Uso de sensoriamento remoto para mapeamento de áreas susceptíveis à desertificação na região Semiárida do Brasil

Abstract

Remote sensing was used to map and identify the state of degradation/desertification of the entire Brazilian semiarid region, where the susceptible to desertification areas (ASD) are located. For this purpose, it was used Landsat 8 imageries. This region can be characterized as an area of high environmental vulnerability, with the predominance of the semiarid climate, which registers a strong anthropic pressure on the natural resources. The ASD in question extends through the 9 states of the Northeast and further north of Minas Gerais and north of Espirito Santo, a region with high poverty rates. In order to identify the areas with evident signs of degradation, besides the interpretation criteria based on the texture, geometric form and spectral response of the imaged targets, it was also considered climate and socioeconomic information, land use, vegetation cover, environmental systems and soil maps. The results showed that 70,279.46 km² of this area are already heavily degradedfrom the physical point of view. It was also verified the efficiency of the Landsat 8 satellite images and the potential of the remote sensing technique in mapping of this layer, showing a high degree of reliability in the delimitation of the affected areas. From this study, it is evident the possibility of a periodical update and establishment of a monitoring plan for the degradation of dry lands in the Brazilian semi-arid region.