A Study on the Phytoplankton of Hasan UĞURLU Dam Lake (Samsun-Turkey)

Abstract: The composition and seasonal variations of phytoplankton of Hasan UĞURLU Dam Lake were studied using samples collected from two stations between July 1992 to December 1993. 57 taxa were identified belonging to the Bacillariophyta, Chlorophyta, Cyanophyta, Dinophyta and Euglenophyta divisions of phytoplankton. In the phytoplankton, Asterionella formosa, Cyclotella planc-tonica, Pediastrum simplex and Ceratium hirundinella caused water blooms in certain months. The light density and temperature affected the composition and seasonal variations in phytoplankton considerably. Nutrient levels in the lake did not limit the seasonal variations in phytoplankton. It was determined that Lake Hasan Uğurlu had mesotrophic characteristics because of the morpho-metric structure, physical and chemical properties of the water and a phytoplankton type which caused water blooming by various taxa during certain month