Aspects of the syntaxonomy and synecology of the grasslands of southern KwaZulu-Natal

Abstract

The Grassland biome of South Africa is ofmajor importance to this country's agriculture, mining and conservation practices. The extent of urbanisation and economic activity within this biome has led to the destruction or alteration of large areas of it, and concerns over this have led to the formation of a Grasslands Biome Project. A primary objective of the project is to improve our understanding of the workings of grassland systems, so that land use planning and conservation practices can be facilitated. The identification and description of major vegetation types and subtypes in the grasslands of southern KwaZulu-Natal forms part ofthis study. A total of547 sample riots were randomly distributed over an area of 14 000 km 2 between Estcourt and the Eastern Cape border. Stratification was based on Turner's Physiographic Regions ( 1967), Phillips' Bioclimatic Subregions ( 1973 ), and terrain units. The vegetation was classified by means of TWINSP AN and Braun-Blanquet procedures. Altogether 27 plant communities and 41 sub-communities were identified, described phytosociologically and ecologically interpreted. The diversity of these grassland communities was compared to that of grasslands in other parts of the country, and their conservation status was assessed in terms of land utilisation, endemism and biodiversity.Die grasveldbioom van Suid-Mrika is van groot belang vir die land se mynbou, landbou en natuurbewaring. Verstedeliking en ekonomiese bedryf binne die bioom het tot die vernietiging of verandering van groot gedeeltes daarvan gelei, en bekommernis hieroor het tot die vorming van 'n Grasveldbioomprojek gelei. 'n Primere doel van die projek is om die mens se begrip van die funksionering van grasveldsisteme te verbeter, sodat landgebruikbeplanning en natuurbewaring kan geskied. Die identifikasie en beskrywing van hoof plantegroeitipes in die grasveld van suidelike KwaZulu-Natal vorm 'n deel van die huidige studie. 'n Totaal van 547 monsterpersele is ewekansig oor 'n gebied van 14 000 krn2 tussen Estcourt en die Ooskaap grens uitgeplaas. Stratifisering is gebaseer op Turner se Fisiografiese Eenhede (1967), Phillips se Bioklimatiese Subeenhede (1973), en terreineenhede. Die plantegroei is deur middel van TWINSPAN en Braun-Blanquet-prosedures geklassifiseer. 'n Totaal van 27 plantgemeenskappe en 41 subgemeenskappe is geidentifiseer, beskryf en ekologies gei:nterpreteer. Die diversiteit van hierdie grasveldgemeenskappe is vergelyk met die van grasvelde in ander dele van die land, en hulle bewaringsstatus is geanaliseer in terme van benutting, endemisme en biodiversitiet.