A long flume study of the dynamic factors affecting the resistance of a loamy soil to concentrated flow erosion

• Published in: Earth surface processes and landforms 1990-06, Vol.15 (4), p.313-328
• Main Authors: Govers, G., Everaert, W., Poesen, J., Rauws, G., De Ploey, J., Lautridou, J. P.
• Format: Article
• Language: English
• Subjects: Bgi / Prodig; Dynamic runoff erosion resistance; Earth sciences; Earth, ocean, space; Exact sciences and technology; Flume experiment; Geomorphology; Geomorphology, landform evolution; Loamy soils; Physical geography; Shear strength; Slopes; Surficial geology
• ISSN: 0197-9337; 1096-9837
• DOI: 10.1002/esp.3290150403

Experiments were carried out in a 20 m long flume to assess the variation of the runoff erosion resistance of a loamy soil as a function of initial moisture content and compaction. The results of seven experimental runs show that the runoff erosion resistance of a loamy material is extremely sensitive to variations in initial moisture content and, to a somewhat lesser extent, in bulk density. The very low resistance to runoff erosion of initially dry material is explained by structural changes which take place at the time of wetting: slaking and microfissuration cause a considerable decrease of the soil's shear strength and therefore of its resistance to runoff erosion. A first analysis shows that, during a given rainfall event, initially dry soils may well show significantly more erosion than initially wet soils, despite the increase of infiltration with decreasing initial moisture content.