The study was conducted to determine the level of interactions between aquatic algae and associate physical, chemical and biological factors. Because of the sharply defined environmental limit, the distribution and abundance of algae was observed to largely depend on the environmental factors. Temperature, Log of concentration (pH) and Electrical conductivity (Ec) was studied using portable HANNA/pH/Ec/ Temperature model 210. However Transparency was determined using 20cm diameter black and white painted secchi disc, Dissolved oxygen(DO) and Biological Oxygen Demand (BOD) were determine using AZIDE modification method, Nitrate-Nitrogen were determined using 210VGP, Phosphate-Phosphorus was determined using HACH DR/2000 Spectrophotometer. Monthly sampling from May 2010 May 2011 indicated that dissolved inorganic nitrogen concentration decreased while dissolved inorganic phosphorus concentration increased mostly in dry season resulting in increase in algal concentration and a shift from green algal dominance in wet season to blue green algae in dry season. Analysis of variance (ANOVA) indicated that cyanophyceae (blue green algae) were favored by high temperature and DIN: DIP ratio, if a further increase in nutrients concentration occurs the dominance of blue-green algal may pose potential health problems such as Cholera and Diarrhea. Similarly microcystis aeruginosa which is confirmed toxic green algae was observed and identified
Key words: Algae, effluent, environmental variables, Dissolve Inorganic Nitrogen (DIN), Dissolve Inorganic Phosphorus (DIP).
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