Food security and water availability in data-poor regions: Five scenarios to assess land-use impact in the Tikur Woha catchment, Ethiopia Central Rift

In the Horn of Africa both the economy and the population are growing rapidly, which results in changes in land use. For instance in Ethiopia, forests and grazing land have been converted into cropland, affecting both land degradation and water availability. As a result, soil erosion increases and the base flow of rivers lowers, threatening food supply and access to water. To assess the impact of land-use changes on catchment hydrology and land degradation, several scenarios are created for a case study in the Ethiopian Central Rift Valley, the Tikur Woha catchment. These scenarios are: 1) a baseline scenario with a dominant forest cover, 2) current land-use and management settings, 3) a scenario projecting the current land-use trends, which comprises a shift to the cultivation of cash crops, such as sugarcane and khat, and 4) current government policy to remove khat farms from steep slopes as a countermeasure for land degradation. The Soil and Water Assessment Tool (SWAT) will be used to quantify these impacts. Insight into the land-use impact on the hydrology of the catchment, thereby quantifying irrigation and land degradation, will be valuable for land-use and water managers to achieve food security and water availability.