Tsende Sandveld Letaba and Shingwedzi Regions. Landscape 11 Kruger National Park

Location and Geomorphology

This landscape forms the high lying area between the Letaba and Shingwedzi Rivers on the western side of the KNP. North of the Shingwedzi the landscape is discontinuous with sub-sections right up to the Mphongolo River. This landscape is undulating granite terrain with distinct uplands and bottomlands. Amphibolite from the Swaziland System occurs fairly regularly and the remainder of the landscape is intersected by numerous dolerite instrusions. An interesting phenomenon about the dolerite intrusions is that they have a south-west/north-east orientation. This is explained by the theory that, as a result of the eastward movement of a portion of the African continent, a downward pressure is being exerted on the eastern edge of the continent which has resulted in a south-west/north-east tension. A result of this tension was that cracks formed into which the melted magma has entered to cause the south-west/north-east orientated dolerite intrusions (Brandt 1948; Schutte 1974).

The topography of the landscape is similar to that of the Phalaborwa Sandveld (Landscape 8). It is drained by the Shingwedzi with all its tributaries, the Tsende, the Byashishi and to a lesser degree the Phugwane and Mphongolo. The altitude varies between 300 and 450 metres and an important characteristic of the landscape is the adsence of prominent koppies. On the other hand, Veldpans are a very common phenomenon and can be seen as a unique characteristic. The following large pans occur in this landscape: Mahubyeni, Mhlatuba, Tol-se-Pan, Basa-Basa, Olifantbadpan and Uitspan. This landscape occupies 1156 km/2 or 5.9 percent of the KNP.

Climate

According to Gertenbach (1980) this area receives between 450 and 550 mm rain per year. Shangoni in the north-western corner of this landscape has an annual average rainfall of 572 mm and it can be concluded that this landscape, as a result of orographical conditions, receives more rain than the adjacent Letaba River Rugged Veld (Landscape 10). Due to the high altitude of this area frost is the exception. Average monthly maximum and minimum temperatures for Shingwedzi are given in Table 6.

Table 6 … Temperature data for Shingwedzi. (Data collected since September 1981)

Soil Pattern

The soil pattern of the landscape is comparable to that of landscapes 5, 6 and 8. The soils of the uplands are sandy with less than 15 percent clay in the A-horizon. The dominant soil Forms are Hutton, Clovelly and Glenrosa. The seepline is poorly developed to absent and the soils of the bottomlands are more clayey, with the dominant Forms being Valsrivier, Sterkspruit, Glenrosa with Estcourt as an exception. The soils originating from amphibolite of the Swaziland System are deeper and red in colour. Dominant soil Forms are Hutton and Glenrosa with the more clayey series most common. Soils that develop on dolerite can be red or even black in colour. Expected soil Forms are Swartland, Glenrosa, Hutton, Mayo and Milkwood.
Fig. 25. Landscape 11. Upland Tsende Sandveld – page 47
Fig. 26. Landscape 11. Bottomland Tsende Sandveld. – page 47

Vegetation

The vegetation on the uplands of this landscape is moderately high shrub savanna with single large trees (Fig. 25). The structural analysis of the vegetation of an upland, middleslope and a bottomland is more or less as follows:

