3/2乗則系の統計学的基礎 : (植物群落における個体の重さ・直径・高さの頻度分布. VIII)
1985 年 35 巻 2 号 p. 169-182
詳細
1985 年 35 巻 2 号 p. 169-182
YAMAKURA, Takuo (Dept. Biol., Fac. Sci., Osaka City Univ., Osaka). 1985. Statistical basis for the 3/2 power law system (Frequency distribution of individual weight, stem diameter and height in plant stands. VIII). Jap. J. Ecol., 35 : 169-182. When the 3/2 power law of self-thinning holds in forest stands, some interesting relations are recognizable among basal area, mean stem diameter, mean tree height, and tree density in the stands. The relations of these variables, the 3/2 power law of self-thinning, and their derivatives were lumped together in a system designated as the 3/2 power law system. Adopting the results of the preceding last study, statistical models were proposed to explain the interrelationships of the component laws of the system. The fundamental construction of the models depended on Pearson's type VII distribution and upon allometric relations among stem diameter, tree height, and individual weight. To determine the form of each component law of the system, all the coefficients of Pearson's type VII distribution and allometric relations were expressed in empirical equations of tree density in a stand. Although the hypothesis of geometrical similarity in tree shape has been adopted for explaining the construction of the 3/2 power law system, the proposed new explanations for the system were free from the hypothesis.
