Seasonal morphodynamic classification of beaches in Necochea municipality, Buenos Aires Province, Argentina

Abstract

The seasonal morphodynamic classification of Necochea and Quequén beaches (Buenos Aires Province, Argentina) was determined. Based on 102 seasonal beach profiles and sediment sampling between February 2006 and December 2009, variations in morphology and sediment budgets of five beaches were studied. According to the dimensionless fall parameter and the relative tide range, the beaches were classified depending on their modal morphodynamic state. In Quequén, beaches presented intermediate and reflective states, whereas in Necochea they presented dissipative states. The Iribarren number showed that plunging and spilling breakers predominated in Quequén and Necochea, respectively. In winter, the beaches became more dissipative, while in summer-autumn they were more reflective. This general behavior agrees with the erosion/accretion cycles. Beach profile variability was higher in Quequén. These results have been used to elaborate the coastal management program of the area.