tailieunhanh - Báo cáo lâm nghiệp: "Radial variation of wood density components and ring width in cork oak trees"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Radial variation of wood density components and ring width in cork oak trees. | Ann. For. Sci. 64 2007 211-218 INRA EDP Sciences 2007 DOI forest 2006105 211 Original article Radial variation of wood density components and ring width in cork oak trees Sofia KNAPlCa José L. L0UZADAb Sofia LEALa Helena PERElRAa a Centro de Estudos Florestais Institute Superior de Agronomia Universidade Técnica de Lisboa Tapada da Ajuda 1349-017 Lisboa Portugal b Departamento Florestal Universidade de Trás-os-Montes e Alto Douro Portugal Received 15 February 2006 accepted 24 October 2006 Abstract - The radial variation of ring width and wood density was studied in cork oaks Quercus suber using microdensitometry. The observations were made in young never debarked cork oaks 30-40 years of age and in mature trees under cork production 37-60 years of age . The cork oak wood is very dense mean ring density between and with a small intra-ring variability mean earlywood density and latewood density . The density components decreased from pith to bark more rapidly until the 15th ring and then only slightly. There were no significant differences in the mean density components between never debarked trees and trees under cork production but their outwards decrease was accentuated in the never debarked trees. The annual growth was high with a ring width mean of mm mm in the first 30 years and the latewood represented 57 of the annual growth. Quercus suber cork oak density ring width latewood Résumé - Variation radiale des composantes de la microdensité du bois et de la largeur de cerne dans le chêne-liège. La variation radiale de la largeur des cernes et de la densité du bois a été étudiée dans le chêne-liège Quercus suber par microdensitométrie. Les observations ont été réalisées dans des arbres jeunes jamais écorcés âge 30-40 ans et des arbres en phase de production de liège 37-60 ans . Le bois de chêne-liège est très dense densité moyenne 0 86 variant entre 0 79 et 0 97 avec .