A new approach to project stand tables

Abstract

Recent research studies have shown that an integrated system can be constructed to provide future predictions when the inputs are from plot summary, a tree list, or a diameter distribution. The current study addresses the missing link, allowing this integrated system to also accept inputs from a stand table. In this study, different existing techniques were employed to process data in stand table format. Trees in each diameter class were modeled with a truncated Weibull distribution. A tree list was generated by dividing each diameter class into 0.2-cm sub-classes, the midpoint diameter of which represented diameter of an individual tree. Projecting the stand table was equivalent to growing trees in the tree list. Future tree survival and diameter growth were predicted by use of an individual-tree model, which was derived from a whole-stand model. This new method outperformed three existing stand table projection models, based on two error indices.