Fig. 2From: Microscopic species make the diversity: a checklist of marine flora and fauna around the Island of Sylt in the North SeaPhytoplankton species richness in the Sylt Roads time series. Mean number of species per weekly sample ± standard error for entire years (annual mean) and single seasons. The R2 in spring refers to a linear regression and the arrows indicate low values after strong ice wintersBack to article page