THE DE PLOEY EROSIONAL SUSCEPTIBILITY MODEL FOR CATCHMENTS, E(S)

This article is based on an unpublished manuscript by the late Prof. D r. Jan De Ploey. It focusses on the erosional susceptibility of catchm ents in terms of total energy input by the meteorological factors wate r and wind (E(S)-model).The form and the universal character of the ba sic expression of the erosional susceptibility are explained. Applicat ions of the model are illustrated for different processes such as land sliding and debris flows, gullying, creep, and rill-interill combinati ons. Characteristic E(S)-values exist for these processes. Also, E(S)- values vary in regions with differing pedo-botanical characteristics a nd land-use. The difference between E(S)-values for single storm event s and longer periods are related to the magnitude-frequency distributi on of erosive activities and allow in many cases an assessment of the age of erosion phenomena and an estimation of the recurrence period of extreme single events.