Monitoring and simulation of soil erosion in the Ethiopian Highlands on a plot scale

Abstract

Soil erosion is the main driving force for global land degradation. Soil erosion measurements are an important tool to assess soil loss under site-specific conditions and evaluate the impact of changes in land use on its magnitude. Based on this, adjusted management strategies can help to maintain or enhance the state of the soil. This work assessed soil loss rates on a plot scale in a 54 km² large agricultural catchment near Gondar, Ethiopia. At the experimental site, stone bunds were implemented in 2011 to prevent severe soil erosion. During the rainy season 2012 (July and August), three soil erosion plots with areas between 300 and 480 m² were installed and soil loss measurements were carried out. Soil loss from the three plots was 0.3, 3.0 and 4.7 kg m-2, respectively. Additionally, canopy and rock fragment cover, hydraulic conductivity as well as other soil properties were determined. Based on the data obtained from the field, the Water Erosion Prediction Project (WEPP) model was adjusted and calibrated. Furthermore, the model will be calibrated with more field-measured data sets of runoff and soil loss in the investigated watershed. In the future, it will then be used as demonstration tool to evaluate the response of soil erosion to changes in management practices or the implementation of soil and water conservation measures in the Ethiopian Highlands.