Cherelli Sabrina G, Sartori Maria Márcia P, Próspero André G, Ballarin Adriano W
Universidade Estadual Paulista/UNESP, Departamento de Engenharia Rural, Fazenda Lageado, Rua José Barbosa de Barros, 1780, 18603-970 Botucatu, SP, Brazil.
Universidade Estadual Paulista/UNESP, Departamento de Produção e Melhoramento Vegetal, Fazenda Lageado, Rua José Barbosa de Barros, 1780, 18603-970 Botucatu, SP, Brazil.
An Acad Bras Cienc. 2018 Jan-Mar;90(1):425-438. doi: 10.1590/0001-3765201820160195.
This study evaluated the quality of heartwood and sapwood from mature trees of three species of Eucalyptus, by means of the qualification of their proportion, determination of basic and apparent density using non-destructive attenuation of gamma radiation technique and calculation of the density uniformity index. Six trees of each species (Eucalyptus grandis - 18 years old, Eucalyptus tereticornis - 35 years old and Corymbia citriodora - 28 years old) were used in the experimental program. The heartwood and sapwood were delimited by macroscopic analysis and the calculation of areas and percentage of heartwood and sapwood were performed using digital image. The uniformity index was calculated following methodology which numerically quantifies the dispersion of punctual density values of the wood around the mean density along the radius. The percentage of the heartwood was higher than the sapwood in all species studied. The density results showed no statistical difference between heartwood and sapwood. Differently from the density results, in all species studied there was statistical differences between uniformity indexes for heartwood and sapwood regions, making justifiable the inclusion of the density uniformity index as a quality parameter for Eucalyptus wood.
本研究通过对三种桉树成熟树木的心材和边材比例进行鉴定、运用伽马射线无损衰减技术测定基本密度和视密度，并计算密度均匀性指数，来评估其质量。实验方案中使用了每种树种的六棵树（巨桉——18年树龄、细叶桉——35年树龄和柠檬桉——28年树龄）。通过宏观分析界定心材和边材，并使用数字图像计算心材和边材的面积及百分比。按照对木材沿半径方向围绕平均密度的点密度值离散程度进行数值量化的方法计算均匀性指数。在所研究的所有树种中，心材的百分比均高于边材。密度结果显示心材和边材之间无统计学差异。与密度结果不同的是，在所研究的所有树种中，心材和边材区域的均匀性指数存在统计学差异，这使得将密度均匀性指数作为桉树木材的质量参数具有合理性。
