umu.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Bottom-up responses of the lower oceanic food web are sensitive to copepod mortality and feeding behavior
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Univ Munich, Dept Biol 2, Planegg Martinsried, Germany.
2015 (engelsk)Inngår i: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 60, nr 2, s. 641-656Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The functional response, describing consumption rate as a function of food abundance, critically links consumer-resource dynamics. Yet, little is known about how its shape affects communities of multiple, dynamically linked species. We theoretically investigated how the functional response of copepods (saturating type 2 vs. sigmoidal type 3, both of which have been observed) mediates bottom-up and top-down influences on the lower oceanic food web as described by five compartments (pentagon web): a shared limiting nutrient, small and large algae, ciliates feeding on small algae, and copepods feeding on ciliates and large algae. We compare system dynamics in response to nutrient enrichment and copepod mortality, the latter being varied first directly and then indirectly through inclusion of planktivores (fish or jellyfish). Regardless of functional response type, when planktivores are absent, equilibrium densities of all members of the even food chain (nutrients-small algae-ciliates-copepods) typically increase with nutrient enrichment whereas large algae decrease. In contrast, and congruent with conventional wisdom, large algae increase with nutrient enrichment when copepods are controlled by planktivores. A type 2 response in copepods strongly destabilizes the pentagon web, whereas stable equilibria are possible when copepods have a type 3 response. High copepod mortality (e.g., caused by increasing planktivore pressure under nutrient enrichment) destabilizes such systems, however. Moreover, because community feedbacks produce a negative correlation between the copepod's alternative prey, type 3 switching behavior is amplified in the pentagon web. This prevents extinctions but can give rise to an alternative state with small algal dominance at high enrichment.

sted, utgiver, år, opplag, sider
2015. Vol. 60, nr 2, s. 641-656
HSV kategori
Identifikatorer
URN: urn:nbn:se:umu:diva-102235DOI: 10.1002/lno.10044ISI: 000351126500022OAI: oai:DiVA.org:umu-102235DiVA, id: diva2:809332
Tilgjengelig fra: 2015-05-02 Laget: 2015-04-22 Sist oppdatert: 2018-06-07bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekst

Personposter BETA

Diehl, Sebastian

Søk i DiVA

Av forfatter/redaktør
Diehl, Sebastian
Av organisasjonen
I samme tidsskrift
Limnology and Oceanography

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 769 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf