Responde of badland surfaces in South East Spain to simulated rainfall

Abstract

Field experiments using a sprinkler type rainfall simulator have been carried out on a variety of badland surfaces in SE Spain in order to establish their response patterns. Nine sites were selected between Valencia and Almería to represent the badland prone lithologies of this region. The hydrological response shows rapid runoff creating four main types of hydrograph. The major factors controlling infiltration and runoff and therefore hydrograph form relate to surface properties such as the presence of particular lichens and the cracking/swelling properties of the material. The erosional response demonstrates the overwhelming importance of cover by lichen plants or stones in reducing erosion rates. On sites with less than 20% cover erosion rates reflect material properties; high rates occur where the regolith is thin an with fine cracks the close rapidly when wetted.