Akio Inoue;Miyuki Shimada;Motohiro Sato;Hiroyuki Shim

Faculty of Environmental and Symbiotic Sciences Prefectural University of Kumamoto Kumamoto Japan;Faculty of Engineering Hokkaido University Sapporo Japan;Department of Environmental Sciences, University of Yamanashi, Kofu, Japan

Apparent culm volume;Carbon sequestration;Genus Phyllostachys;Hollow cylindrical culm;Woody culm volume;CARBON STORAGE;COFFEE REGION;BIOMAS

The hollow cylindrical culm is one of the most remarkable morphological characters of most bamboo species. In relation to its hollow structure, there are two different attributes of the culm volume in bamboo: the apparent culm volume (v(a): the total culm volume including the hollow portion) and the woody culm volume (v(w): the volume of the woody walls of the culm). The ratio of v(w) to v(a) is defined as the reduction factor for culm volume (f(v)). The quantity f(v) is useful to quantify the biomass resources of bamboo culms as well as to evaluate the carbon stock of bamboo forests. However, the direct measurement of f(v) requires destructive sampling, which consumes time and labor. Hence, an alternative method for obtaining f(v) is desired. In this study, we examined f(v) in five species of the genus Phyllostachys and proposed alternative methods to estimate f(v). Our data showed that f(v) varied by species, some of which exhibited a dependency of f(v) on culm sizes. These findings indicate that the intraspecific and interspecific variation in f(v) should be considered carefully when converting v(a) into v(w) by f(v). Based on our results, we propose here six approaches for predicting f(v) and we discuss their advantages and disadvantages. Our results are intended to facilitate evaluation of the carbon sequestration capacity of bamboo forests and the commercial utilization of bamboo culms.