Magnitud y frecuencia del transporte fluvial de sedimento en una cuenca mediterránea semihúmeda

Abstract

This study examines the magnitude and frequency of the sediment transport in the Arbúcies drainage basin (Catalan Coastal Ranges). For this purpose, daily discharges for the period 1967-1992 and sediment samples (including dissolved, suspended and bedload) obtained during 1991 and 1992 are taken into account Results indicate that dissolved load is more constant through time, while solid material transport is more dependent on flood events, especially those associated with bankfull discharges. Calculations show that sediment yield is dominated by events of high frequency and moderate magnitud associated with the bankfull discharge. Those events occur 2.2% of the time and carry 56% of the annual suspended sediment load and 31% of the annual bedload yield. Effective discharge for bedload transport in the Arbúcies river is, therefore, a relatively frequent flood event of identical magnitude to the bankfull (geomorphic dominant) discharge.