Development of the Site Index Curves for <italic>Quercus acuta</italic> Stands

Abstract

Background and objective: The purpose of this study is to develop a model for estimating the site index (SI), which is the criterion for determining the site productivity of the <i>Quercus acuta</i> stand as known as Evergreen broad-leaved tree (EBLT) species.Methods: The materials used in the analysis were data from 63 sample plots, and the sample plots data were collected from the National Forest Inventory (NFI) and other sites. Since the site index is determined by the height and stand age of the dominant trees, the Schumacher model, the Chapman-Richards model, and the Weibull model were applied to derive the optimal equation for estimating the dominant tree height.Results: The three models derived the parameters and went through a statistical test. Among the three models, the Chapman-Richards model was found to be optimal considering the fitness index, bias, and residuals. By transforming this model, site index estimation equations with the reference age of 30 years were created, and site index curves were derived. According to the analysis of the collected data, the site index of the <i>Quercus acuta</i> stand in Korea was found to be in the range of 10 to 16.Conclusion: As the growth distribution of <i>Quercus acuta</i> is expected to move north due to climate change, the derivation of the site index representing site productivity will be helpful in making policy and management decisions for this species.