CYCLIC VOLTAMMETRY ARRAY REQUIREMENTS TO CORRELATE SATELLITE OBSERVATIONS OF ALGAL BLOOM SEVERITY WITH BLOOM-GENERATED HYPOXIA

Rezumat

Aerial and spaceborne instruments have increased the ability to monitor algal blooms frequently and in large water bodies. But such remote sensing methods cannot inform about toxic outcomes of severe algal blooms such as hypoxia, ammonia, hydrogen sulphide and phycotoxins. We developed a robust and low-cost cyclic voltammetry multielectrode instrument (called SPEAR) for automated monitoring of redox parameters. This instrument produces information about the evolution of oxic/anoxic and oxic/sulphidic transition zones in the water/sediment column. We present requirements and calibration of a SPEAR64-based array with 300 m XY resolution, similar to the OLCI instruments from Sentinel-3 satellites. We discuss how SPEAR array results can enhance the interpretation of spectral-based algal blooms analyses, with regards to predicting hypoxia and hydrogen sulphide in water.