Abstract Modeling the productive capacity of forest sites from biophysical factors is important when site-dominant height data is not available. For this reason, we aim with this study to model the mean annual volume increment at age 7 (MAI7) of Eucalyptus clonal plantations, to evaluate the accuracy of the modeling, and to fit an empirical equation. For this, we used data from twenty-two variables collected in 51 plots distributed randomly in three classes of MAI7 predicted. Initially, Spearman’s rank correlation was used for primary mining of these variables, then principal components analysis (PCA) was used to create orthogonal latent variables that were used as input in the artificial neural network (ANN) to MAI7 predict. Spearman’s and PCA analysis proved to be excellent for data mining because when used together were enabled to reduce the number of variables and create a variable that represented the maximum variance of the variables which were significantly associated with the MAI7. All ANN trained exhibited high learning capability when using as input to the latent variables created in conjunction with the classes of MAI7, but the ANN trained with architecture 6-9-1 made prediction with greater precision for the test set and too showed high accuracy to the train set. Therefore, combining PCA with ANN was an excellent approach to developing an empirical equation to accurately predict MAI7 of clonal plantings of hybrid of Eucalyptus located in the southeast of Para State, Brazil from biophysical variables.

中文翻译：

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结合主成分分析和人工神经网络从生物物理属性模拟桉树林分的生产能力

摘要 当站点主导高度数据不可用时，根据生物物理因素对森林站点的生产能力进行建模很重要。因此，我们的研究旨在模拟桉树无性系人工林 7 龄 (MAI7) 的平均年产量增量，以评估建模的准确性，并拟合经验方程。为此，我们使用了 51 个地块中收集的 22 个变量的数据，这些数据随机分布在预测的 MAI7 的三类中。最初，Spearman 秩相关用于这些变量的初步挖掘，然后使用主成分分析 (PCA) 创建正交潜在变量，这些变量用作人工神经网络 (ANN) 中对 MAI7 预测的输入。事实证明，Spearman 和 PCA 分析非常适合数据挖掘，因为当一起使用时，可以减少变量数量并创建一个变量，该变量代表与 MAI7 显着相关的变量的最大方差。当使用与 MAI7 的类一起创建的潜在变量作为输入时，所有训练的 ANN 都表现出很高的学习能力，但是使用架构 6-9-1 训练的 ANN 对测试集进行了更高精度的预测，并且也表现出很高的准确性火车组。因此，将 PCA 与 ANN 相结合是开发经验方程的一种极好方法，可以根据生物物理变量准确预测位于巴西帕拉州东南部的桉树杂交种的克隆种植 MAI7。