Resumen

Suitability of water from the Javita River basin for irrigating agricultural crops. RCTU [online]. 2025, vol.12, n.2, pp.29-37. ISSN 1390-7697.  https://doi.org/https://doi.org/10.26423/szw6tv78.

The study aimed to assess the suitability of groundwater from the Javita River basin, in Santa Elena, Ecuador, for irrigation of agricultural crops. Three sampling campaigns were carried out (May, August, and December 2024) in 25 wells-20 in December due to low-flow conditions-following NTE INEN 2176 and 2169 standards for sampling, and laboratory analyses were performed for pH, electrical conductivity, and major cations and anions; in addition, agronomic indices such as SAR, %Na, and residual sodium carbonate were calculated to evaluate risks of salinity and sodicity. The results showed a moderate average salinity close to 2 dS/m in the three periods, but with marked spatial variability and specific wells with very high salinity (up to 8,14 dS/m in May and 7 dS/m in December), indicating that water quality is not uniform and must be managed on a well-by-well basis. The pH remained slightly alkaline (7,4-8,3), within the acceptable range; SAR was always <10, %Na <60%, and RSC was negative, so the predominant hazard is not sodification or loss of infiltration but rather osmotic stress and potential soil salinization in particular sites. Water chemistry was dominated by dissolved Na, Ca, Mg, sulfates, and chlorides. It is concluded that, overall, the water is suitable for irrigation from the standpoint of sodicity, but it requires continuous monitoring, careful selection of salt-tolerant crops, and the application of leaching fractions in the most saline wells.

Palabras clave : irrigation water quality; salinity; sodicity; Sodium Adsortion Ratio; Residual Sodium Carbonate.