Estimating total suspended matter using the particle backscattering coefficient: Results from the Itumbiara hydroelectric reservoir (Goiás State, Brazil)

Abstract

In this study, a quasi-analytical algorithm (QAA)-based model was parameterized using remote-sensing reflectance (Rrs, units in sr1), total absorption coefficient (at) and total suspended matter (TSM) concentration. The model was based on the particle backscattering at 561 nm (bbp(561)) and was derived from the QAA and TSM concentration. The aim of this work was to parameterize a QAA-based model to estimate the TSM concentration using the Landsat-8 Operational Land Imager (OLI) sensor in the Itumbiara hydroelectric reservoir, Brazil. The results demonstrated that the calibrated model, TSM = 0:907 + 5:479 × bbp(561) +, had a coefficient of determination of R2= 0.70 and that the validation had an R2= 0.82, RMSE = 41.39% and a mean bias of 0.074 mg l-1. The primary observation using the TSM and bbp(561) maps is that waters with lower bbp(561) values have lower TSM concentrations; there is a direct correlation between bbp(561) and TSM concentration.