Assessment of physicochemical characteristics of lower River Niger at Kpata, Adankolo and Gadumo Stations in Kogi State, Nigeria

The present work was conducted to study the physicochemical parameters of lower River Niger at Lokoja and Ajaokuta local government area of Kogi state, with the aims to determine the physical and chemical situation of the River at this point in time, compare the physical and chemical situation of the river with earlier work done on River Niger and other relevant water bodies by relevant authors also to determine its suitability for fish growth and survival at this point in time. Water samples were collected for four month (January to April) at three sampling site (two site from Lokoja and one from Ajaokuta local government area) and analysed for various physicochemical parameter. The mean temperature values ranged from 23.55 - 28.350C at Kpata station, 24.65- 29.750C at Adankolo station and 23.90-28.900C at Gadumo station. The mean pH values ranged from 6.69-8.15 at Kpata station, 6.60-8.30 at Adankolo station and 6.10-8.20 at Gadumo station. The mean electrical conductivity values ranged from 68.50-135.50µS/cm at Kpata station, 68.00-122.50 µS/cm at Adankolo station and 68.00-122.50 µS/cm at Gadumo station. The mean dissolved oxygen (DO) values ranged from 6.10-9.30 mg/l at Kpata station, 5.65-7.78 mg/l at Adankolo station and 6.10-9.30 mg/l at Gadumo station. The mean transparency values ranged from 0.31-0.60m at Kpata station, 0.31-0.60m at Adankolo station and 0.30-0.44m at Gadumo station. The mean biochemical oxygen demand (BOD) values ranged from 2.10-2.95 mg/l at Kpata station, 2.05-3.25 mg/l at Adankolo station and 2.10-4.00 mg/l at Gadumo station. The mean nitrate values ranged from 0.02-0.05 mg/l at Kpata station, 0.02-0.03 mg/l at Adankolo station and 0.02-0.04 mg/l at Gadumo station. The mean phosphate values ranged from 0.48-0.61 mg/l at Kpata station, 0.51-0.65 mg/l at Adankolo station and 0.49-0.64 mg/l at Gadumo station. The study indicated that the mean value of the studied parameters which include pH, temperature, dissolved oxygen, Electrical conductivity, biochemical oxygen demand, nitrate, transparency and phosphate of the River compares slightly favourably with the work of other researchers and within the range that support fish growth and survival. This indicates that the river is in a healthy state and is favourable for fish growth and survival. Keywords: physiochemical parameter, water, river Niger, fish growth