Re-eveluation of the self-thinning rule based on the law of the constancy of living cells

对过度拥挤的杉木和柏木林分的树干表面积与林分密度的关系进行了分析。结果表明，平均树干表面积与林分密度的倒数成正比，不受地域和树种的影响。这意味着单位林分面积的总树干表面积成为一个常数，与林分密度无关。这一面积保存规律被称为树干表面积恒定规律，对于树种来说，树干内部由死细胞组成，而活细胞则分布在树干表面以下。因此，干细胞表面积被认为与活细胞的数量成正比。这表明活细胞的恒定定律是成立的。

The relationship between stem surface area and stand density was analyzed for over-crowded Japanese cedar and Japanese cypress stands. The result indicated that the mean stem surface area was proportional to the reciprocal of the stand density independent of district and species. This means that the total stem surface area per unit stand area became a constant independent of the stand density. The area preservation rule was named the law f the constancy of stem surface area.For tree species, the inner portion of stem is composed of dead cells, whereas the living cells are distributed just below the stem surface. For this reason, the stem surface area is considered to be proportional to the amount of living cells. This suggested that the law of the constancy of living cells hold.