Investigation of the land use/land cover change in the Upper Oue´me´ Catchment, Benin (West-Africa) for the set up of a coherent development plan

Within the last decades a dramatic change occurred in the land use/land cover in West-Africa. The reasons causing this evolution are manifold, e.g. the population increase, the climatic change and therewith related changes of the hydrological conditions. The alteration of the hydrologic/climatic conditions have a strong influence on the living conditions of the local inhabitants. When the basic conditions of life (water, food) are at risk, the potential for conflicts amongst the citizens increases sharply. To give prognoses for the future development, and for risk assessment it is important to investigate the land use/land cover changes and their interaction with the hydrological cycle within the last decades. Besides the detailed documentation of the changes it is necessary to understand the mechanisms and the triggers of land use change. Within the framework of the IMPETUS Project the land use changes in the Upper Oue´me´ Catchment (Benin) between 1975 and 2000 are investigated. Thereby two temporal scales matter: on one hand the seasonal vegetation dynamics and on the other the longer term decennial changes. For that task different satellite systems are utilised. The description of the seasonal vegetation dynamics within a period of 18 months is done on the basis of NOAA-AVHRR images. Additional Landsat-7 ETM, ENVISAT and MODIS scenes provide information about the land use/land cover in a higher resolution. This analysis of the vegetation dynamics are backed by intensive "ground truth" campaigns during which data about the leaf area index, the biomass and the spectral signatures are collected in the test area