EFFECTS OF SELECTED WATER QUALITY PARAMETERS ON PHYTOPLANKTON ABUNDANCE AND DIVERSITY IN RIVER CHEPKOILEL, ELDORET, KENYA

The study on the effects of water quality parameters on phytoplankton abundance and diversity in River Chepkoilel, Eldoret (Kenya) was done between October 2011 and February 2012. Three stations were selected; sampled upstream, midstream and downstream. A total of 31 genera of phytoplankton were identified, the most abundant phytoplankton in the bridge was Anabaena cirnalis (567 cells mgl-1), Aphanocapsa rivularis (545 cells mgl-1) and Coelomolon vestitoz (242 cells mgl-1). The least abundant phytoplankton in the Bridge was Schroidera setigera (3 cells mgl-1) and Scenedesmus maximus (6 cells mgl-1). Results indicated that many of the phytoplankton in River Chepkoilel are sensitive to physico-chemical fluctuations of water. There was increased diversity at Bridge from the month of October 2011 (H’=2.400) to the month of February 2012 (H’=2.528). This was due to a fairly conducive environment for phytoplankton production. A two way ANOVA test showed that there was a significant difference in pH, DO and conductivity (p<0.05) and temperature (p<0.05) in all stations.