Research Journal of Microbiology1816-4935xxxx-xxxxScience International10.3923/jm.2007.228.238AkinyemiS. A.NwankwoS. A.FasuyiA. O.3200723Diatoms as indicator of pollution in Awon reservoir were studied for two years. Two set of water samples were collected, one for physico-chemical characteristics analysis and the other set for biological analysis. Pinnularia lata, P. mesolepta, Navicula rhychocephala, Aulacoseira granulata and Amphora were the most prominent diatoms that served as good indicators of pollution. These organisms predominated during the raining season than during the dry season. Weather conditions ere majorly responsible for the physical and chemical changes in thee reservoir. The wet season of the experiment was characterized by the influx of flood water and the consequent mixing of the reservoir water with attendant increase in transparency and nutrient levels. The dry season of the experiment was characterized by high conductivity and high silica level. The study suggests that the presence of any of the predominated organisms in the water is an indication of water pollution.]]>Akinyemi, S.A.,20002000Amuda, S.A.,19901990Anadu, D.I., A. Obioha and C. Ejike,19902081725Cox, E.J.,19751012Dakshini, K.M.M. and J.K. Soni,198287205209Egborge, A.B.M.,19793140517Imevbore, A.M.A.,1971203599600Khan, M.A., T. Fegbemi and C. Ejike,1983446671Vanlandingham, S.L.,1982Nwankwo, D.I.,198618996Patrick, R.,19641964pp: 325330Patrick, R. and C.W. Reimer,1966Vol. 2,pp: 13pp: 13Patrick, R.,19731973pp: 7695