The Republic of South Africa is situated at the southern tip of Africa. It is bordered to the north by Namibia, Botswana, Zimbabwe and Mozambique; in the west by the Atlantic Ocean and in the south and east by the Indian Ocean (Figure 1). The total land area is 1 223 201 sq km (excluding Lesotho and Swaziland).

Figure 1.South Africa, showing the position of its neighbours, enclaves, the boundaries of its nine provinces and the location of some important cities.

South Africa's population is estimated at 40.6 million (Stats SA 1996), of which approximately 46% is rural and 54% is urban. Agriculture accounts for 3.2% of GDP and 7% of exports (R14.57 billion in 2000; R1.00=US$0.12 in August 2001) and supports, directly or indirectly, 15% of the population (Department of Agriculture and Land Affairs 2001).

South Africa is a multi-cultural nation, with many ethnic groups and colonial nations represented in its populations. It is this wide variation in the origin of its people which make understanding the management of its natural resources so interesting. The remaining San people of the southern Kalahari represent the oldest traditional users of natural vegetation for survival. San people are still able to subsist as hunter gatherers in the most arid regions of the country, providing some evidence of how it is possible to sustain small human populations in this region. San exhibit a strong understanding of resource limitations and probably follow the principles embodied in the dis-equilibrium theory (Ellis & Swift 1988) the closest of all southern African people. The San were also able to remain in the mountainous regions of the Drakensberg and along the Great Escarpment. The evidence of their history is found in the numerous rock paintings and other artefacts which occur in caves along the Great Escarpment.

The Nguni people of the eastern seaboard are graziers with a long (10000 year) history of maintaining domestic livestock. These people comprise the Seswati, AmaZulu and AmaXhosa nations, and occupy the leasehold lands in Gazankulu, KwaZulu Natal, Transkei and Ciskei. The society is organized around a village, comprising dwelling units, cultivated lands and grazing lands. The early cattle were of the Bos indicus stock and this line is being developed and protected in recent years with the establishment of an Nguni stud book.

Europeans of Dutch descent arrived in South Africa in 1652, and settled at first at the supply station in Cape Town. These settlers where joined by French Huguenots, who brought with them a knowledge of viticulture and animal husbandry (mainly sheep).  Descendants of the early Dutch settlers began moving into the interior of the country with the abolition of slavery, and developed the extensive cattle and sheep farming enterprises which currently occupy land in the Kalahari, central Free State and the North West Province. It was only in 1820 that settlers of British origin arrived and settled on the eastern seaboard.  They developed mixed-farming operations in the Eastern Cape and Kwa-Zulu Natal, and included cattle and wool-sheep enterprises.

There are four broad categories of land tenure in South Africa. Approximately 70% of the country is so-called "commercial" farmland under freehold tenure, 14% is allocated to communal areas with leasehold tenure, 10% is formally conserved, and the remaining 6% is used for mining, urban and industrial development. The communal areas are situated mainly in former homelands of Transkei, Ciskei, Bophutatswana, Kwa-Zulu, Lebowa, Venda and Gazankulu in the north and east of the country, while the commercial areas occupy most of the west, centre and the south of the country.

In 2000, the greasy wool clip came to 52 671 t and South Africa produced 25% of Africa's wool crop. In 2000, the country's mutton production amounted to 114 000 t. The main breeds of sheep are fine-woolled Merino, the South African mutton Merino, Dohne Merino, Dormer, Dorper (the latter two are locally developed breeds) and the Karakul. The Karoo is one of the main sheep-farming areas in the country with the Karakul industry limited to the dry north-western regions of the Northern Cape Province. In 2000 the national herd was estimated at 28.6 million sheep.

South Africa's national commercial cattle herd is estimated at 13.5 million, including various international breeds of dairy and beef-cattle, as well as indigenous breeds such as the Afrikander and Nguni. Locally developed breeds include the Drakensberger and Bonsmara. These breeds are systematically and scientifically improved through breeding programmes, performance testing and the evaluation of functional efficiency. Almost 590 000 t of beef were produced in 2000. Owing to the relatively low carrying capacity on the natural pastures, extensive cattle-ranching is practised in the lower rainfall regions.

