Aquacosm Is Nutrient D eficiency the Reason for

1. Aquacosm Is NutrientDeficiency the Reason for QualityDecrease in Turbot Fry Over the Season? Jepsen, P. M.1*, Blanda, E.1, Jakobsen, H. H.2, Novac, A.3, Pedersen, A. T.4 & Hansen, B. W.1 1. Department of Environmental, Social, and Spatial Change, Roskilde University, 4000, Roskilde, Denmark 2. Department of Bioscience, Aarhus University, 4000 Roskilde, Denmark 3. Faculty of Biology, ”AlexandruIoanCuza” University of Iasi, 700507, Romania 4. Maximus A/S, 7755, Bedsted Thy, Denmark Background: A classical food chain was established, producing live feed for turbot larvae, in 3 replicate 280 m3open top mesocosm tanks in three successive production cycles throughout May to September 2011 in Denmark 56°N. Prod. cycle Prod. cycle Prod. cycle Survival Survival Survival Defects Defects Defects Copepodabundance Phytoplanktonbiomass Fish larvae characteristics Inorganicnutrients 1 18% 3.5% 2 2.4% 12% 4% 9.6% 3 Conclusion: Nutrient depletion controls the classical food chain and decreased the phyto- and zooplankton biomass, resulting in a reduced turbot larvae survival Ph.d. student Per M. Jepsen pmjepsen@ruc.dk Roskilde University Denmark This work was funded by IMPAQ grant (J. no. 10-093522) to Professor Benni W. Hansen, CommScie – POSDRU/89/1.5/S/63663 to Ph.D. Aliona Novac and Eliteforsk travel grant (J. no. 11-116388) to Ph.D. student Per M. Jepsen.