ABSTRACT Background: The objective of this study was to evaluate the quality indicators for wood and charcoal from the Eucalyptus urophylla x Eucalyptus grandis hybrid (Clone GG 100) in different planting spacings. The study was conducted with the hybrid using the spacings of 2×1, 2×2, 3×2, and 3×3 m. The chemical properties of wood and charcoal were analyzed, and dry wood mass and energy per hectare were estimated. The data were subjected to the t test for comparison of means. Moreover, principal component analysis was conducted to assess the relationships between wood and charcoal indicators as a function of spacing. Results: The 2×2 m spacing showed the highest values for dry wood mass, lignin mass, mass of charcoal, and energy. The wider spacings of 3×2 and 3×3 m resulted in wood and charcoal of increased quality by showing wood of greater resistance to thermal degradation and charcoal of higher yield. Conclusion: Spacing between trees influenced wood quality indicators. The 2×2 m spacing showed higher estimates of mass and energy per hectare. However, wide spacings with an area greater than 6 m2 are more suitable for charcoal production due to their superior wood properties, especially basic density and total lignin, which influence gravimetric yields and bulk density. Background Clone 100 21 2 1 2×1 22 32 3 33 3× analyzed estimated means Moreover Results 2× yield Conclusion However 10

Abstract Forests play a crucial role in the global carbon cycle. Among the factors that can affect carbon stocks in forest stands, planting spacing stands out. This study verified the effect of spacing on biomass and carbon stock in a stand of Anadenanthera peregrina (L.) Speg at 56 months of age. They were planted with 3 x 2 m, 3 x 3 m, 4 x 3 m, 4 x 4 m and 5 x 5 m spacings. The biomass of the above-ground compartments (stem, branches, leaves and bark) and root biomass was quantified, totalling 16.42 and 6.68 Mg ha-1, respectively. The largest amount of biomass and carbon stock occurred in the denser spacings. Total biomass was twice as large at 3 x 2 m spacing compared to 5 x 5 m spacing. The root biomass represented 40.93% of the total biomass. The order of participation of the components in the total aboveground biomass was branches (44.99%), stem (40.77%), leaves (13.99%) and bark (4.90%). The denser spacings (3 x 2 m and 3 x 3 m) showed higher values of biomass and carbon stock than the wide spacings (4 x 3 m, 4 x 4 m and 5 x 5 m). There was no effect of planting spacing on carbon stock in necromass and soil. cycle out L. L (L. age above ground stem, (stem quantified 1642 16 42 16.4 668 6 68 6.6 ha1, ha1 ha 1, 1 ha-1 respectively 4093 40 93 40.93 44.99%, 4499 44.99% , 44 99 (44.99%) 40.77%, 4077 40.77% 77 (40.77%) 13.99% 1399 13 (13.99% 4.90%. 490 4.90% . 90 (4.90%) ( m. soil (L 164 16. 66 6. ha- 409 9 40.9 449 44.99 (44.99% 407 40.77 7 (40.77% 13.99 139 (13.99 49 4.90 (4.90% 40. 44.9 (44.99 40.7 (40.77 13.9 (13.9 4.9 (4.90 44. (44.9 (40.7 13. (13. 4. (4.9 (44. (40. (13 (4. (44 (40 (1

Resumo As florestas desempenham um importante papel no ciclo do carbono. Dentre os fatores que podem afetar os estoques de carbono nos povoamentos florestais, o espaçamento de plantio tem grande relevância. O objetivo foi verificar o efeito do espaçamento na biomassa e no estoque de carbono em um povoamento de Anadenanthera peregrina (L.) Speg aos 56 meses de idade. O povoamento foi implantado nos espaçamentos 3 x 2 m, 3 x 3 m, 4 x 3 m, 4 x 4 m e 5 x 5 m. Quantificou-se a biomassa dos compartimentos acima do solo (madeira, galhos, folhas e casca) e da raiz, totalizando 16,42 e 6,68 Mg ha-1, respectivamente. A maior quantidade de biomassa e estoque de carbono ocorreu nos menores espaçamentos. A biomassa total foi duas vezes maior no espaçamento de 3 x 2 m em comparação com o espaçamento de 5 x 5 m. A biomassa abaixo do solo representou 40,93% da biomassa total. A ordem de participação dos componentes na biomassa aérea total foi galhos (44,99%), madeira (40,77%), folhas (13,99%) e casca (4,90%). Os espaçamentos mais densos (3 x 2 e 3 x 3 m) apresentaram maiores valores de biomassa e estoque de carbono do que os espaçamentos mais amplos (4 x 3 m, 4 x 4 m e 5 x 5 m). Não houve efeito do espaçamento de plantio sobre o estoque de carbono na necromassa e no solo. florestais relevância L. L (L. idade Quantificouse Quantificou se madeira, (madeira raiz 1642 16 42 16,4 668 6 68 6,6 ha1, ha1 ha 1, 1 ha-1 respectivamente 4093 40 93 40,93 44,99%, 4499 44,99% , 44 99 (44,99%) 40,77%, 4077 40,77% 77 (40,77%) 13,99% 1399 13 (13,99% 4,90%. 490 4,90% . 90 (4,90%) ( (L 164 16, 66 6, ha- 409 9 40,9 449 44,99 (44,99% 407 40,77 7 (40,77% 13,99 139 (13,99 49 4,90 (4,90% 40, 44,9 (44,99 40,7 (40,77 13,9 (13,9 4,9 (4,90 44, (44,9 (40,7 13, (13, 4, (4,9 (44, (40, (13 (4, (44 (40 (1