The rangeland resources of South Africa have been reported on extensively in the recent past, with three important publications having appeared (Cowling et al 1997, Dean & Milton 1999, Tainton 1999, Tainton 2000).  These publications provide exhaustive information on the types of rangeland resources, their general ecology, including plant species composition and associated environmental variables, and the productivity and management. In addition, information on the management of rangelands in southern Africa is provided in the approximately 960 research publications which have appeared in the African Journal of Range & Forage Science and is predecessors since 1966. Other journals which provide exhaustive information on the natural resources of South Africa include the South African Journal of Botany and Bothalia. South African range researchers are strongly encouraged to publish in the wider international literature, and many important research articles appear in peer-reviewed journals published on other continents. This chapter does not attempt to synthesize or review all this available information, but provides a brief summary of the current status of our understanding of southern African rangeland eco-systems.

2.1 Major topographic features
The Great Escarpment and the Drakensberg mountains provide the physical barriers which determine the climate and vegetation of much of the livestock growing regions of South Africa.  In geological time, several phases of uplifting, erosion and deposition have created complex landforms determined by the underlying geology.The country comprises five main physiographic regions (Figure 2). The first is the south western fold mountains, which influence the climate and vegetation patterns of the southern Cape. The second is the coastal plain, which extends from the Namibian border, all along the coast to southern Mozambique. This narrow plain between the ocean and the Great Escarpment is the region with the most fertile soils, moderate to high rainfall and where most intensive livestock production occurs. The Great Escarpment, which forms the major barrier to moisture reaching the interior, together with and the central highveld, contains most of the high elevation grasslands. The major urban, mining and agricultural activities take place in the central highveld, which is situated at 1600-1700m. The great karoo basin occurs from 1400-1600m and contains the steppe-type vegetation associated with fertile aridosols of the semi-arid region. The Kalahari region, bordering on Namibia and Botswana, represents a very important extensive livestock producing area. The region is the southern part of the continental scale basin which is covered by sands of varying depth (sometimes >200m). Deep boring technology has enabled commercial graziers to become permanently established in the region, and to optimise livestock production. The vegetation is an arid savanna, with a carrying capacity of 30-40 ha per LSU.

Figure 2. The elevation (m) for South Africa (Dent et al 1987).

2.2 Major soil types
The soils of South Africa have been classified using a hierarchical system (Soil Classification Working Group 1991), and include a large number of soil bodies which range from soil bodies black, smectitic clay on dolerite to yellow, kaolinitic clay on Beaufort sediments. The classification system contains two main levels, SOIL FORM and SOIL FAMILY. There are currently 73 SOIL FORMS, defined by the nature of the topsoil (organic, humic, vertic, melanic or orthic), and numerous diagnostic sub-soil horizons.

The relatively young South African and active geology has given rise to soils of high nutrient status. The Nama-karoo biome of the central regions comprise predominantly mudstones and sandstones of the Karoo Supergroup, which give rise to shallow (<30cm) aridosols, with a calcareous hardpan layer typically in the profile. During the Jurassic age, these sedimentary rocks were intruded by dolerites, which criss-cross the landscape in characteristic dykes. The dolerites contain plagioclase which give rise to soils of high clay content. These features contain many grasses and associated phreatic woody shrubs, and represent refugia for many desirable (to the herbivore) plant species. The dolerite sills and dykes provide summer grazing, whereas the nutrient rich calcareous plains provide abundant, high quality winter forage. The grasslands of the highveld are associated with high nutrient status soils of basalt and dolerite origin.

The savannas of the Mpumalanga Lowveld are associated with the gabbros and granities of the Bushveld igneous complex.  The latter give rise to sandy soils of moderate nutrient status. The gabbros give rise to a nutrient rich Mispah rock complex.

In geological time several phases of uplifting, erosion and deposition have created complex landforms determined by the underlying geology. The Cape Fold Mountains and the Lesotho Highlands are the largest surfaces which intrude above the African plane. The Cape Fold Mountains are siliceous rocks, giving rise to immature, litholic soils. The Lesotho Highlands on the other hand are basaltic, giving rise to mollisols (Partridge 1997). The grasslands of the highveld are associated with high nutrient status soils of basalt and andesitic origin.

