The importance of small temporary wetlands in arid and semi-arid zones for local development, the case of Ferlo in Senegal
Madina Ba, Mahefa Mamy Rakotoarisoa, Awa Fall Niang, Aude Nuscia Taïbi. The importance of small temporary wetlands in arid and semi-arid zones for local development, the case of Ferlo in Senegal. XIXe World Water Congress, Dec 2025, Marrakech, Morocco. ⟨hal-05419486⟩
Small temporary wetlands (STWs), which may be referred to as ponds, are aquatic ecosystems found in a variety of environments, generally small and shallow, whose water resources vary considerably as they flood intermittently and dry up seasonally or sometimes for several years, often every year, and sometimes unpredictably. These little-studied and therefore little-known STWs nevertheless present major socio-ecological challenges in dry zones, particularly in the Sahel. They are major water resources, as well as sites for grazing herds, cultivating crops and gathering food supplements, fruits, leaves, etc. They are also very important places of sociability, as poems from the Senegal Ferlo region tell us. Yet these STWs are particularly in decline on both global and local scales. The aim of this work is to study the STWs that crest the vast Ferlo plateaus in north-western Senegal, a region where they fill up during the summer rains and then gradually dry out with the dry season. To this end, we have combined a spatial analysis approach with field surveys to understand how these STWs function, and how they evolve in the context of climate change and hydro-agricultural development. At 4 sites from the south to the north of the Ferlo (Niakha, Loumbol Demakh, Thiudé Funangué and Koyli gotti), a spatial simulation was implemented using high-resolution topographic data (down to 7cm from UAV images), highlighting the hydrological connectivity linked to landscape organization and the complexity of their interaction, especially on this low-level plateau. Observations in the field and surveys of the people working around these ponds show their heritage interest, combining natural and cultural riches
Small temporary wetlands (STWs), which may be referred to as ponds, are aquatic ecosystems found in a variety of environments, generally small and shallow, whose water resources vary considerably as they flood intermittently and dry up seasonally or sometimes for several years, often every year, and sometimes unpredictably. These little-studied and therefore little-known STWs nevertheless present major socio-ecological challenges in dry zones, particularly in the Sahel. They are major water resources, as well as sites for grazing herds, cultivating crops and gathering food supplements, fruits, leaves, etc. They are also very important places of sociability, as poems from the Senegal Ferlo region tell us. Yet these STWs are particularly in decline on both global and local scales. The aim of this work is to study the STWs that crest the vast Ferlo plateaus in north-western Senegal, a region where they fill up during the summer rains and then gradually dry out with the dry season. To this end, we have combined a spatial analysis approach with field surveys to understand how these STWs function, and how they evolve in the context of climate change and hydro-agricultural development. At 4 sites from the south to the north of the Ferlo (Niakha, Loumbol Demakh, Thiudé Funangué and Koyli gotti), a spatial simulation was implemented using high-resolution topographic data (down to 7cm from UAV images), highlighting the hydrological connectivity linked to landscape organization and the complexity of their interaction, especially on this low-level plateau. Observations in the field and surveys of the people working around these ponds show their heritage interest, combining natural and cultural riches