Mapped tree species richness derived with equation (1).

Coloured circles, representing individual plots, vary in size according to observed tree species richness; large circles represent plots with high tree species richness (e.g., SR = 7 species per 0.1-ha plot) and small circles, low species richness (e.g., SR = 1 species per 0.1-ha plot). Plot tree-species dominance (accounting for ≥ 33% of all trees in a plot) is labelled according to colour (Fig. 4).