PHYTOCLY Time Series Bay of Calvi Latitude:   42.5808     Longitude:   8.7285 Associated Investigators: Anne Goffart (nutrients, phytoplankton) , Amandine Collignon (zooplankton) ,   Jean-Henri Hecq (zooplankton)   The PHYTOCLY time-series, established in 1979 in the Bay of Calvi (Corsica, NW Mediterranean), aims to investigate the effects of climate forcing on surface nutrient replenishment as well on phyto- and zooplankton dynamics. The Bay of Calvi is a well-preserved and low-runoff system, with high water quality. It opens to the north to the Ligurian Sea and is characterized by a narrow continental shelf (mean width ~3 km) and the presence of a deep canyon (mean depth ~600 m), which enhances shelf-slope exchanges. The trophic character of the Bay of Calvi changes according to years, and ranges from very oligotrophic (low seasonal variability) to mesotrophic (well-marked increases in nutrient concentrations, Chlorophyll a and zooplankton during the winter-spring period). A third regime occurs during severe winters characterized by specific wind conditions when Mediterranean "high nutrient - low chlorophyll" conditions occurred. Sampling and analysis were supported by the University of Liege (Belgium), Stareso SA (Calvi, France), Ifremer (France), the French Water Agency (PACA-Corsica) and the Territorial Collectivity of Corsica.