3.1 Climate and drought
With a mean annual rainfall of approximately 450 mm, South Africa is regarded as semi-arid. There is, however, wide regional variation in annual rainfall (Figure 3), from less than 50 mm in the Richtersveld on the border with Namibia, to more than 3000 mm in the mountains of the south western Cape, however only 28% of the country receives more than 600 mm (Table 1). The uncertainty of the rainfall is best expressed by the co-efficient of variation in annual rainfall (Figure 4). The low rainfall regions have the highest co-efficient of variation. Annual rainfall distribution is skewed such that there are more below average than above average rainfall years, and the median is a more meaningful than the mean. The high seasonal variations are accompanied by high spatial variability, and the annual potential evapo-transpiration may exceed annual precipitation by ratios of up to 20:1, hence drought conditions are a common phenomenon (Schulze 1997). The declaration of drought status to a magisterial district has historically been used by the Department of Agriculture & Land Affairs to intervene in exceptional circumstances. Since 1994 this intervention has been discontinued and graziers are encouraged to plan their production system within the long-term production expectations of their farms.

Table 1. Annual rainfall distribution and climatic classification in South Africa

Source: Schulze 1997

Figure 3. The median annual rainfall for South Africa (Dent et al 1987).

Figure 4. The co-efficient of variation in annual rainfall for South Africa. Derived from the long-term rainfall records (50 years or more data) from 1015 stations.

Seasonality of rainfall
There are three major zones within the country, namely the winter rainfall region of the western, south western and southern Cape; the bimodal rainfall region of the Eastern Cape, and the strong summer seasonality of the central highveld and KwaZulu Natal. The regions with strong summer seasonality are strongly influenced by the inter-tropical convergence which moves southwards during the southern hemisphere summer. The season of rainfall in the south western and southern coastal regions is influenced by the frontal systems developing in the southern Oceans. These frontal systems bring cool, moist air during the winter season (June - August), and promote the development of sclerophyllous and succulent floras. In general, the natural vegetation of these regions is less useful for livestock production. Because of the varying rainfall seasonality, growing periods vary throughout the country. In the north, east and along the coastal belt, summer seasonality encourages C4 grass production and the main focus is cattle and sheep production. In the semi-arid central and western regions C3 grasses and shrubs predominate, and this favours sheep and goat production.

Temperatures
The temperatures in South Africa are strongly determined by elevation and distance from the sea. The high elevation (1500-1700m) inland regions experience warm summer (January) mean daily maximum temperatures (26-28^oC) and cool winter (July) mean daily minima (0-2 ^oC), with frost during the coolest months (Schulze 1997) . These regions experience occasional snow. The warm Mozambique current on the east coast plays a strong role in ameliorating temperatures along the coastal zone between East London and Mozambique. The northern parts of the coastal zone experience warm winter daily minima (8-10 ^oC) and warm summer maxima (32 ^oC), and the climate is strongly sub-tropical. The vast interior, represented by the Kalahari basin and the Nama-karoo, experiences a more extreme climate, with low winter mean daily minima (0-2 ^oC ) and high mean daily summer maxima (32-34^oC). The southern and south-western coastal zone experiences moderate winter mean daily minima (6-8 ^oC ) as a result of the circum-polar westerlies which bring moist, cold air from the southern oceans during June, July and August. The temperatures on the west coast, from Cape Town to Port Nolloth, are influenced by the cold Benghuella current. This arid regions experiences July mean daily minima of 6-8 ^oC, but little or no frost, and is able to support a rich succulent flora. The cold ocean current favours the development of fog during the winter months, bringing cold, moist air onto coastal plain.

3.2 Agro-ecological zones and biomes
Based on bio-climatic and growth form information, Rutherford & Westfall (1986) defined six biomes in South Africa. An improvement has been suggested by Low & Rebelo (1996), who further sub-divided the savanna biome to include the category "Thicket" which occurs predominantly in the river valleys of the eastern and south eastern coastal region (Figure 5).

Figure 5. The biomes of South Africa (After Rutherford & Westfall, 1986 and Low & Rebelo, 1996).

