Raised Bogs in Eastern North America--Regional Controls for Species Richness and Floristic Assemblages

The vascular flora of 65 raised bogs was determined across climatic gradients in eastem North America. The major geographic patterns in species richness and floristic composition were analysed using linear regression, detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA). The vascular bog flora consists of 81 species in this region. Four major floristic regions distinguished by DCA correspond to the geographic zonation of bog land- forms. Each of these floristic regions is characterized by a different mean value for species richness. Raised bogs in the southern-continental floristic region (I) contain fewer than 20 species and have the most impoverished vascular floras in eastern North America (...)