ESTIMATION OF TRACHEID MORPHOLOGICAL CHARACTERISTICS OF GREEN PINUS TAEDA L. RADIAL STRIPS BY NEAR INFRARED SPECTROSCOPY

摘要

The application of near infrared (NIR) spectroscopy to the green wood of radial samples (simulated increment cores) and the development of calibrations for the prediction of several tracheid morphological characteristics are described. Twenty Pinus taeda L. (loblolly pine) radial samples were characterized in terms of coarseness, perimeter, radial and tangential diameter, specific surface, and wall thickness, NIR spectra were obtained in 10-mm steps from the radial-longitudinal and transverse face ofeach sample and were used to generate calibrations for each property NIR spectra were collected from all samples when the wood was green (moisture content ranged from approximately 100 to 154%), and when dried to approximately 7% moisture content. The relationships between measured and NIR-estimates for green wood were strong for coarseness, specific surface, and wall thickness, with coefficients of determination (R~2) ranging from 0.89 to 0.73. Differences between calibrations developed using radial-longitudinal and transverse face NIR spectra were generally small. Dry wood calibrations demonstrated strong relationships for all parameters apart from perimeter and radial diameter; R~2 ranged from 0.59 to 0.91. Calibrations were tested on an independent set; relationships for coarseness, specific surface, and wall thickness were strong. Good calibrations can be obtained for some tracheid morphological characteristics using NIR spectra collected from the surface of green P. taeda wood.