Factors Controlling Groundwater Mineralization in Korhogo, Côte d’Ivoire: A Statistical Approach

Abstract

Groundwater is a major drinking-water source in northern Côte d’Ivoire, and understanding the processes governing its dissolved mineral content is important for groundwater protection. This study investigated the mechanisms controlling groundwater mineralisation in the Korhogo department using hydrochemical and statistical approaches. Forty-seven groundwater samples were examined through descriptive statistics, hydrochemical facies classification using a Piper diagram, and standardised principal component analysis. Field and laboratory measurements covered the physicochemical variables used to characterise the sampled groundwater. The groundwater was generally acidic and weakly mineralised, with a mean pH of 6.19 and mean electrical conductivity of 123.77 µS/cm. Four hydrochemical facies were identified: calcium–magnesium bicarbonate (56.76%), calcium–magnesium chloride–sulphate (29.73%), sodium–potassium bicarbonate (8.10%), and sodium chloride (5.41%). The first four principal components explained 75.27% of the total variance. The multivariate results indicate that groundwater chemistry is mainly associated with residence time and water–rock interactions, particularly silicate mineral hydrolysis, together with soil leaching and weathering processes. Secondary statistical associations indicate localised anthropogenic influence, especially where nitrogen species and potassium are involved. Overall, the results suggest that natural geogenic processes dominate groundwater mineralisation in Korhogo, while anthropogenic inputs contribute to spatial variability in selected locations. These findings support continued groundwater-quality monitoring in areas affected by agricultural and domestic activities.