Evaluation of rainfall erosion index (R) in State of Piauí, Brazil

Abstract

The Rainfall Erosion Index (R) is the term of the Universal Soil Loss Equation that expresses the erosive capacity of the precipitation, which dissociates the soil particles by impact, leading to the impoverishment of the soil. Considering the importance of this factor, the present study aims to estimate the values of the Rainfall Erosion Index for the dry lands in Piauí - Brazil, identified according to UNEP (1991). In order to estimate the index we used the Bertoni and Lombardi Neto´s Method (1999). The results showed that the average annual value of the index was 5,153 MJ.mm/ha.h.year; the smallest value was 3,316 MJ.mm/ha.h.year and the highest one was 6,877 MJ.mm/ha.h.year.