The geo-environmental influence on hydrogeochemical conditions in the Tanjaknangsi volcanic region

Abstract Groundwater in volcanic areas flows from the recharge to discharge, and dissolving rock minerals undergo hydrochemical changes. Anthropogenic influences form of increasing built-up land plantation activities upstream raise concerns about changes groundwater hydrochemistry. Hydrogeochemical environmental characterization regions is essential trace rock-water interaction. This study aimed determine geo-environmental influence on hydrogeochemical conditions Tanjaknangsi areas. The methods used were statistical analysis, bivariate Piper diagram. During dry season, 16 samples taken, consisting five dug wells, nine drilled two springs. process major ions characterized by weathering silica. concentrations cations Ca 2+ > Na + K Mg , while anion HCO 3 − Cl SO 4 . correlation analysis shows that strongly correlated with anion. Hierarchical dendrogram was influenced interaction anthropogenic influences; piper diagram dominant facies area CaCl, CaMgCl, CaMgHCO NaHCO dominated groundwater-rock interaction, factors downstream area. Residues such as agriculture, plantations, livestock will increase levels NH -N, 2- ions.