Wastewater quality assessment for agricultural crop irrigation in Mezquital Valley, Hidalgo

Abstract

In this study, the concentration of ions Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO_3-, Cl- and SO₄^2-, pH, and electrical conductivity (EC) in wastewater from Mexico City was determined. The objective was to assess the water quality and to estimate the risk of salinization and sodification of the irrigated soils in the Mezquital Valley. Wastewater was classified as bicarbonated-sodic with slightly alkaline pH (Q₃ = 8.11). The minimum and maximum EC values were 0.278 dS m^-1 and 3.684 dS m^-1 (Q₃ = 1.890 dS m-1), the sodium adsorption ratio (SAR) was less than 14.12 mmol L^-1 in 95% of water samples. The mean value estimate for the exchangeable sodium percentage (ESP), for sandy soil, was 5.95, for loam soil 9.34 and for clay soil 12.74. Wastewater use in crop irrigation may induce salinization and sodification processes in the soil.