The Algae and their seasonal variations in Gülüşkür region of Keban Dam Lake

II ABSTRACT PhD Thesis THE ALGAE AND THEIR SEASONAL VARIATIONS IN GÜLÜŞKÜR REGION OF KEBAN DAM LAKE Güneş (TOPRAK) PALA Fırat University Graduate School of Natural and Applied Sciences Department of Aquaculture 2001, Page: 107 In this study, algae and water samples taken from three stations in Gülüşkür region and two stations in Yolüstü region were investigated between September 1996 and September 1998. During this study, a total of 334 algal taxa belonging to Bacillariophyta (182 ), Chlorophyta (97), Cyanophyta (50), Dinophyta (1), Euglenophyta (2) and Xanthophyta (2) were determined respectively. Diatoms (Bacillariophyta) were the most significant algae both with respect to invidual numbers and frequency of occurrence followed by Chlorophyta and Cyanophyta. Diatom genera Nitzschia, Navicula, Achnanthes and Cymbella; Green algal genera Scenedesmus, Pediastrum and Tetraedron; Blue-Green genera, Anabaena and Oscillatoria were the most conspicuous members of the Phytoplankton of Gülüşkür region of Keban Dam Lake. Although diatoms occurred in all seasons their highest numbers were encountered in spring and autumn whilst green and blue-green algae were generally more conspicuous in spring and summer. Key Words: Phytoplankton, Keban Dam Lake, Elazığ.