Caracterización anatómica de la madera de Eucalyptus grandis proveniente del este uruguayo

In the Uruguayan forestry industry, the main product is bleached chemical sulphate pulp, with Eucalyptus grandis being the second most planted species. The general objective of this work is to verify the pulpable characteristics of Eucalyptus grandis from a plantation in eastern Uruguay. Among the specific objectives is to determine the basic density of wood and its anatomical properties; analyze the effect of the height and the radial position in the trunk of the specimens on the density and anatomical characteristics; calculate pulp and paper quality indices; relate the indices to those recommended for pulp and paper production. The study included 10 11-year-old trees belonging to the company Redalco S. A., the logs used were obtained at two heights: 1.30 and 2 meters (DAP and API, respectively). Libriform fibers were found, where the variables to be measured were length, width, lumen diameter, fiber area and wall thickness. Regarding the two heights, no significant differences were found, however, there were significant differences for the radial positions in the diameter of the lumen and fiber area, in the interaction height x position the differences were in the length and width of the fiber. The woody vessels were arranged solitary, with a diffuse porosity, in the radial position the differences were in the tangential diameter and frequency, while in the height x position interaction they were in area and vessel length. The rays were mostly uniseriate and homogeneous; the average for the frequency in linear mm was 13.94, the height 193.96 µm and 9.51 cells. There were no significant differences in height, radial position, or in the height x position interaction. The density presented an average of 0.381 g.cm-3, a standard deviation of 0.03 and the coefficient of variation was 7.87%. For the Anova analysis, only differences were seen for the radial positions, especially in position A. Coefficients for pulp and paper production were calculated, Runkel Index 0.28, Flexibility Coefficient 0.54, Stiffness Coefficient 43 .01,Wall fraction 15, 43% and Luca Factor 0.542. With the results obtained in the production of pulp and paper with Eucalyptus grandis from the east of the country, they present a pulp with good formation, with paper resistance in relation to traction and bursting.