Study of phytoplankton of Sanandaj Azad Dam Lake

Azad reservoir Dam is located in Sanandaj city in Iran, at ۴۶°۳۳' longitude and ۵۵°۲۰' North latitude, upstream of Benider village and on Kumasi River. The field activity of this research was done seasonally for one year. According to the size of the lake, the number of ۵ stations in the lake was determined. Phytoplankton was sampled by Neskin from three surface layers, the middle layer of the reflective layer and the layer near the bottom of lake. Then, phytoplankton samples were immediately fixed with ۴% formalin and then identified and examined under a microscope with X۱۰, X۲۰, X۳۰ magnification. The results of investigation the composition and diversity of phytoplankton species showed that a total of ۵۴ species were identified, and in this study, ۶ phytoplankton groups Bacillariophyta, Pyrophyta, Cyanophyta, Chlorophyta, Euglenophyta and Chrysophyta were observed with ۲۰, ۹, ۶, ۱۶, ۲ and ۱ species, respectively.The seasonal investigation of the diversity of phytoplankton species revealed that ۲۳, ۲۵, ۲۵ and ۱۸ species were recorded in spring, summer, autumn and winter, respectively, and the highest species diversity was related to summer and autumn with ۲۵ species. Also, the population changes of ۶ phytoplankton groups in the lake were observed to have the highest density of phytoplankton in the autumn season with an average of ۲۳۹۷۹۳۸±۳۷۵۰۰۰۰ numbers per liter and the lowest density of phytoplankton in the summer season was ۱۲۷۴۸۱±۹۰۶۵۶.

Keywords:

phytoplankton , Diversity , Density , Biomass , Sanandaj Azad Dam