Características dendrométricas de eucalipto submetido a desbaste

Abstract

Thinning is a silvicultural technique that aims to produce high quality wood by obtaining large trees in a shorter time, changing the dendrometric characteristics of the remaining trees. Thus, the objective was to present the changes in the dendrometric characteristics, besides adjusting and selecting hypsometric models for a eucalyptus stand subjected to different intensities of systematic thinning. The treatments were: T0: control (without thinning); T25: reduction of 25% in the number of individuals; T33: reduction of 33%; and T50: 50% reduction. The stand was measured at 60 months (before intervention), 67, 74, 81, 88 and 95 months. The dendrometric variables evaluated were diameter at breast height (DBH), total height (Ht), mortality and basal area per hectare. The hypsometric models tested were Stoffels, Linear and Curtis Models. The model identity test was applied to verify the possibility of a single equation representing the hypsometric relation for the treatments within the same age. Thinning influenced growth in DBH and basal area per hectare, but there was little influence on total height growth. Mortality was lower than 3.3% for all treatments, except for T50 which was 7%. The Curtis model resulted in the best total height estimates. Thinning provided changes in the diametric increments of the treatments resulting in the impossibility ofusing a single hypsometric equation for the different treatments at each age.