This research proposal is an integral component of the international North Water (NOW) polynya project, a Canadian led effort to characterize the open-water ecosystem in the northern portion of ice-covered Baffin Bay. The region is of significant geopolitical interest due to commercial fisheries, shipping access to the Arctic, and to the native Inuit people who depend upon the extraordinary biological production in the NOW for their livelihood. Of parallel scientific interest is the fate of pelagic primary production exported from the system: i.e., whether sinking particulate materials remain available to support higher trophic levels or are recycled microbially at depth. This research is designed to test the hypothesis that cold temperature limits midwater microbial activities; it also examines specific enzymatic responses as predictive indicators of the autotrophic versus heterotrophic nature of the overlying ecosystem, within the context of the flow field. The PIs will test these and other questions by deploying a combination of particle sensors and collectors throughout NOW in the summers of 1997 and 19998. These will include long-term sediment traps secured to current-meter moorings, transmissometry measurements, in situ camera assessments of large-particles, and shipboard settling-column collections.
