Distribuição, probabilidade de ocorrência e período de retorno dos índices de erosividade EI30 e KE>25 em Seropédica - RJ

Abstract

This work was carried out in order to study the distribution, the occurrence probability and the return period of the rainfall erosivity in Seropédica city, Rio de Janeiro State, Brazil. It was considered a continuous rain gauges series for the period from 1973 to 2002, and by using specific adjustment models for the region, it was determined the annual and monthly erosivity indexes EI 30 and KE>25. With the obtained results, it was possible to conclude that: a) the annual erosivity indexes values EI 30 and KE>25 were 5,960.4 MJ mm ha -1 h -1 and 99.2 MJ ha -1 , respectively, which was expected to occur at least once every 1.97 year, with an occurrence probability of 50.82%; and b) annual values EI 30 of 5,995; 7,262; 7,684; 7,895 8,022 and 8,064 MJ mm ha -1 h -1 and annual values KE>25 of 99.8; 122.7; 130.3; 134.1; 136.4 and 137.1 MJ ha -1 are expected at least once every 2; 5; 10; 20; 50 and 100 years, respectively.