Delving into the variations in tree species composition and richness across South American subtropical Atlantic and Pampean forests

We analyse here the variations in species composition and richness and the geographic ranges of the tree species occurring in south american subtropical atlantic and Pampean forests. our goals were to assess (i) the floristic consistency of usual classifications based on vegetation physiognomy, climate and elevation; (ii) the leading role of temperature-related variables on the variations in species composition and richness; (iii) the predominance of species with tropical-subtropical ranges, possibly as a result of forest expansion over grasslands after the last glacial maximum (lgm); (iv) the restriction of most subtropical endemics to stressful habitats as a possible result of past forest refuges during the lgm.