Percentage Crown Cover

The dominant woody plants of this landscape are: Colophospermum mopane and Combretum apiculatum. On the sandy uplands the latter is more dominant. However, moving towards the bottomlands the soil becomes more clayey and Combretum apiculatum gives way to Colophospermum mopane (Fig. 26) Plants more common to the uplands are Combretum apiculatum, Colophospermum mopane, Cissus cornifolia, Albizia Harveyi, Tephrosia sericea, Terminalia sericea, Grewia bicolor, Dichrostachys cinerea subsp. Africana, Sclerocarya caffra, Dalbergia melanoxylon, Peltophorum africanum, Strychnos madagascariensis and Commiphora africana. The field layer is dense, approximately 750 mm high and is dominated by Digitaria eriantha var. pentzii, Panicum maximum, Heteropogon contortus, Pogonarthria squarrosa, Schmidtia pappophoroides, Tephrosia polystachya, Cassia absus and Cyperus rupestris. Other species in the field layer are: Brachiaria nigropedata, Aristida meridionalis, Perotis patens, Eragrostis rigidior, Tricholaena monachne,Rhynchelytrum repens, Bothriochloa radicans, Aristida congesta subsp. Barbicollis, Andropogon gayanus, Vigna stenolobum, Dolichos trilobus, Agathisanthemum bojeri, Cassia mimosoides, Clerodendrum ternatum, Phyllanthus asperulatus, Rhynchosia totta, Talinum caffrum, Ipomoea magnusiana, Indigofera filipes, Merremia tridentate, Hemizygia bracteosa, Tephrosia longipes, Jatropha zeyheri, Evolvulus alsinoides and Fimbristylis complanata.

Woody plants in the bottomlands are Colophospermum mopane, Combretum apiculatum, Lonchocarpus capassa, Grewia monticola, Acacia nigrescens, Combretum hereroense, Acacia tortilis, Bridelia mollis, Grewia bicolor, Cassia abbreviate, Grewia flavescens and Albizia harveyi. The field layer of the bottomlands are most dense and species such as Eragrostis superba, Bothriochloa radicans, Themeda triandra, Urochloa mosambicensis, Panicum coloratum, Cymbopogon plurinodis and Enneapogon cenchroides are more common. Associated forbs are Corchorus asplenifolius, Cerathotheca triloba, Heliotropium steudneri, Melhania forbesii, Orthosiphon australis, Crotolaria virgulata, Cleome monophylla, Blepharis integrifolia, Hermbstaedtia odorata and Asparagus plumosus. Along certain spruits on brackish spots a type of vegetation occurs that differs from the normal bottomlands (Fig. 27). Woody species under such conditions are Euclea divinorum, Colophospermum mopane, Spirostachys africana, Ehretia rigida and

Fig. 27. Landscape 11. Sodic bottomland Tsende Sandveld. – page 49
Fig. 28. Landscape 11. Dolerite intrusion Tsende Sandveld – page 49
Albizia harveyi with Sporobolus fimbriatus, Dactyloctenium aegyptium, Eragrostis lehmanniana, Sporobolus nitens, Chloris virgata, Portulaca kermesina, Pharnaceum elongatum, Justicia flava, Mariscus rehmannianus, Asparagus buchananii and Sansevieria grandis as the dominants in the field layer.

On the clayey soil originating from dolerite and amphibolite, the mopanies are usually more dense and larger trees occur (Fig.28). The shrub layer is not strongly developed and the field layer is dominated by dense stands of Themeda triandra and Bothriochloa radicans. The denser grass cover possibly results in hotter fires which control the shrub layer.

The riverine vegetation of this landscape is the same as that of the Combretum spp./Colophospermum mopane Bushveld of the Timbavati area (Landscape 6).

Fauna

The Tsende Sandveld is also preferred habitat for sable antelope. Elephant, buffalo, kudu and zebra are present while waterbuck and impala are restricted to areas close to water. Eland are fairly common in this area and in 1981 a herd of +/- 50 animals were counted along the upper course of the Tsende spruit. White rhino had become extinct in this part of the KNP, but in 1964, 13 bulls and three cows were released along the Shongololo spruit. At first they wandered all over the area, eventually settling down and at present a population of 30 animals including calves are regularly seen. Although giraffe are relatively scarce in the mopane-veld, a group of 20 to 30 are regularly encountered along the Shongololo spruit. A few groups of roan antelope also occur in this landscape but these animals are more associated with Landscape 24 which is basically a gabbro intrusion which cuts through the Tsende Sandveld. Lion, leopard and hyaena are scarce and plains loving animals such as wildebeest and tsessebe (Damaliscus lunatus) are altogether absent.