The composition, density, and seasonal variations of the planktonic diatoms of Lake Kaz were studied using samples taken from the surface and m depths between May 2005 and April 2006. Some physical and chemical properties of the lake water were also determined. | Turk J Biol 31 (2007) 203-224 © TÜB‹TAK Planktonic Diatom (Bacillariophyta) Composition of Lake Kaz (Pazar, Tokat) Esra ZA‹M Department of Biology, Faculty of Arts and Science, Gaziosmanpafla University, Tokat - TURKEY Received: Abstract: The composition, density, and seasonal variations of the planktonic diatoms of Lake Kaz were studied using samples taken from the surface and m depths between May 2005 and April 2006. Some physical and chemical properties of the lake water were also determined. Planktonic algae communities were identified, with 143 belonging to Bacillariophyta. Aulocoseira granulata, Aulocoseira italica, Cocconeis placentula, Cocconeis placentula var. euglypta, Cyclotella meneghiniana, Navicula radiosa, and Synedra ulna from the Bacillariophtya were dominant. Seasonal variations in the planktonic flora were observed during that period. According to the chemical and physical analyses performed, the lake has low alkali soft water. The level of pollution is not very important, but if precautions are not taken the lake will become polluted, and, as a result, it will turn into a swamp. Key Words: Planktonic diatoms, Lake Kaz, seasonal variations Kaz Gölü (Pazar-Tokat) Planktonik Diyatom (Bacillariophyta) Kompozisyonu Özet: Bu çal›flmada, Kaz Gölü’nün planktonik diyatomelerinin kompozisyonu, yo¤unlu¤u ve mevsimsel de¤iflimleri yüzey ve 1 metre derinlikten al›nan örneklerde May›s 2005 ile Nisan 2006 tarihleri aras›nda incelenmifltir. Ayr›ca göl suyunun baz› fiziksel ve kimyasal parametreleri de ölçülmüfltür. Planktonik alg toplulu¤unda Bacillariophyta 143 taksonla temsil edilmifltir. Toplulukta Bacillariophyta’dan Aulocoseira granulata, Aulocoseira italica, Cocconeis placentula, Cocconeis placentula var. euglypta, Cyclotella meneghiniana, Navicula radiosa, Synedra ulna dominant olarak bulunmufltur. Florada mevsimlere göre de¤ifliklik gözlenmifltir. Yap›lan fiziksel ve kimyasal analizlerde gölün hafif alkali, yumuflak su özelli¤ine sahip oldu¤u,
