EFFECT OF AGE AND CLONE ON THE QUALITY OF Eucalyptus spp WOOD AIMING BIOENERGY PRODUCTION

Abstract

O objetivo deste trabalho foi avaliar o efeito da idade e clone na qualidade da madeira de Eucalyptus spp visando \ue0 produ\ue7\ue3o de carv\ue3o vegetal e bioenergia. Foram avaliados quatro clones de Eucalyptus spp nas idades de 57 e 69 meses. Foram amostradas quatro \ue1rvores por clone em cada idade. Determinou-se a densidade b\ue1sica m\ue9dia, a densidade b\ue1sica no DAP, o poder calor\uedfico superior e os teores de lignina, extrativos totais, cinzas, holocelulose e a an\ue1lise qu\uedmica elementar (C, H, N, S e O). Na avalia\ue7\ue3o do experimento utilizou-se um delineamento inteiramente casualizado em um esquema fatorial 4 x 2. Al\ue9m disso, foi realizada a an\ue1lise multivariada de componentes principais. Observou-se, de maneira geral, efeito da idade na qualidade da madeira. Os teores de cinzas, hidrog\ueanio e nitrog\ueanio tenderam a diminuir com o aumento da idade para todos os clones avaliados. J\ue1 o teor de oxig\ueanio apresentou um acr\ue9scimo com a idade dos clones. O teor de lignina apresentou significativo aumento com a idade, sendo o contr\ue1rio observado para o teor de holocelulose. Os clones de 69 meses apresentaram os maiores teores de lignina, mas n\ue3o os maiores valores para a densidade b\ue1sica da madeira. J\ue1 os clones I144 e I220 apresentaram os maiores valores m\ue9dios para essa caracter\uedstica, o que pode ser ben\ue9fico para a produ\ue7\ue3o de carv\ue3o vegetal.The aim of this work was to evaluate the effect of age and clone on the quality of Eucalyptus spp wood aiming the production of charcoal and bioenergy. Four Eucalyptus spp clones at the ages of 57 and 69 months were evaluated. Four trees per clone in each age were evaluated. The average basic density, the basic density at the DBH, higher heating value and contents of lignin, total extractives, ashes, holocellulose an elemental chemica analylsis (C, H, N, S and O) were evaluated. In the evaluation of the assay, and entirely randomized design in the factorial scheme 4 x 2 was used. Besides, a multivariate analysis of main components was made. In general, it was observed effect of age on wood quality. Ash, hydrogen and nitrogen contents tended to diminish with increases in age for all the clones evaluated. However, oxygen content presented an increase with the increase in age of the clones. Lignin content presented significant increase with age increase, being the contrary observed for holocellulose content. The clones at the age of 69 months presented the highest contents of lignin, but the same did not happen for basic density of wood. The clones I144 and I220 had the highest average values for this characteristic, what may be advantageous for charcoal production