Dissertation Research: Identifying the Sources and Ages of Organic Matter Supporting Estuarine Bacterial Production: A Novel Multiple Isotope Approach

College Of William & Mary Virginia Institute Of Marine Science, Gloucester Point VA

Investigators

Abstract

00-73243 Ducklow/McCallister DDIG: Identifying the sources and ages of organic matter supporting estuarine bacterial production: A novel multiple isotope approach The effects of long-term changes in land use patterns are focused in the coastal zone. These changes have fundamentally altered both the magnitude and composition of riverine organic matter exported to the estuary. This, in turn, has the potential to shift the metabolic balance between production and respiration in the water column. This study will help to determine the role of bacteria in regulating estuarine metabolic balance by examining the size fractions, sources, and ages of estuarine dissolved organic matter (DOM) incorporated into bacterial biomass in the York River Estuary (a sub-estuary of the Chesapeake Bay). In addition, the PIs will experimentally investigate the fraction of DOM which can be metabolized on the time scale of estuarine residence times. The investigators will employ a novel approach, involving a multiple isotope, to overcome the traditional methodological limitations of research in this area.