Derivation of two-way volume equation for bamboo, Phyllostachys pubescens

作者：Suga Hideo; Inoue Akio^*; Kitahara Fumiaki

来源：Journal of Forest Research, 2011, 16(4): 261-267.

DOI：10.1007/s10310-010-0223-8

• Apparent culm volume
• Bamboo
• Normal form-factor
• Phyllostachys pubescens
• Volume equation

We derive a two-way volume equation for estimating the apparent culm volume of one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. The volume equation was derived from the assumptions that (1) the relative culm form can be expressed by Kunze's equation and (2) normal form-factors at two different relative heights are steady at constants independent of culm sizes. A total number of 200 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan, and were randomly bisected into two sets of data, i.e. modeling and test data. For the modeling data, normal form-factors at 0.6 and 0.9 in relative height were steady at 0.908 and 0.448, respectively. The coefficients of the volume equation were determined based on these steady values of the normal form-factors. For the test data, the apparent culm volume was estimated from diameter at breast height and culm height with the determined volume equation. The mean error and root mean square error of the estimated culm volume were, respectively, 8.120 x 10(-5) and 3.291 x 10(-3) m(3), and there was no significant difference between estimated and actual volume. In conclusion, the two-way volume equation presented here appears to be convenient for predicting the apparent culm volume for P. pubescens.

• 出版日期2011-8