Fig. 3.

The PCA results showing contribution of main environmental variables to ecological niche dimensions of the bloom-forming dinoflagellates Amphidinium crassum, Ceratium fusus, C. tripos and Prorocentrum micans in the Baltic coastal waters: T – temperature above pycnocline (°C), Sal – salinity above pycnocline, Zeu – Secchi depth, Chla – chlorophyll a, TN – total nitrogen, DIN – dissolved inorganic nitrogen, TP – total phosphorus, pH, NO₂⁻, NO₃⁻, NH₄⁺, PO₄³⁻, and SiO₄⁴⁻ (nutrient concentrations are measured in μmol L⁻¹).