Variabilidad radial física y anatómica del leño de árboles de Amburana cearensis

There are few studies related with X-ray micro-densitometry regarding wood from native tropical forests. The objective of this study was to determine the radial variation of the apparent density of the Amburana cearensis wood by X-ray micro-densitometry. Indeed, eleven trees were selected, in which radial sections were cut from the pith to the cortex, in order to determine the apparent density and the anatomical characteristic in three radial positions. The results showed that the wood of A. cearensis presented mean values of wood density, minimum and maximum of 0.16 and 0.87 g.cm-3 respectively. Moreover, the wood showed significant difference in three positions of the pith, (intermediate and cortex), and this difference can be explained by the microscopic anatomy, especially with the vessels (diameter, area and number.mm-2). X-ray micro-densitometry is an important tool in the radial evaluation of wood and can help in the definition of the growth rings’ limits of A. cearensis.Existen pocos estudios relacionados con microdensitometría de rayos X en madera de bosques tropicales nativos. Este estudio tuvo como objetivo determinar la variación radial de la densidad aparente del leño de Amburana cearensis (Allemão) A.C.Sm. por microdensitometría de rayos X. Se seleccionaron 11 árboles, de los que se cortaron secciones radiales de la médula a la corteza, para establecer la densidad aparente y las características anatómicas en tres posiciones radiales. Los resultados mostraron que la madera de A. cearensis presentó valores medios de densidad de madera, mínimo y máximo de 0.55, 0.13 y 0.87 g.cm-3,respectivamente. Asimismo, mostró diferencia significativa en tres posiciones médula (intermedia y corteza), esta diferencia puede ser explicada por la anatomía microscópica, especialmente con los vasos (diámetro, área y el número.mm-2). La microdensitometría de rayos X es una herramienta importante en la evaluación radial de la madera y puede ayudar en la definición de los límites de los anillos de crecimiento de A. cearensis

Variabilidad radial física y anatómica del leño de árboles de Amburana cearensis

Existen pocos estudios relacionados con microdensitometría de rayos X en madera de bosques tropicales nativos. Este estudio tuvo como objetivo determinar la variación radial de la densidad aparente del leño de Amburana cearensis (Allemão) A.C.Sm. por microdensitometría de rayos X. Se seleccionaron 11 árboles, de los que se cortaron secciones radiales de la médula a la corteza, para establecer la densidad aparente y las características anatómicas en tres posiciones radiales. Los resultados mostraron que la madera de A. cearensis presentó valores medios de densidad de madera, mínimo y máximo de 0.55, 0.13 y 0.87 g.cm-3,respectivamente. Asimismo, mostró diferencia significativa en tres posiciones médula (intermedia y corteza), esta diferencia puede ser explicada por la anatomía microscópica, especialmente con los vasos (diámetro, área y el número.mm-2). La microdensitometría de rayos X es una herramienta importante en la evaluación radial de la madera y puede ayudar en la definición de los límites de los anillos de crecimiento de A. cearensis

Wood species identification from Atlantic forest by near infrared spectroscopy

Aim of study: Fast and reliable wood identification solutions are needed to combat the illegal trade in native woods. In this study, multivariate analysis was applied in near-infrared (NIR) spectra to identify wood of the Atlantic Forest species.Area of study: Planted forests located in the Vale Natural Reserve in the county of Sooretama (19 ° 01'09 "S 40 ° 05'51" W), Espírito Santo, Brazil.Material and methods: Three trees of 12 native species from homogeneous plantations. The principal component analysis (PCA) and partial least squares regression by discriminant function (PLS-DA) were performed on the woods spectral signatures.Main results: The PCA scores allowed to agroup some wood species from their spectra. The percentage of correct classifications generated by the PLS-DA model was 93.2%. In the independent validation, the PLS-DA model correctly classified 91.3% of the samples

Dendrochronology and growth of Copaifera langsdorffii wood in the vegetation dynamics of the Pirapitinga Ecological Station, state of Minas Gerais, Brazil

This study aims to build a chronology of the growth rings of Copaifera langsdorffii (copaíba) in order to understand the dynamics of vegetation types that occur on a river island in the Cerrado biome. For this purpose, we selected 30 trees of copaíba established in a vegetation of Mata Seca Sempre-Verde in the Pirapitinga Ecological Station (EEP), state of Minas Gerais, Brazil. Two radial samples from each tree were collected by an auger. The samples were treated by mechanical polishing for better visualization of the growth rings, and consequently further delineation and measurement. Later, the width of the growth rings was verified in order to generate a master time series of the specie. To check the influence of meteorological factors, we used the Pearson correlation (p < 0.05). The results showed that the population of copaíba in the EEP presented dendrochronologyc potential, which was confirmed by the high values of wide growth rings correlation within and between trees. The dendrochronologyc analysis revealed that copaíba trees were already present before the dam filling, but with lower population density than today. It was also possible to infer that the development of the vegetation type Mata Seca Sempre-Verde occurred since the decade of the 1970. The average sensitivity was enough to consider the species sensitive to environmental variations. Precipitation and temperature only influenced positively the growth rings in the transition from dry to wet seasons. The results revealed information about the dynamics of the local vegetation, elucidating the changes that occurred in the environment in which the population of copaíba is established