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

In the present study, in order to determine the local (sampling stations) and temporal (seasonal) distribution phytoplankton in the Yuvacık Reservoir sampling was carried out in four seasons from two stations: from the entrance area of the streams to the dam (Y2) and from the dam embankment front (Y1). 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.1, 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 varied between stations, while sulfate (SO4), temperature (T) and pH values differed across seasons. According to Canonical Correspondence Analysis (CCA); Chlorella vulgaris and Melosira varians were associated 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. 1 and Fragilaria crotonensis were related with electrical conductivity (EC), ortho-phosphate (PO4-P), total phosphorus (TP) and pH. In the 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 station Y1 than station Y2.