Mapping soil erosion and analyzing its severity using the RUSLE model and local farmers' perception in the agricultural area of Rwanda

Modelling soil erosion linked with the local farmers' perception is a vigorous way to assess the state of soil erosion risk. However, the combination of model results and local farmer's perceptions was rarely considered as an influencing factor of soil erosion risk in Rwanda, especially in the agricultural areas of the western province. This study used the Revised Universal Soil Loss Equation (RUSLE) model to estimate the status of soil erosion and develop a soil erosion severity map. Therefore, the model results were associated with local farmers' perceptions to analyze the erosion severity and assess different control measures for soil erosion risk reduction. The results revealed an average soil loss of about 113.9 t ha(-1) y(-1) with an annual average potential soil erosion risk of about 508.3 t ha(-1) y(-1). The southeast and northwest portions of the area are classified as having an extremely high potential soil erosion risk, which occupied 38.62% of the study area. Moreover, it was found that 100% of respondents were aware of the soil erosion incidents where among them, 90% revealed that the high topographic gradients and excessive rainfall characteristics were responsible for the high soil erosion risks. The combination of RUSLE and local farmers' knowledge and experience on soil erosion risk assessment in Rwanda increased the trustworthiness of soil erosion-based model applications in mountainous and tropical areas. Therefore, these findings provided the insightful information that can help to support the sustainable soil conservation measures and appropriate land use planning.