2025-11-18 HYDROLOGICAL SCIENCES JOURNAL 2025 70(卷), 15(期), (2745-2761页)
In African arid and semi-arid lands, groundwater is a strategic resource. However, in some watersheds like Moulouya Basin in Morocco, the groundwater circulation and recharge mechanisms are still not well known. Hence, this study investigates the recharge and hydrodynamic interactions within aquifers through an integrated geochemical and isotopic approach. Hydrochemical facies reveal carbonate control on water chemistry, while elevated SO(4)2-, NO3-, and Cl- concentrations reach 465, 42, and 874 mg/L, respectively, indicating both geogenic inputs and anthropogenic impacts. Radiocarbon dating showed groundwater ages ranging from modern to over 30 000 years, revealing a dual system of shallow, vulnerable aquifers and deep fossil water bodies. Stable isotopes confirmed recharge from high-altitude zones in the Middle and High Atlas. A conceptual model highlights complex and connected multilayered aquifers with limited renewal potential. This work emphasizes the urgent need for integrated groundwater management to protect modern and ancient water resources in arid environments.