Introduction
Between the Rhône River and the Mediterranean Sea, the Camargue Biosphere Reserve covers the entire biogeographical delta of the Rhône, since its revision in 2006. An immense natural area, located between two very densely populated regions at the gates of the agglomerations of Montpellier, Nîmes, Arles and Marseille and the industrial site of Fos-sur-Mer.
An essentially horizontal landscape, the Camargue nevertheless has many bulges that are sources of diversity: alluvial bulges of the old and current branches of the Rhône and dune ridges created by the marine currents and historical shorelines of the Mediterranean Sea. Between these areas, which are still partly forested, in the depressions, there are lowlands occupied by lagoons bordered by salt steppes, reed marshes partly used for reed cutting and ponds - the largest of which, the Vaccarès, covers 6,500 hectares.
The salt content of the soil and water, the wide variations in flood conditions and the vagaries of the Mediterranean climate determine the biological richness of the Rhone delta.
The agricultural landscapes of the Camargue are composed of wet meadows and sansouïres dedicated to the breeding of bulls and horses, former marshes converted into rice fields, lagoons developed for salt exploitation and market gardening and viticulture on the dunes. The hydraulic mesh necessary for this agriculture is omnipresent. It influences the management of these agricultural areas and indirectly that of adjacent natural environments.