Synergism between Season, pH, conductivity and total dissolved solids (TDS) of Imo River quality for agricultural irrigation

Quality of fresh water sources as influenced by season and physicochemical characteristics is a major consideration for use in agricultural irrigation programs. Seasonal values and variations of pH, Conductivity, and Total Dissolved Solids (TDS) and their interactions in Imo River quality were determined under standard analytical methods. Water samples were collected for two seasons - dry and rainy, at seven major locations of human activities - Ekenobizi, Udo, Owerrinta, Alulu, Owaza, Akwette and Obigbo along the River. There were significant variations in seasons (P < 0.05) for all parameters at all the locations. Conductivity and TDS values increased during the rainy season than during the dry season. The pH (5.18 - 6.35) at some locations was acidic. Conductivity (0.01 - 64.00 μS/cm) and TDS (1.9 - 1600mg/L) did not exceed acceptable standards for irrigation water. Correlation at R = 0.85 showed that as the pH increased, TDS and Conductivity increased and as TDS increased, the Conductivity increased. This implied that increased rainfall and subsequent soil erosion and anthropogenic activities might have increased the concentration of ions in the River. Ions in the River might be absorbed by plants and might also accumulate to concentrations high enough to cause crop damage or reduced crop yields on irrigated soils. An acidic pH value is an implication that the River might need further evaluation. The values are satisfactory for the use of Imo River for agricultural purposes (irrigation).