The researchers used a method called 137Cs to measure soil loss over the past 30 years in south-west Niger. They found that certain soil properties can be used as indicators of soil loss. By analyzing these properties, they identified different classes of soil sites with varying levels of soil flux. The study also revealed the influence of natural terraces and vegetation islands on soil redistribution. Topographic features were important in predicting soil movement, with surface wash and aeolian processes playing key roles in different areas. Overall, the research showed how soil properties and topography can help understand and predict soil flux in the study area.