The Plio-Quaternary aquifer of Jerba Island (Tunisia), the Upper Miocene-Pliocene-Quaternary aquifer of Tripoli (Libya), the Plio-Quaternary aquifer of Nador plain (Algeria), the Bou Areg Plio-Quaternary aquifer (Morocco), the Miocene carbonate aquifer of Porto Torres (NW Sardinia, Italy) and the Pleistocene oolitic aquifer of the Baghoush area (Egypt), are essential contributor sources of drinking water and irrigation water for agricultural needs. They are increasingly being degraded by salinization processes, essentially allied with groundwater over-exploitation. In this study, a hydrogeochemical investigation, by interpretations of conservative dissolved ions was used to probe the main mechanisms controlling groundwater salinization and to characterize the associated hydrogeochemical processes occurring in Mediterranean coastal aquifers. Groundwaters of the different aquifers are of meteoric origin and they mostly flow toward the coast. Based on EC and ionic ratios, a hydro-chemical zonation of water types (ranging from Ca-HCO₃, Na-HCO₃, Ca-Mg-Cl-SO₄, Ca-Cl to Na-Cl) from recharge areas toward the coast is revealed. This zonation is mainly controlled by migration and mixing of saline waters with regional groundwaters. The behaviour of the major ions, the adherence of the majority of ion/Cl ratios and molar ratios characterising salinity in function of [Cl⁻] indicate that besides mixture with seawater, groundwater chemistry of the six aquifers is also influenced by evaporation, weathering of silicates, cation exchange and anthropogenic pollutants. The study provides insights into the hydrodynamic and geochemical relationships between freshwater and seawater at different Mediterranean coastal aquifers and provides regional authorities with a basic tools for sustainable water management aiming to limit seawater intrusion.

赫尔巴岛（突尼斯）的上新世-第四纪含水层，的黎波里（利比亚）的中新世-上新世-第四纪含水层，纳多尔平原（阿尔及利亚）的上新世-第四纪含水层，博阿雷格的上新纪-第四纪含水层（摩洛哥），波尔图托里斯（意大利西北撒丁岛）的中新世碳酸盐岩含水层和巴古什地区（埃及）的更新世橄榄岩含水层是满足农业需求的饮用水和灌溉水的重要来源。它们越来越被盐碱化过程所降解，而盐碱化过程基本上与地下水的过度开采有关。在这项研究中，通过对保守溶解离子的解释进行了水文地球化学调查，以探讨控制地下水盐碱化的主要机制，并描述了地中海沿岸含水层中发生的相关水文地球化学过程。不同含水层的地下水起源于流星，它们大部分流向海岸。根据EC和离子比率，对水类型进行水化学分区（范围为Ca-HCO_{如图3所示}，揭示了从补给区向海岸的Na-HCO ₃，Ca-Mg-Cl-SO ₄，Ca-Cl至Na-Cl。该分区主要是通过盐水和区域地下水的迁移和混合来控制的。主要离子的行为，大多数离子/氯比和摩尔比在[氯的功能表征盐度的粘附^-]表明，除了与海水混合外，六个含水层的地下水化学也受到蒸发，硅酸盐的风化，阳离子交换和人为污染物的影响。这项研究提供了对地中海不同含水层淡水与海水之间的水动力和地球化学关系的见解，并为区域当局提供了旨在限制海水入侵的可持续水管理的基本工具。