Seasonal variations of the phytoplankton biomass in Diyala River, Iraq.


The present investigation aims to study phytoplankton density and some ecological factors in Diyala River from March to October 2004. Two stations were selected in middle region of Diyala river. Results revealed that the ecological factors within the ranges: water temperature 20.1-31.3ºC, Electrical conductivity 877-1160 Ms/cm2, pH 7.6-8.2 and dissolved oxygen 8.1-11.7 mg/l). A total of 60 algal taxa on was identified dominated by diatoms, then green and blue greens algae in the studied stations. Higher cell numbers as at all 3057 cell/ cm3 and diatoms 1630 cell/cm3 were recorded in spring season in st.2. Seasonal variations of the cell numbers were discussed.