Composition and Seasonal Changes of Phytoplankton in Lake Büyük Akgöl (Sakarya)

Phytoplankton composition and some water quality parameters of lake büyük akgöl from 4 sampling stations were investigated between may 2003 and april 2004. phytoplanktonic taxa in the sampling stations, their monthly composition and variations in abundance were studied. in algal flora of lake büyük akgöl, a total of 51 taxa, 15 taxa of ochrophyta,; 12 taxa of chlorophyta; 11 taxa of cyanophyta; 4 taxa of dinophyta; 9 taxa of euglenophyta were identified. in the lake, chrysosporum bergii (ostenfeld) e. zapomelová, o. skácelová, p. pumann, r. kopp & e. janecek, dolichospermum sigmoideum (nygaard) wacklin, l. hoffmann & komarek, dolichospermum spiroides (klebhan) wacklin, l. hoffmann & komarek and microcystis viridis ( a.br.) lemm. were determined as the most dominant taxa. from these taxa euglena rostrifera l.p. johson is record in büyük akgöl. average water temperature at the stations were measured as 16.5 and ph 7, shannon weaver diversity index 1.26 and average trophic value (c) 18.5 in the lake. lake büyük akgöl could be defined as hypertrophic according to phytoplankton composition and values of trophic levels.