Nondestructive estimation of Pinus taeda L. wood properties for samples from a wide range of sites in Georgia

Abstract

Preliminary studies based on small sample sets show that near infrared (NIR) spectroscopy has the potential for rapidly estimating many important wood properties. However, if NIR is to be used operationally, then calibrations using several hundred samples from a wide variety of growing conditions need to be developed and their performance tested on samples from new populations. In this study, 120 Pinus taeda L. (loblolly pine) radial strips (cut from increment cores) representing 15 different sites from three physiographic regions in Georgia (USA) were characterized in terms of air-dry density, microfibril angle (MFA), and stiffness. NIR spectra were collected in 10-mm increments from the radial longitudinal surface of each strip and split into calibration (nine sites, 729 spectra) and prediction sets (six sites, 225 spectra). Calibrations were developed using untreated and mathematically treated (first and second derivative and multiplicative scatter correction) spectra. Strong correlations were obtained for all properties, the strongest R2 values being 0.83 (density), 0.90 (MFA), and 0.93 (stiffness). When applied to the test set, good relationships were obtained (Rp2 ranged from 0.80 to 0.90), but the accuracy of predictions varied depending on math treatment. The addition of a small number of cores from the prediction set (one core per new site) to the calibration set improved the accuracy of predictions and importantly minimized the differences obtained with the various math treatments. These results suggest that density, MFA, and stiffness can be estimated by NIR with sufficient accuracy to be used in operational settings.

Efecto del raleo sobre las propiedades anatómicas de la madera de Pinus taeda

“…La disminución radial en el valor del AMF también fue señalada por otros autores (Megraw 1985, Bendtsen y Senft 1986, Donaldson 1992, Walker y Butterfield, 1995, Huang et al 1998, Saranpää et al 1998, Herman et al 1999, Yamashita et al 2000, Larson et al 2001, Jones et al 2005, Zhang et al 2007, Winck et al 2013, asociando claramente valores más elevados de ángulo microfibrilar a la presencia de madera juvenil cercana a la médula.…”

OTIMIZAÇÃO DE CALIBRAÇÕES BASEADAS EM ESPECTROSCOPIA NO INFRAVERMELHO PRÓXIMO PARA ESTIMATIVA DE PROPRIEDADES DA MADEIRA DE Eucalyptus

“…O efeito do pré-tratamento espectral provocou redução do erro padrão da predição e aumento da relação de desempenho de desvio das calibrações. Jones et al (2005) estudaram a densidade básica de 120 amostras de Pinus taeda a partir dos espectros puros no NIR e encontraram R² de 0,82, SEP de 0,551 g/cm³ e RPD de 1,89. Esses pesquisadores mostraram que a aplicação do pré-tratamento espectral da primeira derivada reduziu o erro padrão da predição (SEP) de 0,551 para 0,458 g/cm³ e aumentou o RPD de 1,89 para 2,28.…”

Discrimination of native wood charcoal by infrared spectroscopy

“…7 In this study the author provides an ample revision of work produced during the 1990s and early 2000 of the uses of NIRS for studies undertaken using wood and paper materials. NIRS has a number of uses in analyzing wood materials, such as: estimating the length of tracheids during the examination of the fibers quality, 8,9 to verify the characteristics of wood treated thermally, 10 to monitor wood structures that are currently in use, 6 to estimate the chemical composition of Pinus taeda L., 11 of Pinus pinaster Aiton 12 and of Eucalyptus camaldulensis. 13 Also the method is applied in the detection inorganic preservatives such as CCA -copper, chromium and arsenic, ACZA -arsenic, copper, zinc in ammonia solution, 14 boron 15 and copper salts.…”

“…16 Other applications relate to the estimation of mechanical properties of wood logs and wood composites. 9,17,18 The majority of publications concerned with performing NIRS on wood aim to reduce the time of obtaining quantitative results, where spectral data are always associated with multivaried analysis (MVA) techniques. However, less common are studies involving the use of NIRS in discriminating types of wood.…”