دراسة بيئية وتصنيفية للعوالق النباتية في مياه سد بكسا

This study was achieved through Mars 2011 until February 2012 the samples collected monthly from Baksa dam from different four location which differenced each other with chemical and physical qualities. We could in these study classified 132 species of phytoplankton distributed as 59 species belong to chrysophyta, 40 species of chlorophyta and 28 species of cyanophyta , 5 species of Euglenophyta. Physical and chemicalanalyzing ofBaksa waters showed the difference of values between studding regions, The concentration of Nitrate ions ranged between 17.7 mg/l at third location and 0.3 mg/l at second location, The highest rate to Phosphate ions was 18.8 mg/l and the less was 0.01mg/l, and it was noticed the difference in these values in the same region with the difference of period of time. The diversity and distribution of studied phytoplankton correlated with the environmental factors. It was noticed The abundance of cyanophytain the water of third location which near to the sewage channels which is suitable environment to these group of phytoplankton.