Using dendrogeomorphology to estimate soil erosion in mixed native species and pine forests on Ultisols in Piracicaba, Brazil

Abstract

This work aims to study and date the erosion process in a gully located at the Experimental Station of Tupi (Piracicaba, São Paulo, Brazil) using dendrogeomorphology. Dendrogeomorphology is a relatively new science that relates the growth of tree-rings with geomorphological processes allowing chronological reconstruction and occurrence of events. The relevance of this study is to know the potential of this science in tropical areas because currently this type of study is lacking in these areas. This technique was applied using exposed roots of species of Pinus ssp. The dating of the erosion process was based on the changes in the pattern of root growth, such as the width of the ring, eccentric growth, percentage of latewood and density of the wood that occur after exposure by erosion. Through the study of these changes the first year of root exposure was determined, and the annual rate of erosion was estimated. Erosion rates of 0.65 and 2.39 m/year were found, characterizing the longitudinal advancement of the gully. Finally, dendrogeomorphology demonstrates great potential as a tool in tropical areas. The data and information obtained can be translated into a dendrogeomorphological database and contribute to the expansion of this science in Brazil and areas of tropical environments.