Assessing the Influence of Multiresolution DEMs on Soil Loss Prediction using the RUSLE Model in Central Morocco

Abstract

The topography plays a significant role in determining the rate of soil loss. The Digital Elevation Model (DEM) retrieved from earth observation products can be used to calculate the slope length and steepness, which are important factors in the Revised Universal Soil Loss Equation (RUSLE) used to estimate soil erosion. In the present study, the effect of two DEM resolutions (30m and 90 m) on RUSLE model results was assessed and used to quantify the rate of soil loss in Settat province (Morocco), specifically in certain abandoned quarries. As a result, DEM-30 and DEM-90 soil erosion rates vary from 0 to 282.77 t.ha-1.yr-1 and 0 to 13.79 t.ha-1.yr-1, respectively. At the quarry level, the abandoned quarries showed soil loss rates ranging from 0 to 7.92 t.ha-1.yr-1 for DEM-30. Contrary to this, the soil loss rate for DEM-90 data was zero. To summarize, for more relevant and detailed conclusions, high-resolution data must be used to collect more information and describe the erosion process with as much detail as possible, especially for small areas.