Construction of tree volume tables for trembling aspen in Antalya forest region

Abstract

The one of the essential building blocks in forest growth and yield prediction models is the equations for estimating individual tree volume. Individual volume functions estimate wood volume using tree variables that are easy to measure such as diameter at breast height (d) and total height (h). In this study, a local single and double entry volume table was formed for natural grown Trembling Aspen (Populus tremula L.) Antalya forest region. A total of 25 tree volume models were tested for single-entry (11) and double-entry (13) tables in creating the tree volume table. Bias of selected best model 1 and model 12 were 0.010 m3 and 0.005 m3 respectively. Average absolute bias were 0.088 m3 and 0.085 m3, absolute errors were 21.327% and 17.089%, total errors were 2.516% and 0.620%; standard deviation of the residuals were 0.146 m3 and 0.137 m3; determination coefficients were 0.907 and 0.936 for the first and second models, respectively. Obtained values from these two volume functions were performed with paired t-test against an independent set of data, and it was concluded that they were suitable for trembling aspen with a 99.9% confidence.

Keywords

• tek ve çift girişli ağaç hacim tablosu
• hacim fonksiyonları
• regresyon yöntemi
• single and double entry tree volume tables
• volume functions
• regression method