Potentialité des données satellitaires Sentinel-2 pour la cartographie de l’impact des feux de végétation en Afrique tropicale : application au Togo

Climate warming is a global phenomenon which is affecting the whole climate system. One of its consequences is the longer duration of drought periods, which is increasing the frequency of bush fires. Uncontrolled wildfires disrupt the ecology and functions of ecosystems, sometimes eroding them. This study, focusing on satellite monitoring during the bush fire season in 2018-2019, offers a contribution to support bush fire management in Togo. We explore the potential of new satellite data from Sentinel-2 (S-2), available as open-access remote sensing data for optical detection of burned areas and mapping of both utilitarian and uncontrolled fires. The data can also be used to test the performance of bush fire mapping methods by means of the NBR index (Normalized Burn Ratio), initially designed for Landsat images to assess burned plant biomass. The results show the potential usefulness of S-2 images in mapping burned areas and a satisfactory performance of the NBR method with S-2 images. Mapping of bushfires shows that utilitarian fires account for 21.75% of all fires as opposed to 78.25% for uncontrolled fires. Together, the bush fires recorded destroyed plant cover over 5,878 km2, or 10.39% of Togo's surface area. The plant cover burned mainly comprises savannah land (33.12%), crops and fallows (24.48%), plantations (14.59%), open woodland (14.43%) and riparian forest (13.02%). The results obtained provide tangible evidence to support monitoring, awareness-raising, planning and development of bush fire prevention and management plans.