Poster Details
THE CONTRIBUTION OF DARK METABOLISM TO STREAM ECOSYSTEM ENERGETICS
The flow of carbon and nutrients through streams is fundamentally linked to the flow of energy. Dark metabolism – the collection of anaerobic respiration and metabolic processes not mediated by light – can constitute a significant portion of the net energy flow. Traditional measurements of stream metabolism calculate rates of net ecosystem productivity based on diel O2 curves, using the assumption that photosynthesis and aerobic respiration are the only processes acting to produce or consume energy. This does not capture dark metabolism, which has been measured and found to contribute substantially to net energy flow in a variety of streams. Dark metabolism includes both autotrophic processes (e.g. nitrification) and heterotrophic processes (e.g. denitrification), with these processes constituting up to 13% and 19% of the energetic budgets respectively. In this study we present a synthesis of stream energy budgets calculated from Gibbs free energy of the processes measured in available literature.
Alice M. Carter (Primary Presenter/Author), Flathead Lake Biological Station, University of Montana, alicecarter05@gmail.com;
Emily Bernhardt ( Co-Presenter/Co-Author), Duke University, ebernhar@duke.edu;
Jim Heffernan ( Co-Presenter/Co-Author), Duke University, james.heffernan@duke.edu;