Schematic representation of the partitioning of the Jaccard dissimilarity index into turnover and nestedness components (see text for the formula and more information). Turnover refers to the gain and loss of species (species replacement) between the areas (e.g. high dominance plots of a particular dominant species), whereas nestedness refers to the cases where the plot with the lowest number of species represents a subgroup of species of the richest plot/site. In the scheme, the species in blue are unique to plots A and C, the species in black are shared between both plots and the species in orange are unique to plot B.