Water quality assessment of Owiwi River for potential irrigation of vegetables
Understanding water quality used for irrigation and its potential negative impacts on crop growth are important for optimization of crop production. The study involved the assessment of hydro-chemical properties and chemical indices of Owiwi river for irrigation of vegetables from the measured quality parameters and analyzed for important quality indices following standard test procedures. The study revealed that pH of water was acidic in nature resulting in low residual sodium carbonate (RSC) values showing dominance of dissolved CO3, attributed to dissolution of limestone dominant in the study area. The water was regarded as permissible water based on electrical conductivity (EC) and total dissolved solids (TDS), implying non detrimental salinity hazard in the soils. Excessive Na content (> 250 MMg/L) in water reduces the permeability thereby influencing availability of water for the plant usage, obviously associated with low EC and sodium adsorption ratio (SAR) observed in the river water. The excess hardness resulting from high content of calcium and magnesium ions derived from limestone and chalk is undesirable mostly for esthetic reasons like plumbing of irrigation systems. Generally, the water can be classified as good for irrigation of vegetable on the bases of PI, MAR, % Na, SAR and % yield.
Keywords: Hydro-chemical, permeability, soil, limestone, yield.