Suspended sediment outputs from an abandoned farmland catchment, Central Spanish Pyrenees

Abstract

The temporal variability of suspended sediment outputs has been studied in the Arnás experimental catchment, Central Spanish Pyrenees. Relationships between peak flow and peak of suspended sediment concentration for floods is only high during the cold season. In summer the relationship is very poor, due to both the long separation between rainstorms. The so called rainstorm peak (the difference between peak flow and base flow) is the most important factor for explaining the variability of suspended sediment concentration, followed by the intensity of rainfall. Precipitation recorded the days before each flood only influences during the cold season. The prevailing positive hysteresis loops of the sediment concentration/discharge relationships during floods suggests that the main sediment sources are located in the channel and neighbouring areas.