Kipphut, G. W. Murray State University, george.kipphut@murraystate.edu
White, D. W. Murray State University, david.white@murraystate.edu
Kind, T. C. Murray State University, tckind@bach.mursuky.edu
Hendricks, S. P. Murray State University, susan.hendricks@murraystate.edu
White, S. B. Murray State University, steve.white@murraystate.edu

 
TRANSPORT AND UTILIZATION OF ORGANIC CARBON IN A LARGE RESERVOIR
 
We have been investigating biogeochemical processes affecting the cycling of carbon in Kentucky Lake, the largest reservoir within the Tennessee River Valley. Among the goals of the project are: 1) determination of organic carbon and total sediment accumulation rates; 2) determination of rates of chemical transformations that affect carbon accumulation; metabolism, and mineralization; and 3) determination of rates of sediment-biotic interactions which affect, and in turn are regulated by, fluxes of organic carbon. Since impoundment in 1944, we estimate that sedimentation has resulted in accumulation of 7.5 million tons of carbon and 750 million tons of total sediment within the lower 60 km of Kentucky Lake. Despite the high rates of sediment accumulation, the concentrations of sedimentary carbon and nitrogen are quite low. As a result, the macrobenthic fauna is poorly developed in most locations and is dominated by surface gatherers (chironomids) and surface suspension feeders (pelecypods), rather than by deposit feeders (oligochaetes). Water column primary productions rates are large during summer months (1200 mg C/m^2/day). However, most of this production is apparently transported out of the reservoir or remineralized near the sediment-water interface with little net accumulation in the sediments. Measured rates of bacterial production and nutrient and dissolved gases fluxes are quite high within the sediments and appear to be related to water temperature.
 
Day: Tuesday, Feb. 2
Time: 09:30 - 09:45am
Location: Sweeney Center
 
Code: SS19TU0930S