I have studied various aspects of biological oceanographic processes for over 20 years. During this period, my research interests have evolved and expanded and range from studies on the nutrient metabolism, photoadaptations of photosynthesis, carbon metabolism and cell division of phytoplankton from natural populations in temperate and tropical oceans and in Antarctica to the relationships among primary producers and procaryotic and eukaryotic microheterotrophs, and the regulation of growth and loss processes of bacteria in various cold ocean regions. As part of my individual Research Grant program and a number of large collaborative projects (Canadian Joint Global Ocean Flux Study and International North Water Polynya Program) I have studied these processes in Newfoundland coastal waters, in the Gulf of St. Lawrence, the northeast subarctic Pacific and several sites in the high Arctic. My research is highly interdisciplinary and focuses on addressing large scale questions concerning the transformation of organic matter in the sea, biogeochemical cycling of biogenic carbon and the role of microbial trophic pathways in regulating the biological pump in the World Oceans. My current research activities are described in more detail on the following link.