ANÁLISE DA ALTERAÇÃO DE USO E COBERTURA DO SOLO NA BACIA DO RIO GUALAXO DO NORTE-MG ATRAVÉS DA COMPARAÇÃO DE DUAS TÉCNICAS DO SENSORIAMENTO REMOTO

Abstract

The main objective of this paper is quantifying and qualifying through the use of different tools of the remote sensing changes occurred in the Gualaxo do Norte river basin before and after the rupture of the Fundão dam in 2015 - MG. Images from the Landsat-8 satellite were processed in SPRING software. Two techniques were initially performed: Pan-sharpening and Principal Component Analysis (PCA). Subsequently, a supervised classification was executed in the two sets of images obtained so that the processes performed were compared and the best mapping of land cover and use was selected. Throughout the Gualaxo do Norte river it was verified suppression of the ciliary vegetation or other surface coverings that were next to the water courses affected by the sediments originating from the rupture of the dam. From the results obtained it is possible to consider that the spectral improvement obtained with the PCA allowed highlighting the areas directly affected by the sediments coming from the rupture. The images with 15m of spatial resolution obtained from the pan-sharpening allowed better recognition of different targets in smaller areas. Thus, the classifications performed with pan-sharpening images allowed better visualization of the targets due to the improvement in spatial resolution.