Soil loss estimation using RUSLE model, GIS and remote sensing techniques: A case study from the Dembecha Watershed, Northwestern Ethiopia

• Published in: Geoderma Regional Vol. 11; pp. 28 - 36
• Main Authors: Ostovari, Yaser, Ghorbani-Dashtaki, Shoja, Bahrami, Hossein-Ali, Naderi, Mehdi, Dematte, Jose Alexandre Melo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2017
• Subjects: Entisols; Erodibility; Erosivity; Inceptisols; Landsat 8; NDVI; Landsat 8; Erodibility; NDVI; Inceptisols; Erosivity; Entisols
• ISSN: 2352-0094; 2352-0094
• DOI: 10.1016/j.geodrs.2017.06.003

Soil loss is a major cause of land degradation worldwide, especially in large areas of arid and semi-arid regions. With advent of new software and technologies such as remote sensing (RS) and GIS, there is a necessity to integrate them to achieve important information in a faster manner. The aims of present study were to evaluate soil erodibility (K-factor) using standard plots under natural rainfall and prediction of soil loss by integrating RUSLE, GIS and RS in Fars Iran. The RUSLE factors were evaluated as following: the R-factor was calculated using modified Fournier index; K-factor was measured in the field using erosion plots and estimated by the USLE equation; the C-factor map was created using the NDVI; the LS-factor map was generated from digital elevation model with 10m resolution, and the P-factor map was assumed as 1. Spatial distribution of annual soil loss in the Simakan watershed was obtained by multiplying these factors in GIS. The average of the measured K was 0.014thMJ−1mm−1 and 2.08 times less than the average of the estimated K (0.030thMJ−1mm−1). The performance of RUSLE was highly influenced by the K, because the annual soil loss predicted using estimated K (11.0th−1ya−1) was about twice as much as the measured K (5.7th−1ya−1). The spatial distribution of soil loss classes predicted was: 73.64% very low, 14.79% low, 10.19% moderate and 1.25% severe. Areas of severe soil loss are situated in the northern portion of the study area, which needs suitable conservation practices. •We Measured the K-factor in field using erosion plots under in calcareous soil.•The average value of predicted K by the USLE was 2.03 more than real K.•CaCO3 markedly decreased K due to significant correlation of −0.52 with K.•Soil loss for 73.64% areas was lower than acceptable tolerance (12th−1ya1).