since 2015: Chair of the Consortium German Marine Research since 2013: Member in the Executive Board of the Leibniz Association and Chair of Section Environmental Sciences, Chair of the Leibniz Science Campus Phosphor Research, Rostock since 2011: Director of the Leibniz Institute for Baltic Research, Warnemünde (IOW), Professor in Earth System Sciences and Interdisciplinary Faculty - Maritime Systems - at the University of Rostock before 2011:  Scientist, Head of Department Polar Biological Oceanography, Head of Research Division Biosciences at the Alfred Wegner Institute for Marine and Polar research AWI, Professor in Biological Oceanography, University Bremen