LAND USE DYNAMICS AND MORPHOLOGICAL EVOLUTION OF MAN-MADE LAKE SYSTEM OF YAMOUSSOUKRO, CÔTE D'IVOIRE

The municipality of Yamoussoukro encloses ten man-made lakes which have been designed for the embellishment of the city and the regulation of rainwater. However, despite their ecological, tourist and economic importance, human activities in the lake watersheds are causing a deterioration in water quality and siltation of the lakes' reservoirs. A study of land use was carried out through an analysis of satellite images from 1988 to 2018, coupled with a sedimentological study to assess the dynamics of land use and its impacts on the man-made lake system of Yamoussoukro. Land use and bathymetric maps show that the watershed suffered a significant degradation from 1988 to 2018. The resulting erosion, wastewater and household waste dumped into the lakes through a lack of adequate sanitation system accelerate the deterioration of the lake environment. The siltation and eutrophication of the Yamoussoukro lakes are very noticeable and pronounced. We are thus witnessing the gradual disappearance of these water bodies. The restoration of the integrity of the lakes and the implementation of a monitoring plan for the lake environments of Yamoussoukro city are necessary to embellish the city, improving the quality of the environment, developing tourism and preserving biodiversity.