Phytoplankton Development in a Water Body with High Trophic Load

Abstract— Fish farming with the use of artificial food has changed the physicochemical characteristics of the water body. These changes included an increase in water turbidity, nitrogen and phosphorus concentrations, and the amount of organic particulate matter along with a decrease in oxygen concentration. This affected the phyto- and zooplankton community. The phytoplankton included 120 taxonomic units. Alga biomass was relatively low with the predominance of euglena, green, and yellow-green algae. Dominating were large-size daphnia and rotifers. The size of Daphnia longispina has increased to 2 mm, and that of Asplanchna priodonta helvetica rotifers, to 1.5 mm.