Gridded abundance maps of phytoplankton diversity and toxicity around the French coast

Gridded abundance maps representing Dinophysis species, phytoplankton taxon richness and algal toxicity along the French coast. This product was developed with DIVA (Data-Interpolating Variational Analysis). Data was provided by IFREMER (REPHY - réseau de surveillance du phytoplancton. Institut Français pour la Recherche et l'exploitation de la mer, Nantes, France.). Several Dinophysis species produce toxins and can cause gastrointestinal illness and Diarrhetic Shellfish Poisoning (DSP), even at low cell densities. A algal toxicity ratio was calculated by dividing the concentration of harmful planktonic cells by the sum of the harmful and the harmless species. Algal toxins from harmful algal blooms (HABs) can cause shellfish poisoning in humans and be of danger to live stocks in coastal water (Descriptor 5 Eutrophication). Phytoplankton organisms are responsible for about 45% of annual global photosynthesis. They are as such vital for the functioning of marine food webs (considered in MSFD descriptor 4) and are the main drivers of the global biogeochemical cycles.