Influence of the tree and stand parameters in the wood characterizationStudy in natural stands of Quercus robur L. in Galicia (NW Spain)

Resumo

Wood density (WD) and wood shrinkage (WS) are high wood quality indicators, which are an important index of the dimensional stability of wood and wood products, their influence both wood processing and end use is relevant. The problems in the processing and drying could be caused by many factors because the logs processed tend to have diverse moisture content resulting in a different dimensional performance. Trying to get a future visual classification of the wood, according to its dimensional stability and establishing different drying and transformation process, this study tended to estimate these properties by collecting forest information (Stand parameters) and Tree data (Tree parameters). Different trees of Quercur robur L. were sampled in the North-west of Spain and separated in different groups according to Plot, Tree and Height. The discs were taken at different height levels of the stem from 0.30m with an interval of 1m, the disc were cut in different cubes to determinate the wood density and wood shrinkage. The collected data in each site have been sorted in 3 blocks (i) Plot (basal area, dominant height, medium height, number of tree per hectares, site index), (ii) Tree (Competence index �BAL and HART�, volume outside and inside bark, diameter at 1.30 meters, diameter at the beginning the first branch, height, taper function), (iii) Height (Relative height and diameter). In every block, the knowledge of the structural variation of some properties (estimate variance components, correlation between properties�) is essential to analyze the collected data. As a result of those data we could confirm that the differences of both properties, WD and WS, are highly significant. The second phase of this work analyzes the variability along the stem of WD and WS. In this paper, we prove that this variability is nonconstant along the stem. We will show how the WD and WS are distributed in the stem and how they vary from tree to tree and to plot to plot related to the stand and tree parameters examined.