| 要旨トップ | 目次 | | 日本生態学会第60回全国大会 (2013年3月，静岡) 講演要旨 ESJ60 Abstract |

一般講演（ポスター発表） P1-020 (Poster presentation)

Using Weller’s allometric model, the self-thinning exponent α_{x} of a partial organ x in overcrowded *Kandelia obovata* stands in Okinawa, Japan, was studied over eight years. The self-thinning exponent *α*_{x} was calculated on the basis of the coefficients *θ*_{x} and *δ*_{x} obtained from the allometric relationships of mean tree height H(=g_{θX}.w^{θX}) and mean organ mass density d(=g_{δX}.w^{δx}) to mean organ mass w_{X}. The self-thinning exponent α_{x} was estimated to be 1.40 for stem, 1.53 for branch, 1.01 for leaf, and 1.40 for aboveground. The φ_{x}-value (φ_{X}=1-(θ_{X}+δ_{X})) was not significantly different from 2/3 for stem, branch, and aboveground, i.e., α_{x}=3/2. Thus the self-thinning exponents for stem, branch and aboveground are not different from 3/2. On the other hand, the φ_{x}-value was also not significantly different from 3/4 for stem and aboveground, i.e., α_{x}=4/3. Therefore, the self-thinning exponent for stem and aboveground is not significantly different from 4/3. The φ_{L}-value for leaf was not significantly different from 1.0. The self-thinning exponents of partial organs except leaf and branch of *K. obovata* followed both the geometric and the metabolic model.