ESTIMATIVA DE PERDAS DE SOLO POR EROSÃO EM PROPRIEDADES RURAIS REGISTRADAS NO CADASTRO AMBIENTAL RURAL NO MUNICÍPIO DE ALAGOA NOVA-PB

Abstract

The intense population increase suggests that food production should be increased every day, which directly leads to the degradation of environmental resources such as soil. Quantifying, or at least estimating, the rate at which this environmental resource is being degraded is essential to diagnose degradation. The use of geotechnologies regulated by law, such as the GIS and the Rural Environmental Cadastre (CAR) database, which, coupled with the methodology of the Universal Soil Loss Equation (EUPS) estimation, is a instrument in the prediction erosion. The objective of this study was to estimate the loss of soils in rural properties registered in the rural environmental registry in the city of Alagoa Nova-PB, according to the existing soil classes. The USLE model was used to estimate the quantity of soil loss for each soil class and for the entire area of the municipality of Alagoa Nova, Paraíba, Brazil. The value of the R factor used was 6394.43 MJ.mm/ha.h/year for all areas and soil classes; the factor K used was the table for each soil class; the topographic factor (LS) was calculated according to slope and ramp length in the farms using a Digital Elevation Model; and the CP value used was assigned to the use and occupation of the soil, according to values available in the literature. Soil losses were estimated for the Red Argisol as 441.68 t/ha/year and as 298.84 t/ha/year for the Regolitic Neosol, both with erosion rate classified as Very Strong. The soils Yellow Red Argissol (126.11 t/ha/year) and Fluvic Neosol (187.53 t/ha/year) were classified with a Strong erosion rate. The values of soil losses verified for all soil classes exceed the tolerance limit of soil losses.