Fish Pond Effluent Effect on Physico-chemical Properties of Soils in Southern Guinea Savanna,

Abstract

This work studied the effect of fish pond wastewater, proximate and mineral analyses of the fish feeds from commercial fish ponds on receiving soils in the southern Guinea Savanna ecological zone of Minna, Nigeria. The study con-ducted during the dry seasons of the years 2015 and 2016 between January and May. Four sets of soil samples were collected at varying distances from the various fish ponds and analysed for physicochemical properties, Particle size analysis and Exchangeable Acidity. Similarly, two different sets of water samples were collected each from various farms studied and analysed for physicochemical properties such as pH, Ec (Electrical conductivity), TDS (Total dissolved solids), Alkalinity, Total Hardness, Turbidity, Temperature, DO (Dissolved Oxygen), BOD (Biological oxygen demand), Calcium, Magnesium, Sodium and Potassium. Average results obtained for the two dry seasons for the soil samples around the fish farms showed that: pH 6.33 - 7.24, Organic Carbon 2.03 - 6.00 g/kg, Available Phosphorus 7 - 10 mg/kg, Total Nitrogen 0.95 - 2.10 g/kg, Exchangeable Bases and Exchangeable Acidity 0.02 - 0.06 Cmol/kg were within the permissible limits of FAO and WHO. The various parameters were within the permissible limits for fish production. The fish wastewater had Electrical Conductivity 118 - 230 μS/cm, pH 6.79 - 7.10, and Biological Oxygen Demand 3.0 - 6.0 mg/L. In conclusion, the wastewater from fish farms is good sources of fertiliser to the surrounding farmlands.