The vegetation of the Karoo Nature Reserve, Cape Province. I. A phytosociological reconnaissance

A phytosociological survey according to the approach and methods of the Zürich–Montpeillier school was carried out on the Karoo Nature Reserve, Graaff-Reinet, South Africa. The study area is 160km2 in extent, and climatically it falls within the semi-arid zone. The complex climatological, geological, soil, vegetation and land-use gradients are emphasized. Eleven natural plant communities are recognized, reflecting a gradient from the warm, xeric conditions of the pediments to the cool, mesic conditions of the mountain ridges and plateaux. An hierarchical classification of the communities has been prepared, with the first division, corresponding roughly to the level of order, dividing the vegetation into Shrubland, Succulent Thicket and Dwarf Shrubland. The Shrubland is further divided into Open Shrubland on rocky slopes, Open Shrubland on dolerite upland and Grassy Open Shrubland. The Dwarf Shrubland is divided into grassy, succulent and degraded forms