Author(s)

Adedeji Idowu Aduwo, Israel Funso Adeniyi

Limnology and Hydrobiology Laboratory, Zoology Department, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria.

The physico-chemical water quality of the Obafemi Awolowo University Teaching and Research Farm Lake, Ile-Ife, Nigeria, was studied over an annual cycle (September 2006 to August 2007) almost 40 years after its impoundment in 1967. This was with a view to obtaining the then current state of physico-chemical water quality parameters with their variations in time and space as well as using some of the data obtained to evaluate the aging process of the lake for the 40 years of its existence. There was no significant (p > 0.05) horizontal variation (i.e. upstream-dowstream) in the physico-chemical characteristics of the lake whereas, Apparent-color, True color, Turbidity, Total Suspended Solids (TSS), Total Solids (TS) and Total Acidity increased significantly (p < 0.05) from the lake surface towards the bottom of the lake. On the other hand, water pH, Dissolved Oxygen (DO); Dissolved Oxygen Saturation (DO% Sat.) and Biochemical Oxygen Demand (BOD₅) decreased significantly (p < 0.05) from the lake surface towards the bottom of the lake. Dissolved Oxygen (DO), Dissolved Oxygen Saturation (DO% Sat.) and Nitrate ion (NO^-₃) were significantly higher (p < 0.05) in the dry season than in the rainy season while, True colour, pH, Conductivity, Total Hardness, Calcium ion (Ca²⁺), Magnesium ion (Mg²⁺), Potassium ion (K⁺) and Sulphate ion (SO^2-₄) were significantly higher (p < 0.05) in the rainy season than in the dry season. The lake water could be regarded as shallow, coloured, turbid, less transparent, slightly acidic, soft and well-buffered fresh-waterbodies with evidence of aging (i.e. transforming the lake from an oligotrophic status to a eutrophic waterbody). The results indicated that the lake is suitable for most of its applications with little or no adjustments as the case may be; except probably for drinking purposes where some microbial analysis may be necessary.

Inundation, Oligotrophic, Eutrophic, Aging, Man-Made, Spillway

Aduwo, A. and Adeniyi, I. (2019) The Physico-Chemical Water Quality of the Obafemi Awolowo University Teaching and Research Farm Lake, O.A.U. Campus, Ile-Ife, Southwest, Nigeria. Journal of Environmental Protection, 10, 881-899. doi: 10.4236/jep.2019.107052.