The work carried out by 3edata to develop tools for monitoring aquatic ecosystems using remote sensing has recently been published in the journal of international impact “Remote Sensing” (Access to article: https://www.mdpi.com/2072-4292/12/9/1514), in collaboration with researchers from the University of Santiago de Compostela, University of A Coruña and UNED. Part of these developments have been carried out in the framework of a Collaboration Project with the EMALCSA-UDC Chair.
The article published in “Remote Sensing” describes the modelling techniques developed by 3edata for water quality monitoring by combining data acquired by remote sensors.
This work has combined multispectral images obtained with 3 sensors on board 4 platforms (satellites and UAVs (drones)) with different spatial and temporal resolution. The tool generated is focused on the monitoring of eutrophication in reservoirs and inland water bodies.
The objective of the work, led by Dra. Carmen Cillero, was to evaluate the performance of a multi-platform approach for monitoring the trophic status of small and medium sized reservoirs with images obtained with multispectral sensors on board Sentinel 2 (S2A and S2B), Landsat 8 (L8) and UAV. The combined use of three different sensors (Multispectral Instrument (MSI), Operational Land Imager (OLI) and Rededge Micasense) was evaluated to obtain the concentration of the pigment chlorophyll a (chl-a), as a quantitative descriptor of the phytoplankton biomass and the trophic level of the water body.
The study was carried out in a system affected by cyanobacterial blooms, one of the most important human health risks derived from eutrophication. Different models were developed and tested, the most successful being those using combinations of red and near-infrared (NIR) spectral bands, although the blue and green bands were useful for classifying UAV images into chl-a ranges. The results show consistency between the three sensors at different spatial resolutions (10 m, 30 m and 8 cm), indicating a high potential for the development of a multi-platform and multi-sensor approach for monitoring the eutrophication of water bodies remotely.
The possibility of obtaining spatially explicit information on chl-a concentration on a regular basis is of particular help in the management of water bodies, especially those which use includes drinking water supply or bathing: as well as for assessing water quality within the needs and requirements of current monitoring programmes for the Water Framework Directive.