Seasonal Variation of Phytoplankton in AL-Diwaniya River

Abstract

This study was conducted from January to October 2014, the samples were
collected monthly from four stations in AL-Diwaniya River at AL-Diwaniya city.
Phytoplankton species which are diagnosed during study period are (506) and the
numbers of common types in four sites are (61). Bacillariophyceae is dominate on
other classes and Chlorophyceae, Cyanophyceae, Dinophyceae then Chrysophyceae
and Euglenophyceae. The study shows that there are (150), (144), (118) and (94)
species in the first, second, third and fourth sites. The species that have highs numbers
are (Achnanthes, Cymbella, Nitzschia, Navicula). Other types are dominant in their
existence and number during study period (Cycltella comta, Cylotella Ocellata,
Cycletella meneghiniana, Cyleotella Kutzingana, Pediastrum somplex, Diatoma
elongatum and Cocconeis Placentula) During the study period, there are seasonal and
site changes in total number of phytoplankton which ranged between (440.61-2994.3
cell×103/L).