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Báo cáo lâm nghiệp:"Analysis of log shape and internal knots in twenty Maritime pine (Pinus pinaster Ait.) stems based on visual scanning and computer aided reconstruction"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài:"Analysis of log shape and internal knots in twenty Maritime pine (Pinus pinaster Ait.) stems based on visual scanning and computer aided reconstruction" | Ann. For. Sci. 60 2003 137-144 INRA EDP Sciences 2003 DOI 10.1051 forest 2003006 137 Original article Analysis of log shape and internal knots in twenty Maritime pine Pinus pinaster Ait. stems based on visual scanning and computer aided reconstruction Isabel Pintoa Helena Pereirab and Arto Useniusa a VTT Building and Transport PO Box 1806 02044 VTT Finland b Centro de Estudos Florestais Instituto Superior de Agronomia 1349-017 Lisboa Portugal Received 1 February 2001 accepted 21 January 2002 Abstract - A mathematical reconstruction of Maritime pine Pinus pinaster Ait. was produced using the WoodCim software based on input information obtained by image scanning of twenty 83 years old stems sampled in Portugal. The application of the reconstruction software resulted in 3D and 2D representations for logs and trees that allowed the visual appraisal of external shape as well as of the internal knot architecture. Information on tree geometry i.e. taper and knot parameters i.e. knot length diameter and volume and on their variation with tree height could be obtained from the reconstructed logs and stems and may be incorporated in sawing yield studies through simulation as well as in raw material characterisation studies. In the studied trees the average volume percentage of knots varied from 0.07 for butt logs to 1.95 for top logs. The knot core represented in of the tree radius from 28 at the stem bottom to 84 at 70 of total tree height. maritime pine modelling wood quality knot dimensions image analysis Résumé - Caractérisation de la forme des futs et des noeuds dans 20 arbres de pin maritime Pinus pinaster Ait. après analyse d image et reconstruction par logiciel. La reconstruction mathématique d arbres de pin maritime Pinus pinaster Ait. a été faite avec le logiciel WoodCim ayant pour base l information obtenue par l analyse d image de vingt futs de 83 ans échantillonés au Portugal. L application des modèles de reconstruction a produit des representations en 3D et 2D