Spatial distribution of morphodynamic characteristics of sandy beaches in the oceanic coast of Santa Catarina Island, SC, Brazil

Abstract

This work aims to analyze the spatial distribution of morphodynamic characteristics in headland-bay beaches located in the oceanic coast of Santa Catarina Island, SC, Brazil. The methodology consists in the compiling and in the grouping of data derived from the monitoring of beach profiles, using multivariate statistics techniques for a matrix of 40 cases (beach profiles) and 8 variables (morphometric parameters). Based on this matrix it was applied both a cluster analysis and a principal components analysis (PCA), using the minimum variance as a grouping strategy. The results show that these beaches may be divided in three groups: Group 1 - beaches of fine sand and lower hydrodynamic power; Group 2 - beaches of fine sand and moderate to higher hydrodynamic power; Group 3 - beaches of coarse sand and moderate to higher hydrodynamic power. These three groups were then related to a different morphodynamic stages in the surf zone, even having a high variability. Beaches of group 1 show mainly a reflective stage and the lower hydrodynamic power. Group 2 may show all intermediate stages as well as a dissipative stage. Group 3 may show an intermediate stage, but may also show characteristics of a reflective beach due to the slope of the beach face.