Search Results
Now showing 1 - 1 of 1
- Impact of irrigation return flow induced mineral weathering and ion exchange reactions in the groundwater was studied in Limpopo region, South Africa. Based on EC (>500) and HCO3 (>150mg/l), groundwater samples are classified into two groups due to its heterogeneous nature. Water types in group 1 and 2 wells are Ca-Mg-Cl-SO4 and Ca-Mg-HCO3, respectively. Gibbs plots, bivariate plots and ionic ratios (Mg/Na vs Ca/Na; HCO3/Na vs Ca/Na; mCa + Mg vs mHCO3; mNa + K vs mHCO3; Ca + Mg-HCO3-SO4 vs Na + K-Cl; mCa + Mg/HCO3 vs Cl; Ca + Mg/SO4 +HCO3 >1; Na/Cl ratio; Cl + SO4 vs HCO3), chloro alkaline indices (CAI, CA2) and Pearson correlation analysis imply that groundwater chemistry is influenced by mineral weathering (carbonate > silicate minerals), reverse ion exchange and irrigation return flow. In group 1 wells, Cl + SO4 and HCO3 have strong positive correlation and both increases together, suggesting induced mineral weathering caused by nitrification and wastewater infiltration from the surface. Group 2 wells are generally deep with low groundwater level fluctuation and high concentration of major ions. Overall, water chemistry in the group 1 wells is highly affected by the contamination sources than group 2 wells.
- 1
- 2
- 0