LINHAS ISOEROSIVAS DO ESTADO DE PERNAMBUCO - 1ª APROXIMAÇÃO

Abstract

Erosivity is the potential ability of rain to cause erosion on somewhere. With the objective of mapping the rainfall erosivity in the entire State of Pernambuco, the average monthly values of the EI30 index with were correlated with Fournier rainfall coefficient and the average monthly precipitation, as well as the yearly values of the index EI with average yearly precipitation values. Data from 11 localities representative of their distinct climatic regions were utilized. From the best regression equations found for each region, the average yearly values of the EI30 index were calculated ( Factor R of Universal Soil Loss Equation - USLE) for 96 localities in the State, based on periods of 14 to 75 years of rainfall records. The values of erosivity found varied from 1,500 to 10,000 (Mj mm ha-1 h-1 year-1), where the Zona da Mata, Agreste and Sertão regions presented a moderate erosive potential, with values from 1,500 to 3,500 (Mj mm ha-1 h-1 year-1). The litoral region, was characterized by high erosivity, with annual average values of the index EI bethween 5.500 to 10.000 (Mj mm ha-1 h-1 year-1).