Quantification de la dégradation du paysage agricole et évaluation économique d'un aménagement approprié : cas du bassin versant Douimis (Tunisie)

In the context of climate change, soil erosion constitutes a significant threat to land conservation, water security, and ecosystem functioning. The study area covers Douimis catchment located in the northern part of Tunisia. The main objectives targeted, as well as the approaches considered in this present paper are 1- to assess the impact of climate change on soil loss based on RUSLE/GIS methodology, 2- to set an adaptation plan based on a participatory approach, then 3- to study its economic viability using Net Present Value (NPV) and Benefit-Cost Ratio (BCR) methods. The results showed that the basin is subject to a significant soil loss of 18 t/ha/year in the current situation. The impact of climate change has increased the erosion risk by 30% in 2050. This risk has been reduced by about 40% when introducing water and soil conservation measures. The economic analysis displayed that the Douimis Basin development plan constitutes an interesting investment opportunity that deserves the attention of local and national authorities in the search for funding. This shows the usefulness of investing in landscape management to prevent the degradation of natural resources.