木材の周期構造解析 III : 針葉樹横断面における仮道管の2次元的配置の評価

Abstract

針葉樹横断面における仮道管の2次元的配置の状態について検討するため, 接線方向の仮道管単列という概念を導入した。その結果, 早材部の仮道管配置は, このような接線方向の仮道管単列を放射方向にほぼ一定の周期で並べたものとしてとらえ得ることを示した。また, この接線方向の仮道管単列の定量的解析法を導入した。そして, その手法を用いた早材部と晩材部の仮道管配置の比較検討により, 晩材部では早材部の仮道管配置が放射方向にそのまま圧縮されたものであると考えられることを示した。

Two-dimensional arrangements of softwood tracheids on transverse section were evaluated by FFT and also some mathematical methods, being simplified on the 'dot maps' (Fig.1). In order to extract a basic cell arrangement from original complicated and two-dimentional one, a concept of 'tangental cellular unit' was introduced and offered to actual analyses (Fig.2). Mathematical methods became possible to be adopted on the 'tangentaial cellular unit', although it had still two-dimentional informations in itself. And also it was proved that the origenal tracheid arrangement over both early wood and late wood could be expressed by the periodical arrangement of such tangential cellular units along the radial direction. That is, tracheid arrangements could be analyzed mathematically and statistically by only two factors, the tangential cellular unit and change of radial diameter of tracheids.