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Abstract The purpose of this paper is to give an ecological description of the vegetation of the Jurisdam-Seekoegat section of the Mountain Zebra National Park in the Eastern Cape Province, South Africa. The effect of different land use practices on the vegetation composition was also investigated. Vegetation classifications and descriptions are of immense value to scientists and land managers and provide information on the composition, structure, diversity and effect of management on the different ecosystems present. The Braun-Blanquet approach was used to classify the different plant communities, while the veld condition was determined using the Ecological Index Method. Plant community data was analysed using the JUICE software package while diversity of the different plant communities was determined using the Shannon–Wiener and Gini–Simpson Indices. From a TWINSPAN analysis eight plant communities that can be grouped into six major communities were identified. Two plant communities not previously described for the Park were identified. The different plant communities can all be related to topography and effect of previous land use. Grasses and dwarf shrubs are the most prominent species. The plant communities of the rocky midslope areas achieved the highest species richness and diversity for the study area. The areas least affected by heavy grazing had a higher veld condition score than those heavily grazed by domestic animals in the past. The results of this study also emphasises the importance of resting overgrazed veld, while it seems that heavily grazed areas will not recover without further human intervention. A vegetation map of the different plant communities was produced using ArcGIS. Highlights • Vegetation classification improves our knowledge and understanding of complex ecosystems. • Rocky hilly areas act as refuge areas for vegetation with the highest diversity of plant species. • Resting of overgrazed veld in arid areas assists in veld condition recovery. • Wildlife has less of an impact on veld condition than domestic animals with continued grazing. • Overgrazing seems to alter nutrient structure of soil thereby altering vegetation composition. [ABSTRACT FROM AUTHOR]

Knowledge and understanding of wetland vegetation is an important component of sound wetland ecosystem management as vegetation represents a link between biota and ecosystem processes. In this paper, the saline wetlands of the arid inland regions of South Africa are discussed. Even though these wetlands contain water only occasionally they are among the largest wetland ecosystems in the country and their ecosystem processes are mostly determined by hydrological processes and particularly clay and salt deposition. These wetlands are dominated by three different groups of plants: salt-tolerant lawn grasses, sedges (occasionally) or halophytic shrubs. A subset of data from the South African National Wetland Vegetation Database, representing these vegetation types was used for analysis by means of clustering and ordination techniques. Twenty-nine saline wetland communities are described and these are further summarized into 15 community groups. Of the environmental variables used to explain the variation in the vegetation patterns, wetness appears to have the most important effect as it is also negatively correlated with electrical conductivity. Among the cations, it is sodium that has the greatest influence on species composition. Most of the types of saline wetlands are restricted to the Northern Cape and Free State Provinces, but plots with salt-tolerant grasses are found in all provinces except Gauteng. [ABSTRACT FROM AUTHOR]

This paper describes grass lawn wetlands, which are wetlands subjected to dynamic conditions, particularly highly fluctuating water tables that regularly drop deep below the ground surface. This occurs mostly in floodplain wetlands, as well as in wetlands in semi-arid regions or coastal plains. These wetlands are often dominated by short lawn grasses, particularly Cynodon dactylon , while other life forms, from taller tufted sedges to trees and shrubs, occur less frequently. A subset of data from a nationwide survey of wetland vegetation representing these grass lawn wetlands was selected for analysis using clustering and ordination techniques. Thirty-seven wetland communities are described and are further summarized into 13 community groups. Wetland communities on the coastal plains were associated with sandy soils whereas most of the other communities had a high clay fraction. Grass lawn wetlands are commonly found in a zone along the central, semi-arid part of the country and for this reason will likely play an important role in wetland monitoring in the long term. [ABSTRACT FROM AUTHOR]

Received 2 July 1999; revised 5 October 1999The aim of this paper is to identify, classify and describe plant communities on abandoned, formerly cultivated, old fields in the former Transkei (Eastern Cape Province) and to derive hypothetical succession pathways. Forty two releves, made in representative areas with abundant old-field lots, were classified and ordinated using standard methods of numerical vegetation data analysis. Three new associations were recognised, namely the Richardio brasiliensis-Eragrostietum planae, the Trichoneuro grandiglumis-Aristidetum congestae and the Tageto minutae-Cynodontetum dactyli. Within the Tageto minutae-Cynodontetum dactyli, two new sub-associations were recognised, namely cyperetosum esculenti and typicum. The most important coenocline spanning the young Tageto minutae-Cynodontetum dactyli and the old Richardio brasiliensis-Eragrostietum planae, correlated with the age of old-fields. We postulate that this coenocline might represent the main succession trend within the mesic old fields in Transkei. The Trichoneuro grandiglumis-Aristidetum congestae characteristic of dry sandy soils does not participate in this cline.Keywords: abandoned land, associations, ordination, plant communities, succession syntaxa. [ABSTRACT FROM AUTHOR]