Abstract:
This work tries to explore how the remote sensing could be used in monitoring of selected
water quality (WQ) parameters in small inland water bodies. The respective models to
estimate the water quality parameters were proposed based on the Landsat 7 ETM+ images
taken in 6 samplings from May 2012 to September 2014. The images used were scenes of
WRS-2, path and row 191/25, as well as 190/25, respectively. Samples were taken from
13 water bodies, from which 9 water bodies (20–90 Ha) were used in modelling (and some
removed due to clouds and imagery gaps). The WQ parameters were chlorophyll-a
(Chl-a), Total Carbon (TC), Total Organic Carbon (TOC), Total Nitrogen (TN),
Temperature (T), and Secchi Disk Depth (SDD). The 3 × 3 moving average-window
technique with a water-only-mask approach was used in order to limit the process toward
the water areas only. The best models based on the surface reflectance (T based on
brightness temperature [K]) showed a correlation r2 between 0.78 and 0.90 and NRMSE
between 16.6 % and 8.0 %, respectively, for all the water quality indicators. This has proved
that all the parameters can be remotely estimated. The models and workflow scheme
created are intended to help to institutions mandated in the monitoring of water bodies.
