CONDICIONAMENTO DA LITOLOGIA NA COBERTURA E USO DA TERRA POR MEIO DE ÍNDICE ESPECTRAL (NDVI) DERIVADO DE SENSORES ORBITAIS

Conditioning lithology and land cover and land use by means of a spectral index (NDVI) derived from orbital sensors

Abstract

Although the remarkable correlation between vegetation and geology, this relationship is not quantified, being only empirical knowledge. This paper presents a correlation between the vegetative vigor of the three Bahia’s biome and the type of lithology where the vegetation develops. Vegetative vigor is measured using the Normalized Difference Vegetation Index (NDVI). NDVI was correlated with lithology through visual analysis and statistics mean, minimums and maximums. For that, three areas, of 100x100 km, one over each biome in Bahia were defined. The objects of study were images from the Operational Land Imager (OLI) sensor of the Landsat-8 satellite and data from the geological mapping of Brazil. As a result, the relationship between vegetation and geology has been better defined in the Cerrado biome, where vegetation has greater vigor over conglomerates and sandstones, lateritic-ferruginous sedimentary deposits and shale, with NDVI’s mean 0.61, 0.58 and 0.55, respectively. In the Caatinga, the vegetative vigor was more expressive on arcosean sandstone (with NDVI’ mean 0.79), stromatolitic limestone and metarenites with polymitic conglomerate, both with NDVI’s mean 0.65. In the Mata Atlântica, the focus was on metamorphic rocks, where NDVI’s means was around 0.72.