Three allometric relations of population density to body mass: theoretical integration and empirical tests in 149 food webs.
Predicting species population density-body mass scaling in community food webs (henceforth webs) is important for conservation and to understand community structure. Very different types of scaling have been studied, based on either individuals or species. The individual size distribution (ISD) describes the distribution of individual-organism body masses regardless of taxonomy, and contains the same information as the abundance spectrum. Focusing instead on species, the local size-density relationship (LSDR) plots population densities vs. mean body masses of species. The distribution of species mean body masses (the species-mean-size distribution, SMSD) is also important but previously little studied in webs. We here combine and formalize theory of several authors to predict: how these three descriptions are related; the forms of the LSDR and ISD; and variation in scaling among webs. We describe empirically the SMSDs of two pelagic, one estuarine, and 146 soil webs by power laws and generalizations. We test theory and find it broadly validated.
Reuman
Daniel C
DC
Laboratory of Populations, Rockefeller University, 1230 York Avenue, Box 20, New York, NY 10065, USADepartment of Ecology, RIVM, 9 Antonie van Leeuwenhoeklaan, Box 1, Bilthoven 3720 BA, The NetherlandsEnvironment Department, University of York, York YO10 5DD, UK.
Mulder
Christian
C
Laboratory of Populations, Rockefeller University, 1230 York Avenue, Box 20, New York, NY 10065, USADepartment of Ecology, RIVM, 9 Antonie van Leeuwenhoeklaan, Box 1, Bilthoven 3720 BA, The NetherlandsEnvironment Department, University of York, York YO10 5DD, UK.
Raffaelli
Dave
D
Laboratory of Populations, Rockefeller University, 1230 York Avenue, Box 20, New York, NY 10065, USADepartment of Ecology, RIVM, 9 Antonie van Leeuwenhoeklaan, Box 1, Bilthoven 3720 BA, The NetherlandsEnvironment Department, University of York, York YO10 5DD, UK.
Cohen
Joel E
JE
Laboratory of Populations, Rockefeller University, 1230 York Avenue, Box 20, New York, NY 10065, USADepartment of Ecology, RIVM, 9 Antonie van Leeuwenhoeklaan, Box 1, Bilthoven 3720 BA, The NetherlandsEnvironment Department, University of York, York YO10 5DD, UK.
D000818:Animals; D049628:Body Size / Q000502:physiology*; D017753:Ecosystem; D020387:Food Chain; D008954:Models, Biological; D011156:Population Density