Affiliation: | a Department of Earth and Environmental Science, University of Pennsylvania, 240 South 33rd Street, Philadelphia, PA 19104-6316, USA b Tanashi Experimental Station, University Forests, The University of Tokyo, Midori-cho 1-1-8, Nishitokyo-shi, Tokyo 188-0002, Japan c Arboricultural Research Institute, University Forests, The University of Tokyo, Kanou 457, Minami-Izu-Machi, Kamo-gun, Shizuoka 415-0304, Japan d Graduate School of Agriculture, Kyoto University Forests, Kyoto University, Kitashirakawa, Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan e Forest Resources Planning, Ehime University, 3-5-7 Tarumi, Matsuyama, Japan |
Abstract: | We quantified structural features and the aboveground biomass of the deciduous conifer, Metasequoia glyptostroboides (Hu and Cheng) in six plantations in central Japan. In order to derive biomass estimates we dissected 14 M. glyptostroboides trees into three structural components (stem wood, branch wood and foliage) to develop allometric equations relating the mass of these components and of the whole tree to diameter at breast height (DBH). We found robust relationships at the branch and whole tree level that allow accurate prediction of component and whole tree biomass. Dominant tree height was similar within five older (>40 years) plantations (27–33 m) and shorter in a 20-year-old plantation (18 m). Average stem diameter varied from 12.8 cm in the youngest stand to greater than 35 cm in the oldest stand. Metasequoia have relatively compact crowns distributed over the top 30% of the tree although the youngest stand had the deepest crown relative to tree height (up to 38%). At the individual tree level in older stands, 87% of the aboveground biomass was allocated to the stem, 9% to branch wood and 4% to foliage. We found little difference in the relative distribution of above ground biomass among the stands with the exception of lower foliage biomass in larger diameter trees. Total aboveground biomass of the older stands varied twofold, ranging from a maximum of 450 Mg ha−1 in a 42-year-old stand to a minimum of 196 Mg ha−1 in a 48-year-old stand. Total above ground biomass of the 20-year-old stand was 176 Mg ha−1. |