ABSTRACT

Because of the species similarity and the need to differentiate wood of the Myrtaceae family, this study aimed to evaluate the potential of near-infrared spectroscopy for discrimination of wood and charcoal from Campomanesia xanthocarpa Berg, Eugenia pyriformis Cambess., Myrcia retorta Cambess. and Plinia peruviana (Poir.) Govaerts, native of the Araucaria Forest. For each evaluated species, three trees were collected and a disk at breast height was cut and divided into samples obtained in the region near the pith, intermediate and near the bark. For each sample, two spectra were obtained in each anatomical section (transversal, radial and tangential) in the region from 4000 to 10,000 cm⁻¹. Results indicated the similarity of wood and charcoal spectra of all species, and principal component analysis (PCA) of raw data on samples showed little distinction of species, but second derivative pretreatment provided adequate discrimination. When evaluation was based on anatomical sections and position in trunk, for wood in all positions (near bark, intermediate, near pith) it was possible to separate species, but for charcoal some more samples dispersion were observed. Linear discriminant analysis corroborated the results of PCA. Near-infrared spectroscopy presented adequate results and the potential to help discriminate wood and charcoal of the four Myrtaceae species.

摘要

由于物种的相似性以及对桃金娘科的木材进行区分的需要，本研究旨在评估近红外光谱法鉴别来自坎波马尼亚xanthocarpa Berg，Eugenia pyriformis Cambess。，Myrcia retorta Cambess的木材和木炭的潜力。和Plinia peruviana（Poir。）Govaerts，原产于南洋杉森林。对于每个评估物种，收集了三棵树，并在胸高处切开了一个圆盘并将其分成在靠近髓，中间和靠近树皮的区域中获得的样品。对于每个样品，在4000至10,000 cm ^-1的区域中的每个解剖部分（横向，径向和切向）中均获得了两个光谱。。结果表明所有物种的木材和木炭光谱相似，样品的原始数据的主成分分析（PCA）几乎没有物种差异，但是二阶导数预处理提供了足够的区分度。当基于解剖部位和树干位置进行评估时，对于所有位置的木材（近树皮，中间，近髓），都可以将物种分开，但对于木炭，则观察到更多的样品分散。线性判别分析证实了PCA的结果。近红外光谱显示了足够的结果，并有可能帮助区分四个桃金娘科的木材和木炭。