Molecular evidence for rapid dissolved organic matter turnover in Arctic fjords

From these findings we conclude that DOM produced during the spring/summer bloom is rapidly transformed within the short, but productive warm season by the specialized resident microbial community. Thus, in fall the DOM pool mainly consists of semi-refractory and refractory material, most of which has been introduced from Arctic Ocean water inflow. Assuming that our findings are representative for high latitude marine systems in general, the contribution of autochthonous seasonal DOC production in plankton bloom situations to the DOC pool in regions of deep water formation might be marginal.