Phytoplankton composition and ecological characteristics of some lentic ecosystems in the Ceyhan Basin

Phytoplankton is one of the five biological quality components as ecological indicator recommended by the EU Water Framework Directive for the assessment of ecological status lentic ecosystems. The aim of the present study was determination of ecological status and ecological preferences of phytoplankton assemblages from the between July 2014 and August 2015, Lake Azaplı, Ayvalı Reservoir, Lake Gölbaşı, Kartalkaya Reservoir, Aslantaş Reservoir, Kılavuzlu Reservoir, and Hakkıbeyli Reservoir in Ceyhan Basin. Analyzes of chemical variables (total phosphorus (TP), total nitrogen (TN), nitrate (NO3) etc.) were made according to the standard methods. The relationship between phytoplankton species and environmental variables was assessed by canonical correspondence analysis (CCA) and weighted average regression. Phytoplankton trophic index (PTI), Mediterranean phytoplankton trophic index (Med-PTI), OECD and Carlson trophic index were used to assess the ecological status. The highest salinity, TN, and NO3 were measured in Hakkıbeyli Reservoir. A total of 204 species were identified during the study period. Scenedesmus communis, Ceratium hirundinella, Cyclotella iris, Fragilaria ulna, Cocconeis placentula, Aulacoseira granulata, Amphora ovalis and Gomphonema parvulum were commonly found. PTI showed that the studied ecosystems were at the medium/good ecological status and Med-PTI showed that the studied ecosystems were at the medium ecological status. Keywords: Phytoplankton, Ceyhan Basin, Lentic ecosystem, Med-PTI