Inferência da profundidade da zona eufótica e do coeficiente vertical de atenuação de luz na água da Represa Mauá, Rio Tibagi/PR, a partir de Imagens Multiespectrais Landsat-8/OLI
Scientific researches focused on the water quality use, in general, empirical models of inference on water components from others observed in field, allowing a better spatial representation of the variable, beyond reduction of costs. Environmental researchers use the Secchi depth in indirect calculation of vertical attenuation coefficient for water irradiance and in the estimation of stretching euphotic zone to classify water types on Brazilian water ecosystems. Then, the main aim of this research was to realize the inference of water euphotic zone and the vertical attenuation coefficient for water irradiance in UHE Mauá/PR Reservoir, using the Landsat-8/OLI multispectral image, in spectral bands 1 (450-510 nm); 2 (530-590 nm); 3 (640-690 nm); 4 (850-880 nm) and 5 (1570-1650 nm) and spectral data collected “in situ”, and to generate an inference model of water transparence through available data. After adjustments and initial processing, the data were submitted to a correlation analysis, where there were found significant correlations 5% confidence level, not being raised the inference model. The data collected in situ sampling points, made it possible to estimate the vertical light attenuation coefficient in the water of the reservoir; classifying water as eutrophic; and estimate the depth of the photic zone, too narrow (between 2,29 m and 2,97 m). So concluded that the reservoir presents not much concentration of suspended solids and are in eutrophication.