密度的增加而增加。生长，冠层结构，中间冠层动力学和（Dqx⋅N）之间的联系支持以下假设：由于体积增长和高度增长之间的树比之和是增长与相应资源之间的关联，因此其比率是场地占用的直接度量。利用。