Nonmetric multidimensional scaling ordination diagram of sites based on Bray–Curtis similarity in diatom composition in spring, summer and autumn.

Average within group dissimilarity spring: 0.77 (grey squares); summer: 0.83 (open circles); autumn: 0.81 (black circles). The results of the statistical tests of community structure are visible in the graph: the groups differed in their relative position (centroids–PERMANOVA test) and not in the dispersion of the sampling points. (Stress = 0.25).