Succulent Karoo
The succulent karoo biome occurs in the winter rainfall regions of the southern and south-western portions of South Africa. The flora of the biome comprises mainly of shrubs (0.5-1.5m) and dwarf shrubs (<0.5m) with succulent leaves and stems. The climate of the region is arid to semi-arid (100-250mm per annum), with a strong winter seasonality. The succulent karoo is well known for its high floristic diversity, part of which is a function of its proximity to the floristically rich adjacent fynbos biome. The biome, with >5000 species in 100 251km², has the highest species richness recorded for semi-arid vegetation, and more than 50% of the plant species are endemic to this biome (Milton et al 1997). Some of the areas with high floristic diversity (e.g Richtersveld and Namaqualand) receive a large portion of their precipitation in the form of coastal advective fog during the coolest months of the year. There are many species in two families (i.e. Mesembryanthecaceae and Crassulaceae), several unique taxa (species of  the genus Pachypodium) and growth forms (leaf and stem succulents). This diversity has made the biome ideal for the development of an eco-tourism industry which promotes the floristic uniqueness of the region. The biome is an important small stock region, where graziers focus on the production of mutton sheep, goats and ostriches.

Nama-karoo
The Nama-karoo biome is the largest of the biomes in South Africa, comprising much of the central and western regions of the country. The biome is dominated by a steppe type vegetation, comprising a mixture of shrubs, dwarf shrubs, and annual and perennial grasses. The biome is associated with the moderate rainfall regions (250-450mm per annum) and is ideal for sheep and goat production. The summer seasonality of the rainfall in the eastern parts of the biome means that there is often abundant grass production during the growing season. Graziers are able to optimize production during this time. In the winter months, the dwarf shrubs maintain their crude protein at around 8%, providing excellent forage. The nutrient-rich substrata provided by the mudstones, sandstones and dolerites mean that this production is sustainable. There were earlier suggestions that large scale structural transformations were taking place in this biome (Acocks 1964), with the dwarf shrubs supposedly spreading into the adjoining grasslands of the central Free State. This process has not continued in the way envisaged, and the relatively high rainfall of the 1990’s has promoted grass production in the eastern portions of the biome.

In the western portions of the biome, there are alarming trends in woody encroachment with two species in particular (Acacia mellifera and Rhigozum trichotomum) thickening up in regions with a long history of domestic herbivory.

Savanna
The savanna biome comprises the northern and eastern portions South Africa, with the arid savanna extending into the southern Kalahari.  The flora comprises a woody layer (mainly single-stemmed, seasonally deciduous, trees and shrubs), with a ground layer of grasses and forbs. The standing biomass of shrubs and trees can be in excess of 16 tonnes per hectare. The dominant grasses are C₄ and comprise the important production component for domestic livestock. A strong summer seasonality in the rainfall encourages woody shrub production. There is strong evidence of woody shrub encroachment throughout this and other biomes (Hoffman & O'Connor 1999). A number of explanations have been suggested for the increase in woody shrub biomass, including i) a reduction of fire frequency (Trollope, 1980), ii) the removal of grass biomass by domestic herbivory with the resultant success of woody shrubs (du Toit 1967), and iii) the  C₃ shrubs having a competitive advantage over C₄ grasses under elevated CO₂ conditions (Bond & van Wilgen 1996).  Graziers attempt to control the woody encroachment using a number of approaches including clearing-felling; burning followed by intensive browsing by goats; and chemical control. The latter seems to be the favoured approach, with an estimated R10 million spent annually on herbicides. The  biome is occupied by both commercial and communal graziers. In general, the woody encroachment problems are more severe in land under communal tenure, although multiple use ensures that wood is used for fuel, construction and traditional purposes.

Grassland
The grassland biome is situated mainly in the central, high lying regions of South Africa (Figure 5) and occupies some 350 000km2  (O'Connor & Bredenkamp 1997). The biome spans a rainfall gradient from "ca. 400 to >1200mm yr-1, a temperature gradient from frost-free to snow-bound in winter, ranges in altitude from sea level to >3300m, and occurs on a spectrum of soil types from humic clays to poorly structured sands"  (O'Connor & Bredenkamp 1997). Although the general structure is fairly uniform, there is a wide range in floristic composition, associated environmental variables, dynamics and management options. There is a strong dominance of hemicryptophytes of the Poaceae. Standing biomass is moisture dependant, and decreases with the rainfall gradient. Herbivory from domestic and wild herbivores has a decisive impact on standing biomass and species composition.

