Evaluation of the Physicochemical Parameters and Phytoplankton Composition of Aiba and Erinle Reservoirs

Abstract

Physicochemical and biological characteristics of Aiba and Erinle reservoirs were studied to examine the suitability of surface water for drinking purpose. The study aims at comparing physicochemical parameters (such as heavy metals, phosphate, nitrate, pH etc) of the two reservoirs with permissible limits stipulated by World Health Organisation and other Environmental Protection Agencies; and also investigating the presence of pollution indicator phytoplankton species. Water samples were collected from two sampling stations of each reservoir and analysed for physicochemical parameters and phytoplankton composition to know the present status of the water bodies. The two reservoirs are alkaline in nature and some of the physicochemical parameters are above the permissible limits prescribed by World Health Organisation and other national and international bodies. This is supported by the presence of Nitzschia sp., Closterium sp. and Oscillatoria limosa that are regarded as pollution tolerant species. The presence of some toxigenic algae indicates the pollution level of the two water bodies.