Syntaxonomy and environmental gradients of the grasslands of the Stormberg / Drakensberg mountain region of the Eastern Cape, South Africa

A phytosociological classification of the grassland communities of the Stormberg / Drakensberg mountain chain and surrounding lowlands in the Eastern Cape is presented. The study area was firstly stratified on the basis of Acocks's (1988) Veld Types and then within Veld Types on local topography. An initial classification was derived by using two-way indicator species analysis (TWINSPAN) followed by table refinement according to the methods and techniques of the Braun-Blanquet school of phytosociology. Seven grassland associations and eleven sub-associations are formally described. Syntaxa are described using diagnostic floristic elements and characterised using habitat criteria. Annual rainfall and elevation related strongly to floristic gradients, and substrate and slope inclination accounted for local vegetation floristic and structural differences. Species richness was found to be highest in associations with high structural diversity and species turnover was strongest where environmental heterogeneity was high