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Abstract Background The widespread land degradation in Ethiopia has necessitated extensive soil and water conservation interventions over the last four decades. Despite these the degradation of land continues. The conservation interventions in most cases were, and still are, predominantly top-down approaches following government directives. The success of these blanket approaches has been limited and an alternative approach needs to be devised. This paper attempts to identify alternative options for selecting appropriate soil and water conservation technologies based on the biophysical suitability of the landscape. Results The results of this study suggest that with appropriate soil and water conservation measures, it is possible to reduce soil loss within the Blue Nile Basin by up to 600 million tons 46% within 5–10. The statistics on net soil loss reduction also indicate that successful implementation of conservation measures in only four administrative zones (out of 17) can potentially reduce up to 60% of the total soil loss in the Basin. Conclusion Landscape level modeling of soil and water conservation has enabled identification of appropriate conservation measures that can are suited to particular biophysical niches. A targeted approach to soil and water conservation is more efficient in terms of both financing and labour, in contrast to the traditional blanket approaches of the past.

Abstract. Every year Africa is hit by extreme floods which, combined with high levels of vulnerability and increasing population exposure, often result in humanitarian crises and population displacement. Impact-based forecasting and early warning for natural hazards is recognized as a step forward in disaster risk reduction, thanks to its focus on people, livelihoods, and assets at risk. Yet, the majority of the African population is not covered by any sort of early warning system. This article describes the setup and the methodological approach of Flood-PROOFS East Africa, an impact-based riverine flood forecasting and early warning system for the Greater Horn of Africa (GHA), with a forecast range of 5 d. The system is based on a modeling cascade relying on distributed hydrological simulations forced by ensemble weather forecasts, link to inundation maps for specific return period, and application of a risk assessment framework to estimate population and assets exposed to upcoming floods. The system is operational and supports the African Union Commission and the Disaster Operation Center of the Intergovernmental Authority on Development (IGAD) in the daily monitoring and early warning from hydro-meteorological disasters in eastern Africa. Results show a first evaluation of the hydrological reanalysis at 78 river gauging stations and a semi-quantitative assessment of the impact forecasts for the catastrophic floods in Sudan and in the Nile River basin in summer 2020. More extensive quantitative evaluation of the system performance is envisaged to provide its users with information on the model reliability in forecasting extreme events and their impacts.