Mohammed J.S.A. Al-Haidarey, Ibtihal A. Abdulmunem and Muhson C. Abbas
Abstract
The seasonal variation of phytoplankton community were studied in Bahr Al-Najaf Depression Reservoir (BNDR) during February 2015 to January 2016,fifty eight taxa which study by microscope, phytoplankton abundance ranged between 157Ãâ103ind.L-1to 285Ãâ103ind.L-1.The highest phytoplankton abundance were observed in spring and the lowest in summer. Cyanophyta, Chlorophyta, Chrysophyta and Bacillariophyta were the most important groups in terms of abundance and biomass. The preponderant and subpreponderant species change in accordance with the seasons. Canonical Correspondence Analysis (CCA) showed that the varieties of environmental factors affected the structure of phytoplankton community in each season. Cluster analysis showed that spring affected significantly on phytoplankton abundance;autumn affected significantly in phytoplankton diversity structure; the distribution of the species appearance subdivided into seven groups, the largest group contains eight species while the smallest group contains one species.