Fig. 5

PCA ordination analysis and projection of variables (physicochemical parameters and cyanobacteria taxa) and sampling sites (in blue) on the factoriel level (1 × 2). The PCA ordinations were constructed from a distance matrix of environmental variables. The visually categorized 3 groups in the PCA plot based on the arrow direction and the geometric angles between them (the more variables are correlated, the more their arrows point in the same direction; thus, the correlation coefficient is symbolized by the geometric angles between the arrow). Circles show selected groups. Species abbreviations are given in Table 3