title: Mixed-power scaling of whole-plant respiration from seedlings to giant trees.
abstract: The scaling of respiratory metabolism with body mass is one of the most pervasive phenomena in biology. Using a single allometric equation to characterize empirical scaling relationships and to evaluate alternative hypotheses about mechanisms has been controversial. We developed a method to directly measure respiration of 271 whole plants, spanning nine orders of magnitude in body mass, from small seedlings to large trees, and from tropical to boreal ecosystems. Our measurements include the roots, which have often been ignored. Rather than a single power-law relationship, our data are fit by a biphasic, mixed-power function. The allometric exponent varies continuously from 1 in the smallest plants to 3/4 in larger saplings and trees. Therefore, our findings support the recent findings of Reich et al. [Reich PB, Tjoelker MG, Machado JL, Oleksyn J (2006) Universal scaling of respiratory metabolism, size, and nitrogen in plants. Nature 439:457-461] and West, Brown, and Enquist [West GB, Brown JH, Enquist BJ (1997) A general model for the origin of allometric scaling laws in biology. Science 276:122 -126.]. The transition from linear to 3/4-power scaling may indicate fundamental physical and physiological constraints on the allocation of plant biomass between photosynthetic and nonphotosynthetic organs over the course of ontogenetic plant growth.
authors.affiliation: Forestry and Forest Products Research Institute, Matsunosato 1, Tsukuba 305-8687, Japan. moris@ffpri.affrc.go.jp
authors.forename: Shigeta
authors.initials: S
authors.lastname: Mori
authors.forename: Keiko
authors.initials: K
authors.lastname: Yamaji
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ishida
authors.forename: Stanislav G
authors.initials: SG
authors.lastname: Prokushkin
authors.forename: Oxana V
authors.initials: OV
authors.lastname: Masyagina
authors.forename: Akio
authors.initials: A
authors.lastname: Hagihara
authors.forename: A T M Rafiqul
authors.initials: AT
authors.lastname: Hoque
authors.forename: Rempei
authors.initials: R
authors.lastname: Suwa
authors.forename: Akira
authors.initials: A
authors.lastname: Osawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nishizono
authors.forename: Tatsushiro
authors.initials: T
authors.lastname: Ueda
authors.forename: Masaru
authors.initials: M
authors.lastname: Kinjo
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Miyagi
authors.forename: Takuya
authors.initials: T
authors.lastname: Kajimoto
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Koike
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Matsuura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Toma
authors.forename: Olga A
authors.initials: OA
authors.lastname: Zyryanova
authors.forename: Anatoly P
authors.initials: AP
authors.lastname: Abaimov
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Awaya
authors.forename: Masatake G
authors.initials: MG
authors.lastname: Araki
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Kawasaki
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Chiba
authors.forename: Marjnah
authors.initials: M
authors.lastname: Umari
mesh_terms: D018533:Biomass; D001901:Botany / Q000379:methods*; D005740:Gases / Q000032:analysis* / Q000378:metabolism; D018526:Plant Transpiration; D036226:Seedlings / Q000737:chemistry* / Q000502:physiology; D014197:Trees / Q000737:chemistry* / Q000502:physiology
chemical_list: D005740:Gases