Identification of common wood species in northeast China using Vis/NIR spectroscopy

To determine the feasibility of using visible/near infrared spectroscopy to identify wood samples drilled using an increment borer, and to provide a method of wood identification in the wild, 14 wood species typically found in Northeast China were sampled and drilled with an increment borer through 1.3 m breast-height of the trees from south to north, the samples are about 300 mm in length and 5 mm in diameter. Analysis included use of derivative, logarithmic, and smooth processing to process the wood spectrum and used a distance method to build the identification model. Results showed that without smoothing, the accuracy rate of the first derivative (96.79%) was much better than the second derivative (78.57%) and the third derivative (75.00%). With derivative and smoothing, the accuracy rate of the second derivative + smoothing (98.21%) and the third derivative + smoothing (98.21%) were better than the first derivative + smoothing (97.50%). Accuracy rate of the prediction model was not improved with just smoothing, and the derivative pretreatment improved accuracy. Also, with optimum parameters, there were no major differences between S-G derivative smoothing (98.42%) and the Norris derivative filter (98.57%). Thus, this study provided a new method and idea for rapid identification of wood species.