<b>Rainfall erosivity factor of <em>Pedrinhas Paulista</em>, state of <em>São Paulo</em></b> - DOI: 10.4025/actasciagron.v25i1.2467

Abstract

Rainfall erosivity in Pedrinhas Paulista city was studied with the purpose of supporting its land use planning. Rainfall erosivity factor (R), used in the universal soil loss equation was calculated for a continuous raingauges series of 24 years of rainfall data. The computed value was 7670 MJ.mm/ha.h.y, which is expected to occur at least once every 2.33 years, with a probability of occurrence of 42.92%. The higher annual soil losses are expected to occur between the months of October and March, as shown by the 77.12% of the total annual erosivity for that period. The values of the EI₃₀ annual erosivity indexes, expected for the return periods of 2, 5, 10, 20, 50, and 100 years, were 7404, 8833, 9779, 10686, 11860 e 12740 MJ.mm/ha.h.y, respectively. The value of the maximum daily rainstorm, calculated for the return period of 10 years, was 144 mm. This datum could be used in the ideal transversal section calculation of the agricultural terracing channel.