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No.66 (1998/9) >

 
Title :Mathematical and Biological Considerations on Yield- and Competition-Density Effects in Self-thinning Plant Populations
Authors :Hagihara, Akio
Authors alternative :萩原, 秋男
Issue Date :Sep-1998
Abstract :A mathematical model for describing the density effect occurring in self-thinning populations is developed on the basis of the following three basic assumptions: (1) the growth of yield follows the general logistic equation; (2) final yield becomes constant irrespective of initial density; and (3) there exists a functional relationship between actual and initial densities. The resultant equation takes the same reciprocal form as the reciprocal equation derived from Shinozaki-Kira's theory, i.e., the logistic theory of the C-D effect, which deals with the density effect occurring in nonself-thinning populations. It is, however, recognized that one of the two coefficients is quite different in mathematical interpretation between the two reciprocal equations based on the present theory and the logistic theory of the C-D effect, respectively. The present conclusion is consistent with the empirical facts that the reciprocal relationship between yield (or mean phytomass) and density is discernible in not only nonself-thinning populations, but also self-thinning populations. The present model is expected to systematically interpret underlying mechanisms be tween the density effect, which is observed at a time constant among populations varying in initial density, and self-thinning, which is observed along a time continuum in any given population.
Type Local :紀要論文
ISSN :0286-9640
Publisher :琉球大学理学部
URI :http://hdl.handle.net/20.500.12000/11817
Citation :琉球大学理学部紀要 = Bulletin of the College of Science. University of the Ryukyus no.66 p.71 -79
Appears in Collections:No.66 (1998/9)

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