Title : Assessment of the physicochemical parameters and fish composition of ogbese river, Ondo State, Nigeria
Abstract:
Physicochemical properties play essential roles in the maintenance of healthy aquatic ecosystems. The need for water quality monitoring is paramount to safeguard the public health and also to protect the water resources in Nigeria from pollution and degradation. Hence, this study aimed at assessing the physicochemical parameters and fish composition of Ogbese River in Ogbese, a rural village in Ondo State, Nigeria. A total of sixteen samples of water were collected fortnightly during the months of February to April, 2023. Some physicochemical parameters were assessed including temperature (23.560C ± 2.03), alkalinity (96.8mg/L±10.4), pH (7.5±0.4), total hardness(105.3mg/L ± 26.7), total suspended solids (51.6mg/L ± 12.4), total dissolved solids (102.1mg/L), total solids (153.6 ± 12.4), DO (5.2mg/L±1.7), BOD (2.6mg/L±0.6), COD(4.0mg/L±1.4), acidity (65.5mg/L ± 9.2), sulphate (15.7±6.5), nitrate (9.5mg/L ± 4.8), and phosphate(18.4±3.7) respectively. All the physicochemical parameters assessed were within the range of values recommended by WHO, NIS and FEPA with the exception of dissolved oxygen, phosphate and nitrate. For the fish composition of this river, a total of two hundred and sixty-two (262) fishes belonging to seven different species were recorded. The species of fishes caught are; Clarias gariepinus, Heterobranchus bidorsalis, Oreochromis niloticus, Tilapia zilli, Parachanna obscura, Malapterurus electricus, and Hepsetus odoe. Among the fish species, Clarias gariepinus have the highest population abundance (34%) while the least species of fish obtained was Hepsetus odoe (2%). In conclusion, Ogbese River is of good quality fit for domestic and agricultural purposes except for the excessive lead, phosphate, nitrate and dissolved oxygen content that needed to be checked and controlled. However, further study is recommended on the source and quantification of heavy metals present in the river for timely intervention to public health advantage.
Key Words: Physicochemical parameters, Fish, Ogbese River, Ondo State, Pollution.