Hydrological and sediment dynamics within a small catchment with badland areas

Abstract

Badlands are the main sediment source areas affecting the headwaters of the Gállego and Aragón rivers in the Central Spanish Pyrenees. These morphologies characterise the landscape of the Inner Depression, occupying about 15 km2, which represent more than 2.5 % of the Inner Depression, and their occurrence is mainly associated to marly outcrops. Beguería (2005) suggested that Eocene Marls are the main sediment source in the Central Spanish Pyrenees, since this lithology is very sensitive to weathering and erosion processes. Previous studies showed that the hydrological response and sediment yield in mountain humid badland areas are highly seasonal and are mainly controlled by regolith development (Regüés and Gallart, 2004). Moreover, rainfall intensity and rainfall depth are considered to be the most important factors in determining the hydrological and sediment response in badland areas (Mathys et al., 2005). The aim of this work is to study the hydrological and sediment dynamics in a small catchment with badland areas by exploring the temporal variability of the hydrological and sedimentological response, and the relationships between hydrological and sedimentological variables.