An individual-tree dbh-total height model with random plot effects for shortleaf pine (2007)Budhathoki, C. B., Lynch, T. B., & Guldin, J. M. (2008). Nonlinear mixed modeling of basal area growth for shortleaf pine. Forest Ecology and Management, 255(8), 3440-3446. Retrieved from http://www.sciencedirect.com/science/article/pii/S0378112708001941 Individual tree measurements were available from over 200 permanent plots established during 1985-1987 and later remeasured in naturally regenerated stands of shortleaf pine (Pinus echinata Mill.) in western Arkansas and eastern Oklahoma. The objective of this study was to model shortleaf pine growth in natural stands for the region. As a major component of the shortleaf modeling effort, an individual-tree diameter at breast height (DBH)-total height model was developed in which random parameters were estimated for plots. The model predicts total tree height based on DBH and dominant stand height (which could be obtained from a site index model). The mixed-effects model approach was found to predict the total height better than similar models developed previously for this species. Moreover, such a model has the appeal of generalization of the results over a region from which the plots were sampled; and also of calibration of parameters for stands with minimal measurements
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