The biome was originally defined on climatic factors and is limited to summer and strong summer rainfall areas with a summer aridity index between 2.0 and 3.9 (Rutherford & Westfall 1986). Frost is common and occurring for 30-180 days per annum. The most common soil in the biome, accounting for 50% of the area, is the red-yellow-grey latosol plinthic catena. This is followed by black and red clays and solonetzic soils, freely drained latosols, and black clays (Rutherford & Westfall 1986).

Acocks (1953) defined thirteen pure grassland types and six "false" or anthropogenically-induced grasslands, ranging from the so-called "sweet" grasslands of the semi-arid regions of the Eastern Cape to the "sour" grasslands of the high rainfall regions of the Drakensberg. There are now six recognisable grassland floristic regions (O'Connor & Bredenkamp 1997), reflecting a topo-moisture gradient from the dry western region to the eastern  mountains and escarpment (Table 5).

The concepts "sweet" and "sour" refers to the palatability of the grasses, dwarf shrubs and trees to domestic livestock. Although difficult to define in strict scientific sense, these terms have retained their use throughout the farming community,  being applied to both individual species and to components of the landscape. "Sweet veld" usually occurs on eutrophic soils under arid and semi-arid conditions.  These soils are generally derived from the shales, mudstones and sandstones of the Karoo Supergroup. "Sour veld" is associated with the acid soils of quartzite and andesitic origin, and  occurs in higher (>600mm) rainfall and high elevation (>1400m). Ellery et al (1995 ) have suggested that the concept is driven by the C:N ratios of the grasses, and the sweet veld has a lower C:N ratio than sour veld.

In concluding their chapter on the biome, O'Connor & Bredenkamp (1997) report "that the rainfall gradient across the grassland biome is the main determinant of community composition, primary production, foliage nutrient content, nutrient cycling and attributes of species such as photosynthetic pathway, secondary chemicals and phenology. Rainfall in semi-arid regions, and hence production and nutrient cycling, is more variable than in moister regions. Indeed, rainfall regime seems to determine the distribution of the biome both directly (i.e. water balance) and indirectly through fire regime, although biotic effects of grazing can influence biome boundaries. A temperature gradient is also undoubtedly important, and is partly independant of rainfall, although this relationship has not been well investiagted. Soil type is a critical modifier of the influence of rainfall regime at a local or regional scale. Although all grasslands of the biome comprise mainly tufted perennials, it is tentatively suggested that semi-arid grassland has faster turnover of individual tufts, because of the increased frequency of drought related mortality, and therefore has the potential for rapid compositional change. In contrast, tuft turnover and change in high-rainfall regions is slow, because of the stable rainfall regime. It would appear that as a result of these different rainfall patterns, grazing has a more mmediate effect on community change in semi-arid than moist grassland. CHanges in community composition can dramatically influence water balance, production, nutrient cycling, foliage quality, soil loss and fire behaviour. Community change depends on the influence of communities on the abiotic environment and on species attributes, but the response of species to environment is contextual rather than absolute.

Table 2. Regions within the grassland biome (O'Connor & Bredenkamp 1997).

There are currently (2001) about 13.8 million cattle, 25.8 million sheep and 6.3 million goats in South Africa, in addition to smaller numbers of pigs, poultry and farmed ostriches. The total numbers of cattle and small stock fluctuate in response to high and low rainfall years. There are more cattle in the communal than the freehold sector (Table 3), although the communal sector contributes minimally to formal beef sales. Nationally, beef production is the most important livestock related activity, followed by small stock (sheep and goat) production (Table 4). Most of the output from the small stock sector (wool, mohair, mutton and lamb) is exported. The combined livestock sector contributes 75% of total agricultural output (National Department of Agriculture, 1999). Since 1992 there has been a steady increase in the production of chicken meat and a general decline in beef and veal production. The national output of wool has declined from 83Mt in 1992 to 52Mt in 2000.

Table 3.National livestock census 1999.

South Africa also possesses a rich and diverse wildlife resource, and almost 10% of the country is designated as National Parks and formal conservation areas, but a considerable proportion of the wildlife exists outside formally proclaimed conservation areas. Many livestock farmers derive some or all of their income from hunting and/or eco-tourism.