Littoral zone benthic algal flora of Karagol in Karagol-Sahara National Park (Şavşat, Artvin)

Benthic algal flora of Karagol Lake, its seasonal variation and physical and chemical factors of the lake water were investigated between October 2008 and September 2010.Total 169 taxa that belong to divisions Ochrophyta (58), Charophyta (41), Chlorophyta (33), Cyanobacteria (18), Euglenozoa (17) and Myzozoa (2) were identified. In the benthic flora of the Karagol Lake Scenedesmus acutus f. tetradesmiformis, S. setiferus, Gonatozygon kinahanii, Actinotaenium diplosporum var. americanum, Cosmarium pseudoexiguum, Staurastrum hantzschii, S. boreale var. quadriradiatum, Staurodesmus dejectus var. apiculatus, Cronbergia siamensis, Trachelomonas cervicula, T. hispida var. granulata, and T. superba were identified new record for Turkish freshwater algal flora. In the benthic flora of the lake Ochrophyta division in terms of both species richness and abundance was the most dominant division. In the benthic, Cyclotella ocellata was the most dominant species and Epithemia sorex, Encyonema minutum, Staurosira venter and S. construens were subdominant.Physical and chemical parameters in the the lake water, temperature and dissolved oxygen were the most important factor that determining seasonal distribution of the algae. Shannon-Weaver diversity index values calculated for epipelic algae had varied 1,375 ? 3,128 and its mean value was recorded as 2,188. Benthic algal composition of the lake and physical and chemical parameters of the lake water indicate that the lake is mesotrophic character.