2022-08-15T16:28:40Z https://u-ryukyu.repo.nii.ac.jp/oai
oai:u-ryukyu.repo.nii.ac.jp:02004813 2022-02-15T03:57:32Z 1642837622505:1642837957109:1642837972945 1642838403551:1642838406414
A Note on the Fundamental Equation of Self-Thinning in the Logistic Theory of Plant Growth Hagihara, Akio 萩原, 秋男 The fundamental equation of self-thinning, which was proposed in the logistic theory of\nplant growth for describing the density effect in self-thinning populations, is based on\nthe following two fundamental assumptions: one is that the growth of mean phytomass w\nfollows a general logistic equation; the other is that the final yield Y(t), which is pre\nscribed as the product of the asymptote of mean phytomass W(t) and density P , becomes\nconstant irrespective of P , i.e. the law of constant final yield is assumed. In the light\nof the basic principle of self-thinning that the relative growth rate of mean phytomass\n(l/u>) (dw/dt) is given by the sum of the relative growth rate of yield (1/y) (dy/dt) and\nthe relative mortality (-1/P) (dP/dt), the first assumption brings to the conclusion that the\nfinal yield Y(t) is not prescribed by W{t) P , but is prescribed by(l-tn/A (t))W(t) P\n(ro, relative mortality; A (f), coefficient of growth), whose value depends on density P\nexcept for the special case where both Wit) P and m are independent of P. This inevitable\nconsequence is in conflict with the prescription referring to the final yield Y(t) in the\nsecond assumption of the logistic theory of plant growth. As a result, it is suggested\nthat an alternative theory for the density effect in self-thinning populations should be\nnewly constructed to harmonize the assumption referring to the growth of mean phytomass\nwith the assumption referring to the law of constant final yield. 紀要論文 http://purl.org/coar/resource_type/c_6501 琉球大学理学部 VoR http://hdl.handle.net/20.500.12000/11819 0286-9640 AN00250774 琉球大学理学部紀要 Bulletin of the College of Science. University of the Ryukyus 64 76 69 eng open access