RESUMO O objetivo deste trabalho foi determinar as propriedades de painéis aglomerados confeccionados com partículas de bagaço de cana-de-açúcar in natura e aquecidas a 250 °C durante 5 minutos. Foram empregadas várias proporções de partículas na confecção dos painéis e as suas propriedades foram comparadas com as propriedades de um painel fabricado com partículas de Pinus sp. Os painéis foram produzidos com 8% de adesivo à base de tanino formaldeído, 0,5% de emulsão parafínica e prensados a 32 kgf.cm-2, por 10 minutos, à temperatura de 180 °C. Determinou-se a densidade básica das partículas in natura e termotratadas, sua composição química bem como a taxa de compressão necessária para obter painéis com densidade igual a 0,75 g.cm-3. Determinou-se a densidade básica dos painéis, umidade de equilíbrio higroscópico, inchamento em espessura, expansão linear, adsorção de vapor de água, módulo de elasticidade e de ruptura, tração perpendicular, arrancamento de parafuso e dureza Janka. As densidades básicas das partículas de Pinus e do bagaço de cana sem e com tratamento térmico foram de 0,46, 0,27 e 0,30 g.cm-3, respectivamente. A massa específica média dos painéis foi igual a 0,74 g.cm-3 sem diferença significativa entre eles. Geralmente, os painéis fabricados com partículas de cana-de-açúcar foram menos higroscópicos e dimensionalmente mais estáveis do que os painéis fabricados com partículas de Pinus. Contudo, a resistência à tração perpendicular, o arrancamento de parafuso e a dureza de Janka destes painéis foram maiores. O tratamento térmico das partículas de bagaço de cana resultou em melhores propriedades mecânicas de tração perpendicular e dureza de Janka. De modo geral, os painéis estão dentro dos limites estabelecidos pela norma ANSI A208.1. Portanto, é possível substituir painéis confeccionados com partículas de Pinus por bagaço de cana de açúcar, desde de que, pelo menos 25% das partículas sejam tratadas termicamente durante 5 minutos à temperatura de 250ºC.

ABSTRACT The objective of this work was to determine the properties of particleboard panels made of “in natura” sugarcane bagasse particles, heated at 250 °C for 5 minutes. Various particle proportions were utilized to produce the panels and their properties were compared with that of a panel made of Pinus sp. The panels were produced with 8% tannin formaldehyde adhesive, and 0.5% paraffin emulsion, being pressed at 32 kgf.cm-2 for 10 minutes at 180 ° C. It was determined the basic density of the “in natura” and heat-treated particles, their chemical composition, as well as the compression ratio necessary to obtain panels with density equal to 0.75 g.cm-3. The basic density of the panels, hygroscopic equilibrium humidity, thickness swelling, linear expansion, water vapor adsorption, modulus of elasticity and rupture, perpendicular traction, screw pullout, and Janka hardness were determined. The basic densities of Pinus particles and sugarcane bagasse without and with heat treatment were 0.46, 0.27 and 0.30 g.cm-3, respectively. The average specific mass of the panels was 0.74 g.cm-3 with no significant difference between them. Generally, panels made of sugarcane particles were less hygroscopic and dimensionally more stable than panels made of Pinus particles. However, the perpendicular tensile strength, screw pullout and Janka hardness of these panels were higher than for the Pinus panels. The heat treatment of sugarcane bagasse particles resulted in better mechanical properties of perpendicular traction and Janka hardness. In general, the panels are within the limits set by ANSI A208.1. It is therefore possible to replace panels made of Pinus particles for the ones made of sugarcane bagasse, provided that at least 25% of the particles are heat treated for 5 minutes at 250 ° C.