Study of the Effect of Himreen Dam on the Phytoplankton Diversity in Dyala River, Iraq

Abstract
In present study three stations are located on Diyala River has been investigated to study phytoplankton community, the first station was located in jalawlaa area, second station in Himreen impoundment, while the third station is located after the Himreen Dam in Al-Soddur area, A total 134 taxa of Phytoplankton were identified during the study period, 63, 82 and 84 were identified in stations 1, 2 and 3 respectively. The higher density of Phytoplankton observed in station 3, result ranged between 21.16 - 23.88 × 102 cell/l during September and October respectively, then station 2 which has density ranged between 18.44 - 66.188 × 102 cell/l during January and September respectively, while the station 1 has the lowest values during the study comparable to other stations, the result ranged between 5.495 - 70.62 × 102 cell/l during January and April respectively. Species Richness Index ranged from 2.9 - 7.46 in station 1, 4.08 - 7.85 in station 2 and 5.71 - 8.77 in station 3. The result revels that the station 3 show to increase in Richness index value in the most of the months comparable to other stations. The Similarity index also has been calculated among the common species of Phytoplankton through the three station by using the Hierarchical cluster analysis is the highest Similarity percentage in reach in 43.5% for the common species of Phytoplankton between stations 2 and 3.