F.I. Nazhmudinova, A.S. Qodiri, I.M. Rakhimov

Annotation:

This study investigates the hydrochemical characteristics of groundwater in the study area. Physical and chemical parameters including pH, electrical conductivity (EC), major cations (Na⁺, K⁺, Ca²⁺, and Mg²⁺), and major anions (HCO₃⁻, Cl⁻, SO₄²⁻, and NO₃⁻) were analyzed to evaluate groundwater quality. The results indicate that the groundwater is predominantly of the Ca–Mg–HCO₃ hydrochemical type. Nitrate and sulfate concentrations were compared with the World Health Organization (WHO) drinking water guidelines. Most groundwater samples were found to be suitable for drinking purposes. Dissolution of carbonate minerals was identified as the main process controlling groundwater chemistry. The hydrochemical composition of the waters reflects the influence of water-rock interaction processes and the dissolution of carbonate minerals. The concentrations of major ions vary among different sampling points, indicating the influence of geological and hydrogeological conditions in the study area. The obtained results are important for assessing groundwater quality and determining the possibility of using groundwater for drinking water supply and other water-use purposes. They can be used to develop recommendations for the Паёми политехникӣ.  rational use, protection, and management of groundwater resources in the region.

Keywords: groundwater, hydrochemistry, bicarbonate, nitrate, sulfate, drinking water, Tajikistan.