An investigation into the particle volume scattering function variability in a cascading reservoir system

Abstract

This work analyzed the spectral and spatial distribution of the particle volume scattering function, βp, in a cascading reservoir system. During fieldworks water quality parameters and scattering data were sampled in a predetermined stations. The βp was estimated using the ECO-BB9 equipment that measures the volume scattering function, β at 117° [β(117°)]. The estimated βp(117°) were compared with the remote sensing reflectance, Rrs, and the chlorophyll-a (Chl-a) concentration, total suspended matter (TSM) concentration and the transparency (measured using a Secch disk). The results showed that in a hypertrophic environment the βp is dominated by the phytoplankton scattering and in an oligotrophic water system, the scattering by a suspended matter dominates. The βp(117°) variability from a hypertrophic to an oligotrophic aquatic system affects the remote sensing reflectance (Rrs) spectral shape. Due to this, the parametrization of a unique bio-optical model to estimate the optically active components in the water will be challenging.