SEASONAL FLUCTUATION IN THE DIVERSITY OF MACROPHYTES AND THEIR ABUNDANCE IN LAKE PRESPA

In the littoral region of Lake Prespa there are distributed different populations of macrophyte vegetation in zones (belts). The qualitative composition and abundance of macrophyte vegetation are one of the most relevant indicators for the quality of water ecosystem. This group of organisms is characterized by a wide range of environmental tolerances and preferences that characterize indicators of water quality over a long period of time. The sampling of macrophytes was conducted in 4 seasons (spring, summer, autumn and winter) in 2023, in 7 different localities in the Lake (Oteshevo, Stenje, Ezerani, Asamati, Krani, Konjsko, and Nakolec). The results showed that a total of 10 macrophyte species were recorded during the research, with different densities at different depths and seasons. The density of macrophytes is highest at a depth of 2 m, during the summer period. The increased anthropogenic influence and nutrient load, as well as changes in the climate generally caused the seasonal fluctuation and the changes in the diversity and the biomass in all macrophyte species.