Peter Tiselius, University of Gothenburg, Sweden talks on "Controlling factors for the primary production in a coastal ecosystem-results from a 28-year time series in the Gullmar Fjord, west coast of Sweden" in the so-called Kaffeklubben at DTU Aqua. Kaffeklubben arranges seminars presenting recent research within aquatic sciences. Guests are welcome.
Abstract
Coastal waters exposed to high levels of nutrients are generally considered to be typical bottom-up controlled ecosystems. The highly variable nature of the systems, however, tends to obscure the true controlling factors, and only long time series can teach us how they function. Using the worlds longest time series of in-situ primary production measurements, I will show that even the mesotrophic Gullmar Fjord, west coast of Sweden, shows signs of top-down control by zooplankton. Strong positive correlations between primary production and zooplankton biomass concurrent with strong negative correlations between primary production and phytoplankton biomass indicate trophic cascades and an ecosystem controlled by zooplankton carnivores. This has implications for the management of coastal waters and emphasize the importance of regulating the fishery of certain size classes of fish for a good environmental status.
About Kaffeklubben
DTU Aqua’s so-called Kaffeklubben (The Coffee Club) arranges seminars presenting recent research on various topics across aquatic sciences, hence contribution to knowledge sharing in DTU Aqua.
The lectures are held by scientists from DTU Aqua or from other research institutes in Denmark or abroad. The audience consists mainly of employees at DTU Aqua, but others are welcome to participate. Registration is not necessary
The seminars are in English and last one hour. They take place at DTU Aqua in Charlottenlund, Copenhagen.