Vegetation ecology of the Southern Free State

This study forms an integral part of the main long-term goal to compile a . comprehensive synecological synthesis of the vegetation of the southern Free State. (1) to identify, classify and ecologically interpret the plant communities in the study area, (2) to compile a comprehensive phytosociologicaJ and synecological synthesis of the vegetation of the study area, including all the phytosociological data compiled by other researchers in the southern Free State, and (3) to take part in compiling a comprehensive synecological synthesis of the Grassland Biome. Relatively little is known about the vegetation of the study area. The main aim of the study was: The study area is situated in the southern Free State, covers approximately 27 000 km² and is bounded by latitude 29° South andlongitude 270 East. It is bounded by the Orange River in the south and by the imaginary boundary between the Free State and Northern Cape Province in the west. The aims were achieved through compiling extensive phytosociological surveys in the study area. The study area was stratified into relative homogeneous units of major attributes such as geology, topography (land form), physiognomy and dominant species. A phytosociological survey according to Braun-Blanquet procedures as weU as habitat analysis were being done. Data were being classified through the TWINSPAN program and then refined by Braun-Blanquet procedures. From the 2 370 relevés compiled in the southern Free State, 394 plant communities were identified, classified and ecologically interpreted. 16 Major vegetation units were described from the 394 described plant communities. An ordination algorithm (DECORANA) was used to indicate the floristic relationships among the vegetation units and make the classifications more interpretable. The synecological synthesis of the vegetation of the southern Free State plays an important role in compiling a comprehensive synecological and syntaxonomical synthesis of the vegetation of the Grassland Biome of southern Africa.