title: Trophic and individual efficiencies of size-structured communities.
abstract: Individual and trophic efficiencies of size-structured communities are derived from mechanistically based principles at the individual level. The derivations are relevant for communities with a size-based trophic structure, i.e. where trophic level is strongly correlated with individual size as in many aquatic systems. The derivations are used to link Lindeman's trophic theory and trophic theory based on average individuals with explicit individual-level size spectrum theory. The trophic efficiency based on the transfer of mass between trophic levels through predator-prey interactions is demonstrated to be valid only when somatic growth can be ignored. Taking somatic growth into account yields an average individual growth efficiency that is smaller than the trophic efficiency.
authors.affiliation: National Institute of Aquatic Resources (AQUA), Technical University of Denmark (DTU), Charlottenlund Slot, Jaegersborg Allé 1, 2920 Charlottenlund, Denmark. kha@aqua.dtu.dk
authors.forename: K H
authors.initials: KH
authors.lastname: Andersen
authors.forename: J E
authors.initials: JE
authors.lastname: Beyer
authors.forename: P
authors.initials: P
authors.lastname: Lundberg
mesh_terms: D000818:Animals; D049628:Body Size; D020387:Food Chain; D048788:Growth and Development; D008962:Models, Theoretical; D011156:Population Density; D011157:Population Dynamics
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