Consumption patterns, complexity and enrichment in aquatic food chains
Författare
Summary, in English
The interactions between consumers and prey, and their impact on biomass distribution among trophic levels, are central issues in both empirical and theoretical ecology. In a long-term experiment, where all organisms, including the top predator, were allowed to respond to environmental conditions by reproduction, we tested predictions from `prey-dependent' and `ratio-dependent' models. Prey-dependent
models made correct predictions only in the presence of strong interactors in simple food chains, but failed to predict patterns in more complex situations. Processes such as omnivory, consumer excretion, and unsuitable prey-size windows (invulnerable prey) increased the complexity and created patterns resembling ratio-dependent consumption. However, whereas the prey-dependent patterns were created by the mechanisms predicted by the model, ratio-dependent patterns were not, suggesting that they may be right for the wrong reason'. We show here that despite the enormous complexity of ecosystems, it is possible to identify and disentangle mechanisms responsible for observed patterns in community structure, as well as in biomass development of organisms ranging in size from bacteria to fish.
models made correct predictions only in the presence of strong interactors in simple food chains, but failed to predict patterns in more complex situations. Processes such as omnivory, consumer excretion, and unsuitable prey-size windows (invulnerable prey) increased the complexity and created patterns resembling ratio-dependent consumption. However, whereas the prey-dependent patterns were created by the mechanisms predicted by the model, ratio-dependent patterns were not, suggesting that they may be right for the wrong reason'. We show here that despite the enormous complexity of ecosystems, it is possible to identify and disentangle mechanisms responsible for observed patterns in community structure, as well as in biomass development of organisms ranging in size from bacteria to fish.
Avdelning/ar
Publiceringsår
1998
Språk
Engelska
Sidor
901-906
Publikation/Tidskrift/Serie
Royal Society of London. Proceedings B. Biological Sciences
Volym
265
Issue
1399
Dokumenttyp
Artikel i tidskrift
Förlag
Royal Society Publishing
Ämne
- Ecology
Nyckelord
- food chain
- ratio-dependent
- prey-dependent
- enrichment
- omnivory
Status
Published
Forskningsgrupp
- Biodiversity and Conservation Science
- Aquatic Ecology
- Theoretical Population Ecology and Evolution Group
ISBN/ISSN/Övrigt
- ISSN: 1471-2954