RAINFALL EROSIVITY IN THE DESERTIFICATION NUCLEUS OF CARIRI AND SERIDÓ DA PARAIBA

Abstract

Desertification is a process of land degradation and occurs predominantly in arid, semi-arid and dry sub-humid areas. In view of this, we sought to determine the main characteristics of rainfall erosivity in the desertification nuclei of Cariri (Cabaceiras) and Seridó (Santa Luzia) in Paraiba, located in the intermediate geographic regions of Campina Grande and Patos, with these determinations being the main objectives. Using monthly and hourly rainfall data, collected from automatic meteorological stations, from these locations, the rainfall erosivity (EI), the kinetic energy of the maximum intensity of the rain, in 30 minutes (EI30), the number of events with Imax and the relationships between the averages of total rainfall >100 mm and the EIs. The main results show that, in deforested areas, the erosivity of the rain potentiates the erosion process and the interstate desertification nuclei have different characteristics of rainfall regime and EI. The maximum EI30 occurred in the late afternoon/early evening, with lower values in Cabaceiras, where most classes were low. In Santa Luzia, 1/3 of the classes were high to very high, although predatory anthropic interventions contribute to aggravating them.