Remote sensing techniques and tools to map marine bioindicators and their potential responses to anthropogenic pollutants: SPECTRAL SIGNATURES OF POSIDONIA OCEANICA AND CYSTOSEIRA SP. AND FIRST RESULTS

The ASI-STOPP project, aims to study marine bioindicators using new aerial platforms (HAA), equipped with multispectral sensors, able to remain in flight in the stratosphere for several months, allowing the study of anthropogenic pollution events on mesoscale (space and time) with high resolution, precision, cost-effective and practically.

 

In this context, to validate the data recorded by the sensors placed on the High Altitude Airships ad hoc measurement protocols must be drawn up and calibration tests must be carried out in the laboratory on the target bioindicators (algal and marine plant species) present in the areas of interest.

 

The first activities carried out concerned (i) the identification of the coastal target species present in the study areas of the project (e.g., Posidonia oceanica and Cystoseira sp.) fundamental for marine ecosystems to which they provide food, shelter for marine life, and oxygen; (ii) the selection of environmental specific pollutants (e.g., Chromium) that could affect algal and plants well-being.

A literature study and review of the spectral responses of the selected species have been carried out, which allowed us to build a summary table including all the methodologies applied in this research field. This work allows us to select the most suitable measurement protocol for our experiments.

In situ sampling was carried out and marine algal and plant species were transported to the laboratory for subsequent experiments, following the standard procedure reported in the literature to guarantee their adaptation and prevent samples. Finally, the spectral response of the selected species to the Chromium was assessed, according to the drafted measurement protocol and referring to the technical specifications of the Stellarnet Spectrometer. Spectral signatures of the selected species and data acquired were then compared with those obtained from the Cr pollutant enrichment experiments performed in the laboratory.