Resumo Na Floresta Ombrófila Mista adicionalmente à diversidade florística, estudos sobre a diversidade anatômica da madeira de espécies nativas são interessantes pois permitem ampliar nosso conhecimento sobre a flora local. Portanto, este trabalho objetivou caracterizar anatomicamente e avaliar as similaridades e as principais características anatômicas que variam entre a madeira de 14 espécies nativas da Floresta Ombrófila Mista, de acordo com IAWA (1989). Foram utilizadas 14 variáveis anatômicas para aplicar os métodos de similaridade de Manhattan e Análise de Componentes Principais (PCA). Como resultados, pode-se observar que as espécies apresentam características comuns, como a porosidade difusa e pontoações intervasculares alternas. Além disso, a presença de fibras septadas e parênquima axial escasso em 50% das madeiras, foram características marcantes para as espécies da região. Quanto à similaridade, observou-se a divisão das mesmas pelas dimensões dos raios, vasos e pontoções. No PCA, destacaram-se o diâmetro do vaso, largura e altura do raio, a altura do raio em número de células, as pontoações intervasculares e raio-vasculares. Pode-se concluir que, mesmo com a grande diversidade anatômica é possível diferenciar a madeira das espécies da Floresta Ombrófila Mista, que ocorrem naturalmente na região do Planalto Catarinense.

Abstract In the Araucaria Forest in addition to floristic diversity, studies on the anatomical diversity of wood of native species are required. Therefore, this work aimed to characterize anatomically and evaluate the similarities and the main anatomical characteristics that vary between the wood of 14 native species of the Araucaria Forest. For the characterizations, the procedures determined by IAWA (1989) were followed. Fourteen anatomical variables were used to apply the Manhattan similarity and Principal Component Analysis (PCA). As result, it can be observed that the species present common characteristics, such as diffuse porosity and alternate intervessel pits. In addition, the presence of septate fibers and axial parenchyma scarce in 50% of the woods were remarkable characteristics for the species of the region. As for the similarity, was observed the division by the dimensions of the rays, vessels and pits. In PCA, the diameter of the vessel, width and height of the radius, the height of the radius in number of cells, the intervessel pits and the radius-vascular were emphasized. In conclusion, even with the great anatomical diversity, it is possible to differentiate the wood from the species of the Araucaria Forest, which occur naturally in the region of Planalto Catarinense.

La madera de teca (Tectona grandis L.f.) es una de las más valiosas en el comercio internacional y una especie importante para la silvicultura tropical. La teca se encuentra en la isla de Timor Leste, pero no existe información disponible sobre su crecimiento en esta región. Se estudió una plantación pura no manejada que fue establecida entre 1940 y 1950 en el Norte de Timor Leste. Entre Octubre- Noviembre 2003 se cosecharon 15 árboles y al tronco se les extrajeron discos a tres niveles de altura (1.7m, 9.5m y 18.7 m), y se recolectaron núcleos a la altura del pecho (DAP). El conteo y la medición de los anillos se realizaron mediante el software de análisis de imagen. La distinción entre el duramen y la albura se realizó macroscópicamente por la diferencia de color, y se midieron el radio del duramen y el ancho de la albura. Para cada disco se estudió la relación entre el tallo y radio del duramen y el porcentaje del duramen. Las curvas de variación del ancho de los anillos se presentan para las diferentes posiciones axiales dentro del tronco y se analizó la variabilidad del ancho de los anillos. Las tasas de crecimiento fueron calculadas y las relaciones de radio con la edad se calcularon usando las curvas de crecimiento acumulado. Los anillos de crecimiento eran grandes y bien definidos en la fase juvenil, lo que refleja el carácter de crecimiento rápido de esta especie. La variación en la anchura de los anillos año a año mostró un patrón similar entre los árboles. La anchura media del anillo osciló entre 4.3-7.3mm para los primeros 20 años y 3.3-5.1mm para los de 30 a 45 años. La excentricidad de la médula fue evidente en la parte inferior del tallo y se observó la formación de anillos sobrepuestos. En promedio, el duramen representó el 84% del radio y la albura mostró entre 6 y 11 anillos. La variación del ancho de los anillos con la edad, la presencia de excentricidad en la parte inferior del árbol y los anillos sobrepuestos pone de relieve la importancia del manejo forestal con particular atención a la distribución de densidad basal en el tiempo, cuando se pretende la producción optimizada de la madera.

Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.

Caracterizaram-se as fibras da madeira e casca da Acacia melanoxylon e compararam-se com as do Eucalyptus globulus, principal espécie usada em Portugal para celulose. Abateram-se vinte árvores da Acacia melanoxylon em quatro locais. Determinou-se o comprimento e a espessura de parede das fibras em elementos dissociados com o soluto de Franklin. A variação radial foi estudada a 10, 30, 50, 70 e 90% do comprimento do raio e a variação axial a 5, 35 e 65% da altura da árvore. Na Acacia melanoxylon, o comprimento das fibras da madeira e casca oscilou entre 0,90 - 0,96 mm e 1,33 - 1,59 mm respectivamente e a espessura da parede variou entre 3,45 - 3,89 µm na madeira e 5,01 - 5,40 µm na casca. O comprimento das fibras diminuiu da base para o topo da árvore. O comprimento e a espessura de parede aumentaram radialmente, embora a espessura com algumas flutuações. Axialmente a espessura da parede não mostrou um padrão específico de variação. Na Acacia melanoxylon o comprimento das fibras da casca e a espessura da parede das fibras da madeira apresentaram diferenças significativas entre locais. As fibras são semelhantes às do Eucalyptus globulus, embora mais finas na madeira e mais espessas na casca. O padrão de variação radial é semelhante nas duas espécies. No Eucalyptus globulus, a espessura da parede das fibras da madeira aumenta até meio da altura da árvore e depois diminui para o topo; na casca diminui da base para o topo. No Eucalyptus globulus as fibras da casca são maiores no topo.

Wood and bark fibers of Acacia melanoxylon were characterized and compared to Eucalyptus globulus which is a major quality source of pulp fibers. In 20 trees from four sites, fiber length and wall thickness were measured at 5, 35 and 65% of total tree height and at 10, 30, 50, 70 and 90% of the distance from pith. Maceration were prepared in a 1:1 glacial acetic acid:hydrogen peroxide solution. Wood and bark fiber length varied between 0.90 - 0.96 mm and 1.33 - 1.59 mm respectively. The cell wall thickness varied between 3.45 - 3.89 µm in wood and 5.01 - 5.40 µm in bark. Wood and bark fiber length decreased from the bottom to the top of the tree and cell wall thickness had no specific pattern for axial variation. Fiber length and wall thickness increased from the pith to the bark, but the wall thickness increased slightly with some fluctuations. In Acacia melanoxylon significant site differences were found in relation to bark fiber length and to wood wall thickness. The fibers of Acacia melanoxylon were similar to those of Eucalyptus globulus but the wood fibers were thinner and the bark fibers thicker. The radial variation was similar in both species. In wood of Eucalyptus globulus, fiber wall thickness increases from the base to the middle of tree height and decreases to the top; in the bark decreases from the base to the top. In Eucalyptus globulus fibers bark are higher in the top.