CARACTERÍSTICAS DAS DIMENSÕES DAS FIBRAS E ANÁLISE DO ÂNGULO MICROFIBRILAR DE Toona ciliata CULTIVADA EM DIFERENTES LOCALIDADES

Abstract

ResumoO presente trabalho teve como objetivos determinar as dimensões das fibras e avaliar o ângulo microfibrilar da madeira de cedro australiano aos 4 anos de idade, no sentido axial base-topo, proveniente dos municípios de Cana Verde, Campo Belo e Santo Antônio do Amparo, localizados na região do sul de Minas Gerais. A partir da altura comercial de cada árvore, foi retirada uma tábua com 5 m de comprimento, da qual foram retiradas amostras em três posições: base, 50 e 100%. Os elementos anatômicos foram mensurados por meio de análise de imagens. Conclui-se que a correlação do AMF com a parede e lume das fibras foi positiva, sendo negativa apenas a interação AMF com o comprimento das fibras em Cana Verde. Em Santo Antônio do Amparo a correlação foi baixa. Não houve um padrão definido da variação no ângulo microfibrilar com as dimensões das fibras no sentido axial por município. As dimensões das fibras apresentaram características semelhantes às do eucalipto. Estudos complementares são necessários para um melhor direcionamento do uso da espécie. Palavras-chave: Dimensões das fibras; ângulo microfibrilar; Toona ciliata. AbstractFibers dimensions characteristics and microfibril angle analisys of Toona ciliata cultivated at different places. The objective of this work was to determine the fibers dimensions and to evaluate the microfibril angle of the wood of Australian cedar with 4 years of age, in the axial direction base-top, proceeding from the municipal districts of the Cana Verde, Campo Belo and Santo Antonio do Amparo, located in the region of the South of Minas Gerais. From the commercial height of each tree, a board with 5 m of length was removed, from this board it was taken samples in three positions: base, 50 and 100%. The anatomical elements were measured through image analysis. Concluded that: the correlation of the AMF with the wall and fire of fibers dimensions was positive and negative only interaction AMF with the fiber length in municipal districts of Cana Verde and in Santo Antonio do Amparo, was low. Top for municipal district did not have a definite standard of variation in the microfibril angle with the fibers dimensions in the axial direction from municipal district. The fibers dimensions presented similar characteristics of the eucalipto. Complementary studies are necessary for one better aiming of the use of the species.

Propriedades físicas, químicas e mecânicas da madeira de cedro australiano cultivado em Corupá, SC

“…Em Adrianópolis, PR, plantios de 11 anos chegaram a atingir 43 cm de DAP (Ricken et al, 2011). Em plantios mais jovens com apenas quatro anos de idade, em Minas Gerais Ziech (2008) obteve DAP médio de 17,5 cm e altura média de 11,4 m. Embora se trate de uma espécie com grande potencial para a silvicultura comercial brasileira, ainda pouco se sabe sobre os aspectos tecnológicos de sua madeira, principalmente com referência à espécie introduzida nos reflorestamentos no Brasil (Ribeiro et al, 2011).…”

Variation in wood properties of 26-year-old Handroantus impetiginosus cultivated in Luiz Antônio, SP

“…However, in populations of Toona ciliata from three different locations, it was found, in relation to the results of the analyzes carried out in the base-top positions of the trees, for the microfibril angle that these differ from those found in the literature, as MFA from the three locations increased in the axial direction, in the bottom-top direction, and this can be explained by the silvicultural and environmental influences that may have occurred (Ribeiro et al, 2011).…”

Radial variation of wood density and fiber morphology of two commercial species in a tropical humid forest in Southeastern Peru

“…Tropical species such as Anadenanthera peregrina, Ochroma pyramidale, and Schizolobium parahyba Var amazonicum showed the same type of increasing radial variation from pith to bark as J. copaia (Rueda and Williamson, 1992;Valente et al, 2013;Lobão et al, 2012) and the same behavior was found in tropical forest plantation species such as Guazuma crinita, Schizolobium parahyba, Tectona grandis, Toona ciliata, (Chavesta et al, 2020;Lima et al, 2021;Melo et al, 2018;Ribeiro et al, 2011). On the other hand, the tropical species Cariniana legalis also did not present any significant trend of radial variation in the pith-bark direction, the same as the species H. crepitans (Lima et al, 2011;Ribeiro et al, 2011), which does not exist a significant difference in the radial variation of wood in the species H. crepitans is favorable for industrial transformation processes (Plaster et al, 2008;Rios et al, 2018).…”