Fig. 4

Polychaete density, species richness, and diversity (H′) per quadrat for the different semiquantitative levels of substrate inclination. Uppercase letters refer to median values arranged in descending order. Groups of underlined letters indicate non-significant differences between pairs of means according to “a posteriori” Dunn’s tests following a significant Kruskal–Wallis ANOVA on ranks. For abbreviations, see Methods