Nonlinear multivariate time series (NLMVTS) analysis of whole tree fibre dimensions in E. globulus

摘要

Prediction equations confirm a significant and predominant Oblique I directionality following attained height (AH) lines from pith to bark and up the stem in 1 E. globulus tree (G3). The differential change in fibre morphology (with cambial age (CA~1) or ring (YR)) along these Oblique I axes is consistent between AHs (YR~*AH, P > 0.2). Within-ring changes in fibre length (FL), fibre coarseness (CR) and fibre diameter follow varying CA up the stem in G3; but this pattern of change varies significantly between rings (CA~*YR, 0.005 < P < 0.05). The within-ring longitudinal variation (Oblique axis II) of FL, CR, fibre diameter, lumen diameter and wall thickness, when referenced to height (HT) or AH, is consistent between years in G3 (YR~* HT, P > 0.5). Within-ring variation in FL, shows a significantly flatter decline when referenced to AH compared to HT. Seasonal earlywood (EW) to latewood (LW) growth affects within-ring variation of FL (P < 0.0005); with this EW to LW variation consistent between rings (and heights). FL is the only fibre dimension where this seasonal effect is a significant predictor of whole tree variation. Variation up the stem, at a given number of rings from the pith, shows predominantly a significant, non-cylindrical symmetry; whose pattern changes as the number of rings from the pith (CA) changes (CA~*HT, CA~*AH; 0.005