A Consideration of the Constancy of Biomass Density in Plant Populations Undergoing Self-Thinning

The constancy of biomass density was considered in an entire plant population p by combining two adjacent populations p1 and p2 for which the self-thinning rule is assumed to be satisfied independently and each biomass density is also assumed to be the same constant value. Under these assumptions, the biomass density d in a population p was formulated as d=c((km−α+1)(km+1)/(km1−α+1)(k+1)), where c is biomass density of p1 and p2, and k and m are stand area and density ratio of p1 to p2, respectively, and α is the self-thinning slope. In the case of m≠1, the value of d in the above equation is always larger than unity. This fact indicates that the biomass density in a combined population p is not equal to the biomass density c in each population p1 or p2 because of systematic error