Panzenböck, M. University of Vienna, Austria, email@example.com
CARBON FLUX FROM PHYTO- TO BACTERIOPLANKTON IN A HIGH ARCTIC LAKE ON FRANZ-JOSEPH-LAND
Dynamics of autotrophic and heterotrophic communities with focus on primary and bacterial production were followed in a high arctic lake on Franz-Joseph-Land (80 to 82 N, 45 to 65 E) in July and August 1996. The investigated lake is ultraoligotrophic, permanently ice-covered (~10% ice-free in summer)and maximum water temperature is 2 C. Phytoplankton biomass and primary production decreased during the investigation period. At the end of the algal bloom the photosynthetical extracellular release (Per) predominated over the particulate production. The extracellular carbon corrected for bacterial uptake amounted to 30-96% of carbon fixation. Temporal dynamics of bacterioplankton production covariated with percentage of Per indicating that Per is the major carbon source for bacteria. About 31% of Per and 19% of totally primary production, respectively, was used for bacterial growth. Transport of algal carbon to rotifers was of similar magnitude whereas flagellates metabolism seemed to be negligible for carbon pathways in this arctic lake.
Day: Tuesday, Feb. 2
Location: Sweeney Center