PHYTOPLANKTON OF THE HRUSOV-RESERVOIR ON THE RIVER DANUBE

In order to assess the possible changes in the abundance of phytoplankton in the Hrusov Reservoir a predictive model of phytoplankton biomass was modified. The was model formerly developed for the Hrusov-Dunakiliti Reservoir on the River Danube. The original concept of model was later applied for the building up Hrusov Reservoir (variant C). The retention time, depth and optical properties of water, together with seasonal changes of temperature, illumination, and inflow concentration of phytoplankton were considered as the most important factors influencing the growth of algae in the reservoir. Diatoms are expected to dominate but the share of green coccal algae may increase, especially in the shallow parts of the reservoir with restricted water exchange. Our results of qualitative and quantitative phytoplankton analyses are in a rather good accordance with our prognoses. Both previous and present states of the phytoplankton development are the topics of a detailed comparison.