Spatial and Temporal Analysis of the Relationship between Phytoplankton Community Structure and Environmental Parameters of Yuvacık Reservoir

In this study, to determine the spatial (sampling stations) and temporal (seasons) distribution of phytoplankton, seasonal sampling was carried out at two stations (the reservoir embankment area-Y1 and the streams inlet-Y2) of the Yuvacık Reservoir. A total of 52 taxa were identified in the phytoplankton composition, including 30 Heterokontophyta, 9 Chlorophyta, 1 Cryptista, 4 Cyanobacteria, 5 Dinoflagellata and 3 Euglenophyta. Anabaena sp., Chlorella vulgaris, Fragilaria crotonensis, Prestauroneis crucicula, Melosira varians and Ulnaria ulna were recorded as the dominant species according to relative abundance of total biovolume. Nitrate nitrogen (NO3-N) values were different among stations, while sulfate (SO4), temperature (T) and pH values were different among seasons. According to Canonical Correspondence Analysis (CCA); Chlorella vulgaris and Melosira varians were related with NO3-N and SO4; while Ulnaria ulna, Prestauroneis crucicula, phytoplankton total biovolume (TBV), species richness (RICH), and species diversity (DIVERS) were correlated with temperature (T), nitrite nitrogen (NO2-N) and silica (Si). Moreover, Anabaena sp. and Fragilaria crotonensis were related with electrical conductivity (EC), ortho-phosphate (PO4-P), total phosphorus (TP) and pH. In Yuvacık Reservoir, when the riverine region (Y2) and the lacustrine region (Y1) compared, it was observed that the total biovolume, species number and diversity of phytoplankton were generally higher at Y1 station than Y2 station.