Érosion des berges et effets sur les occupations du sol dans le bassin versant du Mayo Doumou : cas de la section Bédji bédji-Basgaré (Extrême-nord, Cameroun)

Land loss due to erosion constitutes an immense threat in the Sudano-Sahelian zones in general, and particularly in the localities of Bédji Bédji and Basgaré (district of Bogo, Far North Cameroon). This study aims to analyze the effect of erosion on the dynamics of land use, as well as on the balance of the banks of Mayo Doumou. To carry out this study, documentary research, direct field observations, and surveys were carried out, as well as a cartographic evaluation of the effects of this erosion was made thanks to the implementation of a georeferenced data under QGIS 3.16.0. The results show that the study area is facing very accelerated erosion, judging by the progressive leaching of soils, the generalization of gullying in the sector, the destruction of fields, roads and houses, the displacement of populations to other sectors of the basin, and material losses. Particularly regarding the banks, we note an annual retreat of between 0.90 m and 1.60 m depending on the sector, which will have caused the site to lose approximately 0.5 km² of land over the last 20 years. Solutions mainly based on revegetation have been implemented by the populations, even if their effectiveness appears to be low.