Avaliação do regime de chuvas e do potencial de erosividade da Bacia do Carão, Ceará

Abstract

Precipitation is an important factor for the soil erosion process. The objective of this work was to evaluate the pluviographic regime of the Carão basin, located in the municipality of Tamboril, Ceará, correcting possible rainfall data and calculating rainfall erosivity in the region. For the calculation of the average rainfall, the daily average data of six pluviometric stations were used, according to table 1, with the temporal segment from 2003 to 2007, obtained from FUNCEME and ANA. For the calculation of the monthly and annual average precipitation of the basin, the Thiessen polygons method was adopted. For the calculation of rainfall erosivity factor (R), the equation adapted from Silva (2001) was used. The pluviographic regime of the Carão basin has a similar behavior in comparison to the other state basins, with intense and irregular rains mainly accumulated in the months of February, March and April. The rainfall erosivity factor was 8109.3 MJ.mm.ha-1.hr-1 per year. The rainfall erosivity of the basin is high compared to other basins in the south of the state, so it is important to have a proper use and management of the soil to mitigate the erosive potential of rainfall.