Fig. 4

Correspondence factor analysis, with projections of a variable (main contributor species) and the sampling site. F1 represents turbidity, from low (left) to high (right); F2 represents water mass stratification, from homogenous (negative) to highly stratified (positive). The contributions of these factors to inertia are shown in parentheses. The same numbers represent results from different years. Site typology was defined according to cluster analysis on abiotic parameters results (Fig. 2; Table 1)