Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Consumption patterns, complexity and enrichment in aquatic food chains

Author:
  • Lars-Anders Hansson
  • Christer Brönmark
  • Per Nyström
  • Per Lundberg
  • Larry Greenberg
  • Anders Nilsson
  • Anders Persson
  • Lars Pettersson
  • Pia Romare
  • Lars J. Tranvik
Publishing year: 1998
Language: English
Pages: 901-906
Publication/Series: Royal Society of London. Proceedings B. Biological Sciences
Volume: 265
Issue: 1399
Document type: Journal article
Publisher: Royal Society

Abstract 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.

Keywords

  • Ecology
  • food chain
  • ratio-dependent
  • prey-dependent
  • enrichment
  • omnivory

Other

Published
  • ISSN: 1471-2954
Lars B. Pettersson
E-mail: lars.pettersson [at] biol.lu.se

Researcher

Biodiversity

+46 46 222 38 18

+46 70 611 63 45

E-B371

50

Centre for Animal Movement Research
Evolutionary Ecology, Department of Biology
Ecology building S-223 62 Lund Sweden