| Abstrakt: |
Suitable evaluation and monitoring of water resources is pertinent for understanding its hydrogeochemistry. This research, therefore, appraised the hydrogeochemical dynamics, surface water-groundwater interactions with rocks, and meteoric water in the lower Niger River Basin, Nigeria, using geochemical analysis, statistical techniques, and ratio plots respectively. This entailed analyzing 5 rainwater samples and 51 surface water and groundwater samples for physicochemical parameters. Findings from the in-situ tests (pH, Temperature, TDS, EC), all indicated compliance with WHO guidelines except few hand-dug well samples that presented TDS and pH values that suggests pollution. The water facies for surface water and groundwater were shown to comprise 72% of Ca-Mg-HCO3water type while the rest is contributed by Ca-Mg-Cl (15%), Na-HCO3(9%), and Na-Cl/Na-SO4(4%). The Schoeller diagram showed predominant ionic content to be Ca > Na > Mg and HCO3> SO4> Cl for the surface water while for groundwater the arrangement is Ca > Mg > Na and HCO3> SO4> Cl revealing a similar source of ionic enrichment for both surface water and groundwater. The Pearson correlation projected strong positive correlations between Na+, Ca2+, and Mg2+, and between CO32−and HCO3−in both surface water and groundwater showing a strong relationship between ions in both water sources. Meteoric water contribution to both surface water and groundwater is not significant, since the concentrations of all ions are < 50% except for CO32−in groundwater. The saturation indices (SI) and chloro-alkaline indices show that the dissolution of halite, anhydrite, gypsum, and alkali feldspars accounts for the water chemistry while ion exchange predominantly defines the hydrogeochemistry of the groundwater. |
Full text from SpringerLink