Modelización en Geografía Física.-Erosion in a landscape evolution context: LISEM and LAPSUS

Abstract

ABSTRACT In many erosion studies only contemporary erosion is assessed, assuming this to be the direct or indirect effect of human influence. In geomorphological studies, erosion is viewed as a naturally occurring process in the context of landscape evolution. This study aims to bridge the gap between these contrasting views. In the study area (Guadalentin; SE Spain) two models are applied: the short-term, event-based model LISEM (Limburg Soil Erosion Model) and the long-term landscape evolution model LAPSUS (Landscape Process Modelling at Multi-Dimensions and Scales). LISEM needs relatively many and detailed input parameters and rainfall data. LAPSUS uses relatively simple process descriptions, input maps and average rainfall. Theoretically LISEM is expected to perform better than LAPSUS due to more detailed processes and input variables. However, spatial variability of the required characteristics is high in the study area, giving rise to high uncertainty in input and output. Therefore, LAPSUS may give better results despite the simpler process descriptions and input maps. Currently, this issue is being explored for the Guadalentin Basin on various spatial scales. Preliminary results will be presented when available. Eventually, we aim to combine the two models in a modelling framework adapted to the Guadalentin and assessing multiple scales