Fig. 5.

Correlations between occurrence of the bloom-forming dinoflagellates at different concentrations and the sizes of their ecological niches in the Baltic Sea. A, B: Dependence of the overall frequency of occurrence (Occurrence, n_tot) of dinoflagellates on their temperature-niche width, T (A), and total phosphorus-niche width, TP (B). Calculated using all cases in the entire database when the studied species were present in the samples. C, D: Dependence of the frequency of occurrence of the dinoflagellate species within their individual niche limits and the width of the respective niches, T (C), and TN (D). E, F: Correlation of the frequency of occurrence of the dinoflagellates at high biovolumes (BV > 0.12 mm³ L⁻¹), including blooms, and the width of their T niche (E) and TP niche (F). The inserted tables show the statistics (p < 0.05): n – number of occurrences of the dinoflagellates with the certain niche width of the measured parameter; m – slope; se – standard error; r2 – coefficient of determination (R²); F – the overall F-test; ss(reg) – the square sum of regression.