2003/2004

Food-Webs, Stoichometry, and Population Dynamics

Natural Sciences

Principal investigators

Dag Olav Hessen

Professor
University of Oslo (UiO)
Year at CAS

Abstract

Analysis of elemental ratios (stoichiometry) in food webs may provide fundamental information on the uptake, allocation and sequestration of carbon (C) and key nutrient minerals like phosphorus (P) and nitrogen (N) from the cellular level to ecosystems. In sum, these processes will also play a major role for the global cycling of these elements. The relative abundance of key nutrient minerals like phosphorus (P) and nitrogen (N) is not only instrumental to primary production, also secondary production (grazers) may be directly limited by the relative abundance of P and N. And when C:N or C:P ratios are high in primary producers, an increasing share of C will be in excess, relative to the grazers’ demands. This will have implications not only for energy transfer in food webs, but also community composition and system stability. It will also be a major determinant of CO2-uptake at the base of the food-web to yield at the top.

The project has consisted of 22 scientists who have analyzed these aspects in cells and ecosystems, covering topics from the role of P for cellular RNA and growth rate to large-scale ecosystem analysis and models. The work has addressed from three points of departure: continued work with existing data, projects and publication, analysis of large datasets from various databases and theoretical works and models.

Fellows

Tom Andersen

Associate Professor
University of Oslo (UiO)
Year at CAS

Thomas Robb Anderson

Dr.
Southampton Oceanography Centre
Year at CAS

Maarten Boersma

Privat Dozent
Alfred Wegener Institute for Polar and Marine Research, Helgoland
Year at CAS
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Francois Darchambeau

Dr.
University of Namur
Year at CAS

James Joseph Elser

Professor
Arizona State University
Year at CAS

Bjørn Faafeng

Head of Information
The Norwegian Institute for Water Research (NIVA)
Year at CAS

Per Johan Færøvig

Cand. Scient
University of Oslo (UiO)
Year at CAS

Erik Jeppesen

Professor
Aarhus University
Year at CAS

Sebastiaan (Bas) Adriaan Louis Maria Kooijman

Professor
Vrije Universiteit
Year at CAS

David Mayntz

Research Fellow
University of Oxford
Year at CAS

Edward McCauley

Professor
University of Calgary
Year at CAS

Jannicke Moe

Dr.
The Norwegian Institute for Water Research (NIVA)
Year at CAS
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Robert Ptacnik

Dr.
The Norwegian Institute for Water Research (NIVA)
Year at CAS

David Raubenheimer

Lecturer
University of Auckland
Year at CAS
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Robert W. Sterner

Professor
University of Minnesota
Year at CAS

Dietmar Straile

Professor
University of Konstanz
Year at CAS

Jotaro Urabe

Professor
Tohoku University
Year at CAS

Ellen van Donk

Professor
Netherland Institute of Ecology
Year at CAS
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Tobias Vrede

Dr.
Lund University
Year at CAS
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Bjørn Walseng

Research Fellow
The Norwegian Institute for Nature Research (NINA)
Year at CAS
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Karen Helen Wiltshire

Privat Dozent
Alfred Wegener Institute for Polar and Marine Research, Helgoland
Year at CAS

News

As part of Forskningsdagene 2017, CAS Oslo invited six current and former research fellows to give a 12-minute talk about science and values. In his talk, biologist Dag O. Hessen presents a range of ways to look at the value of nature.

Events