Epipelion community structure in tigris river within Baghdad City, Iraq

Five sites were selected along the river within Baghdad city during November2019 to July 2019, to study the qualitative and quantitative of epipelion diatoms. A total number of 186 species of epipelic diatoms belong to 59 genera were identified. These genera are belong Bacillariophycaeae with relative abundance of (79–85.8%), followed by Fragilariophyceae (8.61–12.7%) and Coscinodiscophyceae (3.5–8.9%). Temporal and spatial variations were observed. The lowest total cell number of diatoms (270 cells×10⁴/cm³) was at site for Coscinodiscophyceae and the highest number (315×10⁴/cm³) at site 5 for Baciliariophyceae. Achnanthidium minutissima, Cocconies placentula, Gomphonema parvulum, Aulacoseira granulata, Nitzschia frustulum, Navicula radiosa and Ulnaria ulna were recorded in a high cell number throughout the study period, Most abundant species belonged to Bacillariophycae which reflect the impact of pollution on water quality of the river.