title: A New Model for Size-Dependent Tree Growth in Forests.
abstract: Tree growth, especially diameter growth of tree stems, is an important issue for understanding the productivity and dynamics of forest stands. Metabolic scaling theory predicted that the 2/3 power of stem diameter at a certain time is a linear function of the 2/3 power of the initial diameter and that the diameter growth rate scales to the 1/3 power of the initial diameter. We tested these predictions of the metabolic scaling theory for 11 Japanese secondary forests at various growth stages. The predictions were not supported by the data, especially in younger stands. Alternatively, we proposed a new theoretical model for stem diameter growth on the basis of six assumptions. All these assumptions were supported by the data. The model produced a nearly linear to curvilinear relationship between the 2/3 power of stem diameters at two different times. It also fitted well to the curvilinear relationship between diameter growth rate and the initial diameter. Our model fitted better than the metabolic scaling theory, suggesting the importance of asymmetric competition among trees, which has not been incorporated in the metabolic scaling theory.
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Higashi-Hiroshima city, Hiroshima, Japan.
authors.forename: Masae Iwamoto
authors.initials: MI
authors.lastname: Ishihara
authors.affiliation: Department of Life Science of Agriculture, Obihiro University of Agriculture and Veterinary Medicine, Obihiro city, Hokkaido, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Konno
authors.affiliation: Graduate School of Horticulture, Chiba University, Matsudo city, Chiba, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Umeki
authors.affiliation: Forestry Research Institute, Hokkaido Research Organization, Bibai city, Hokkaido, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Ohno
authors.affiliation: Zushioku Onoecho, Yamashina, Kyoto city, Kyoto, Japan.
authors.forename: Kihachiro
authors.initials: K
authors.lastname: Kikuzawa
mesh_terms: D000465:Algorithms; D018533:Biomass; D003198:Computer Simulation; D065928:Forests; D008954:Models, Biological; D018547:Plant Stems / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism; D014197:Trees / Q000033:anatomy & histology / Q000254:growth & development* / Q000378:metabolism