Details

Autor(en) / Beteiligte

• Farid, Intissar
• Trabelsi, Rim
• Zouari, Kamel
• Abid, Kamel
• Ayachi, Mohamed

Titel

Hydrogeochemical processes affecting groundwater in an irrigated land in Central Tunisia

Ist Teil von

• Environmental earth sciences, 2013-03, Vol.68 (5), p.1215-1231

Ort / Verlag

Berlin/Heidelberg: Springer-Verlag

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Detailed hydrogeochemical investigation has provided new information concerning the major factors and mechanisms controlling the groundwater chemistry of Chougafiya basin. The hydrogeochemical characteristics of groundwaters comprise three main types: Cl–SO 4 –Ca, Cl–SO 4 –Na and Cl–Na. Hydrochemical characteristics based on the bivariate diagrams of major (Cl − , SO 4 2− , NO 3 − , HCO 3 − , Na + , Mg 2+ , K + and Ca 2+ ) and some trace (Br − and Sr 2+ ) ions, mineral saturation indices and hierarchical cluster analysis indicate different origins of groundwater mineralization. The water–rock interaction (dissolution of evaporitic minerals), followed by cation exchange reactions with clay minerals, constitute the main processes that control groundwater salinization. However, the chemical composition of brackish groundwater in the central and southern parts of the study area is influenced by a mixing process with Sabkhas salt groundwater. The mixing proportions inferred from chloride mass balance prove that the contribution of Sabkhas groundwater to Quaternary aquifer ranges between 2.7 and 9.1 %. These intrusion rates reflect the progress of the saltwater–freshwater interface, which is mainly controlled by the piezometric level variation and the distance to the Sabkhas.