Composition and Abundance of Phytoplankton in Boggy Freshwater Lake, Turkey: In Relation to Physical and Chemical Variables

Lake Çalı (41° 12' N, 43° 13' E, Kars, Turkey) is a small (171273 m2, 1 m depth), shallow and macrophyte-dominated semi-arid Mediterranean lake. Although it is called a Lake, in reality it is a small pond. The phytoplankton of Lake Çalı was studied from May to September 2010 at three sampling stations. Eighty-two phytoplankton taxa were determined, consisting of Cyanophyta (15), Chlorophyta (30), Euglenophyta (13), Bacillariophyta (19), Cryptophyta (2), Dinophyta (1) and Chrysophyta (2). Total phytoplankton density increased from May to August. The dominant phytoplankton group was Cyanophyta during the study period, followed by Bacillariophyta and Chlorophyta. Temparature, pH and dissolved oxygen range from 14.6 to 21.6 0C, 7.62 to 8.08, 5.96 to 7.46 mg/L, respectively. Chlorophyll a level ranged from 0.0035 to 0.0059 mg/L. On the other hand both phosphate and nitrogen levels tended to increase from May to July. The maximum and minimum densities of phytoplankton were 14034 org/mL (August) and 11885 org/mL (September), respectively, and this variable correleted significantly with temperature, pH, DO, SRP, TP, Cyanophyta, and Bacillariophyta.