NATO TU Black Sea Project Ecosystem Jodeling as a Management Tool for the Black Sea, ZORI ROSSII, Ukrayna, 15 - 19 Haziran 1997, cilt.47, ss.263-280, (Tam Metin Bildiri)
Some biochemical indices were applied in order to understand the state of food provision (or supply) for Black Sea pelagic animals during May 1991 and September 1996. Total lipid content and the main lipid fractions (especially wax esters) of Calanus euxinus females strongly correlated (P<0.005) with mean integrated chlorophyll-a of the euphotic zone. In September 1996 a trend (albeit not statistically high, r=0.79, P<0.1) was also observed between total lipid content of female Calanus and glycogen content of its predator, the ctenophore Pleurobrachia rhodopis. Comparison of sea regions differing in water dynamics for the biochemical indices used was of special interest. Animals from the cyclonic regions (where the main pycnocline is located at 100-120 m) contained almost double the lipid and glycogen content than those obtained from the anticylonic regions (where the main pycnocline is located at 160-190 m). The euphotic zone of cyclonic regions was also richer in nutrients (phosphate and nitrate) and chlorophyll (indicating phytoplankton biomass and thereby the food of Calanus) compared to anticyclonic regions. Long-term observations on the abundance and lipid content of the sprat Sprattus sprattus revealed the importance of river inflow for the nutrition of this pelagic fish species. As a result of the increased transport of riverborne nutrients, the lipid content of this fish had risen from 9% to 16%. It can be concluded: that these biochemical indices may be successfully used for monitoring the condition (well being) of dominant heterotrophic species in the pelagic ecosystem of the Black Sea.