In numerous coastal aquifers, particularly in semi-arid and arid regions, the salinization of groundwaters is of strategic water resource importance, since it places limitations of the use of the water for urban water supply and agricultural use. The hydrochemical differentiation of the salinization processes is very complex as there is considerable hydrochemical variability due to superposition of different processes: marine intrusion, recycling of wastewaters, continental saltwater contribution and pollution phenomena by agricultural activities. In this book, we try to describe the...