Sentinel-2 como ferramenta de detecção de cianobactérias em açude de abastecimento

Abstract

One of the main problems faced currently in water bodies is the presence of cyanobacteria and cyanotoxins. Nutrient-rich environments promotes uncontrolled growth of these organisms, in events known as blooms. With the increase in frequency and intensity of blooms in eutrophic water bodies, the importance of monitoring and controlling cyanobacteria is increasingly evident. In this context, remote sensing, mainly via satellite, presents itself as a fast and inexpensive way of detecting these bloom events. The present study aims to analyze the effectiveness and efficiency of the implantation of a system to detect and quantify the presence of cyanobacteria using the parameter Chlorophyll-a, to determine cell density from optical properties and calibration of remote sensing algorithms by in situ data. The system, based on the Sentinel-2 satellites, presents good results for the determination of Chlorophylla, whereby the empirical model Stepwise 3B achieved the determination coefficient R² = 0,71. The cell density determination model SSa(665) presented low efficiency, explained by the technological incompatibility of the sensors installed on the satellite, but which nonetheless, allows a categorical analysis of the formation of blooms.