Accurate estimates of tree bole volume are fundamental to sustainable forest management. Total inside and outside bark and merchantable volume equations were developed for 25 major commercial tree species grown in natural stands in eastern and central Canada and the northeastern United States. Data used to develop these equations was collected from 9647 trees sampled from natural stands across the study area. The number of trees sampled varied among species. Jack pine (Pinus banksiana Lamb.) had the most observations (1648 trees) and American basswood (Tilia americana) and red oak (Quercus rubra L.) had the fewest (28 trees each). Two mathematically consistent volume equations (dimensionally compatible and combined variable) were fitted to inside and outside bark and merchantable tree volume data from these tree species. The final volume equation was selected based on fit statistics, predictive accuracy, and logical consistency. Its predictive accuracy was compared with a volume equation previously developed by Honer. Both (total and merchantable) volume equations were fitted using a nonlinear mixed-effects modelling approach. However, random effects were significant for total volumes for only four tree species. A weight (power function) was used to address heteroscedasticity in the data. The modified form of the dimensionally compatible volume equation outperformed the combined variable volume equation in terms of fit statistics and predictive accuracy and was selected as the total inside and outside bark and merchantable volume equations for all tree species. This equation produced logically consistent estimates of total and merchantable volumes and was more accurate than that previously developed by Honer to estimate volumes for most of the tree species used in this study. This new equation can be used to estimate total inside and outside bark and merchantable volumes of major commercial tree species in eastern and central Canada and the northeastern United States.

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加拿大和美国东北部种植的 25 种商业树种的总体积和可销售体积方程

准确估计树干体积是可持续森林管理的基础。为生长在加拿大东部和中部以及美国东北部的自然林分中的 25 种主要商业树种开发了总内外树皮和可销售体积方程。用于开发这些方程的数据是从整个研究区域的自然林分采样的 9647 棵树中收集的。采样的树木数量因物种而异。杰克松 ( Pinus banksiana Lamb.) 的观察次数最多 (1648 棵树) 和美洲椴木 ( Tilia americana ) 和红橡木 ( Quercus rubra)L.) 最少（每棵 28 棵树）。两个数学上一致的体积方程（尺寸兼容和组合变量）被拟合到来自这些树种的内部和外部树皮和可销售树木体积数据。根据拟合统计、预测准确性和逻辑一致性选择最终体积方程。将其预测准确性与 Honer 先前开发的体积方程进行了比较。使用非线性混合效应建模方法拟合（总体积和可销售）体积方程。然而，只有四种树种的总体积随机效应显着。权重（幂函数）用于解决数据中的异方差问题。尺寸兼容体积方程的修改形式在拟合统计和预测精度方面优于组合可变体积方程，并被选为所有树种的总内外树皮和适销体积方程。该方程对总体积和可销售量产生了逻辑上一致的估计，并且比 Honer 之前开发的用于估计本研究中使用的大多数树种的体积更准确。这个新方程可用于估计加拿大东部和中部以及美国东北部主要商业树种的内外总树皮和可销售量。该方程对总体积和可销售量产生了逻辑上一致的估计，并且比 Honer 之前开发的用于估计本研究中使用的大多数树种的体积更准确。这个新方程可用于估计加拿大东部和中部以及美国东北部主要商业树种的内外总树皮和可销售量。该方程对总体积和可销售量产生了逻辑上一致的估计，并且比 Honer 之前开发的用于估计本研究中使用的大多数树种的体积更准确。这个新方程可用于估计加拿大东部和中部以及美国东北部主要商业树种的内外总树皮和可销售量。