Journal article
Size-based predictions of food web patterns
Department of Applied Mathematics and Computer Science, Technical University of Denmark1
National Institute of Aquatic Resources, Technical University of Denmark2
Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark3
Scientific Computing, Department of Applied Mathematics and Computer Science, Technical University of Denmark4
Section for Marine Ecology and Oceanography, National Institute of Aquatic Resources, Technical University of Denmark5
We employ size-based theoretical arguments to derive simple analytic predictions of ecological patterns and properties of natural communities: size-spectrum exponent, maximum trophic level, and susceptibility to invasive species. The predictions are brought about by assuming that an infinite number of species are continuously distributed on a size-trait axis.
It is, however, an open question whether such predictions are valid for a food web with a finite number of species embedded in a network structure. We address this question by comparing the size-based predictions to results from dynamic food web simulations with varying species richness. To this end, we develop a new size- and trait-based food web model that can be simplified into an analytically solvable size-based model.
We confirm existing solutions for the size distribution and derive novel predictions for maximum trophic level and invasion resistance. Our results show that the predicted size-spectrum exponent is borne out in the simulated food webs even with few species, albeit with a systematic bias. The predicted maximum trophic level turns out to be an upper limit since simulated food webs may have a lower number of trophic levels, especially for low species richness, due to structural constraints.
The size-based model possesses an evolutionary stable state and is therefore un-invadable. In contrast, the food web simulations show that all communities, irrespective of number of species, are equally open to invasions. We use these results to discuss the validity of size-based predictions in the light of the structural constraints imposed by food webs
Language: | English |
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Publisher: | Springer Netherlands |
Year: | 2014 |
Pages: | 23-33 |
ISSN: | 18741746 and 18741738 |
Types: | Journal article |
DOI: | 10.1007/s12080-013-0193-5 |
ORCIDs: | Knudsen, Kim and Andersen, Ken Haste |