Seasonal Variation of Phytoplankton and Zooplankton Biomass in Correlation With Physio-Chemical Variables of Some Water Bodies in Dolly Smaquli, Erbil, Iraq

The seasonal variation of phytoplankton and zooplankton groups in correlation with physio-chemical variables has been examined by monthly water samples from eight distinct locations in Smaquli Dam and Streams within Dolly Smaquli in Erbil city, Iraq. The sampling time spans from September 2021 to August 2022. Nineteen physical and chemical variables were examined including Air and water temperature, Electrical conductivity (EC), Total dissolved solids (TDS), Turbidity, pH, Dissolved oxygen (DO), Biochemical oxygen demand (BOD5), Total Alkalinity, Total Hardness, Nitrite (NO2), Nitrate (NO3), Reactive phosphate (PO4), Ca+2, Mg+2, Na+, K+, SO4–2 and Cl–. The findings about planktonic communities revealed a range of total zooplankton numbers, which varied from non-detectable to 17,833 individuals. l–3. The overall population of phytoplankton amounted to 2971 cells. l–1 to 3,832,590 cells. l–1. The phytoplankton productivity and zooplankton total number were higher at Dam impoundment sites compared with Stream sites. However, the direct grazing relationship of zooplankton on phytoplankton was noticed in both types of ecosystems. The observed fluctuations in plankton’s functional groups throughout different seasons underscore the significance of physical and chemical variables. Canonical Correspondence Analysis (CCA) between environmental variables and dominant groups of phytoplankton and zooplankton indicated that environmental variables such as Water temperature, pH, Turbidity, DO, BOD5 and Nutrients are important factors that influence on monthly variation of plankton functional groups in freshwater ecosystem. Nevertheless, the status of the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) for all locations falls under the "Fair" category for drinking.