Comportamento Espectral da Cultura da Cana-de-Açúcar em Imagens de Satélite

Abstract

Brazil is the largest producer of sugar cane, having great relevance in the Brazilian agribusiness sector due to its high economic importance, due to the increase in global demand for ethanol and sugar consumption around the world. The Central-West region is the largest producer in the country and has great aptitude for cultivating the crop. The objective of this work was to evaluate the spectral signature of sugarcane crops, based on Cbers-4 and Landsat-8 images, and calculate vegetation indices. The coordinates (21º20’16’’S 54º25’41’’W) of a rural property were used, in the microregion of Nova Alvorada do Sul – Mato Grosso do Sul. Images were collected from November 2020 until the end of May 2021, obtained on the GloVis website managed by the United States Geological Survey (USGS), as well as on the Image Catalog website of the National Institute for Space Research (INPE) and on the Copernicus Open Access Hub website managed by the European Space Agency (ESA). The images were processed in the free software QGIS 3.16.4, where they were georeferenced in the Universal Transverse Mercator cartographic projection, DATUM - SIRGAS 2000, zone 21, Southern Hemisphere. The use of two satellites allowed a good visualization of the state of the crop, with the Cbers-4 satellite presenting better results with greater clarity and image quality. Among the indices evaluated, the GNDVI presented better results when compared to the NDVI, as it demonstrated greater clarity about the variations in vegetation compared to the results of the colored compositions.