Wavelet Analysis of X-ray Density Function of Tree Ring Structure

Abstract

The annual ring density of cross-sections of Japanese cedar stems of different ages has been recorded by X-ray density analyser in order to determine the boundary line between juvenile and mature wood. A particular emphasis was put on the tracheid length in the annual rings. The obtained data was analysed by using Wavelet transformation. It can be assumed that the process of formation of woody tissue is a periodic one and that the characteristic periods include several annual rings. This also indicates that the growth of a tree can be separated into distinct processes that can be identified within the juvenile and mature wood zones. It has been shown that the suggested numerical approach enables a rapid and reliable evaluation of the data.

Keywords

• Juvenile/mature wood
• Hurst exponent
• tracheid length
• X-ray densitometry
• wavelet transform