Dynamics of limnological features of two man-made lakes in relation to fish production

Abstract

Limnological features of Oyan and Asejire lakes, South-Western Nigeria, were investigated between July 2000 and December 2001. Rainy season (April-October) mean monthly rainfall values of 120.3 ±52.4 mm and 15.9 ± 10.3 were recorded for Oyan and Asejire lakes respectively, while corresponding dry season (November-March) values were 18.2 ± 34.7 and 4.2 ± 3.81 mm, respectively.. The mean surface water temperature, transparency, dissolved oxygen content and pH were 29.9 ± 2.34°C, 1.5 ±0.19 m, 7.1 ± 0.96 mg/L and 7.4 ± 0.43, respectively, in Oyan lake and for Asejire lake the values were 28.5 ± 1.91°C, 1.3 ± 0.35 m, 6.9 ± 1.33 mg/L and 7.4± 0.54, respectively. The physicochemical properties of the two lakes vary with seasonal changes in the rainfall of the drainage area. Oyan and Asejire lakes
exhibited features that are typical of tropical environment. The high dissolved oxygen content values indicate that the water bodies can successfully support aquatic life including fish