Mopane Shrubveld on Calcrete north of the KNP Nwambia Sandveld
Location and Geomorphology
This mopane-shrubveld occurs as two isolated areas in the far north of the KNP. One area is situated on the eastern boundary of the KNP North of the Nwambia Sandveld and the other along the western boundary on the watershed between the Limpopo and the Levubu Rivers. The underlying geological material of this landscape consists of the Malvernia Formations (Schutte 1974) which decompose to give rise to soil with a lot of lime concretions.
The area is situated between 215 and 445 metres above sea level. The eastern and western sub-regions are drained by the Shilahlandonga and Mutale spruits respectively. The terrain is intersected to undulating and covers 117 km/2 or 0.6 percent of the area of the KNP. The Malonga spring is located on the brink of this landscape.
Rainfall in this vicinity varies between 450 and 500 mm per year and the temperature is high in the summer and mild during the winter. The role that fog plays in winter in the dry mountainous areas will be explained in the discussion of Landscape 31. Temperature data for Shingwedzi (Table 6) is the most applicable to this landscape.
The soils of this landscape are shallow and calcareous. According to Van Rooyen (1978) as much as 10 percent of the surface of the soil is covered by stones and the pH varies between 7,9 and 8,4. Most important soil Forms are Milkwood, Mispah, Glenrosa and Mayo while the occurrence of lithosols are common.
Structurally the two sub-units of this landscape differ from one another. The sub-unit next to the eastern boundary at Shilahlandonga is mainly a shrub savanna (Fig. 60), while the sub-unit on the western boundary can be regarded as a tree savanna.
Fig. 60. Landscape 26. Colophospermum mopane Shrubveld on Calcrete. – page 93
The dominant woody species are: Colophospermum mopane, Maytenus heterophylla, Euclea schimperi, Grewia bicolor, Acacia nigrescens, Combretum apiculatum, Terminalia prunioides, Euclea divinorum, Sterculia rogersii,Commiphora mollis, Zanthoxylum humilis and Dalbergia melanoxylon. The field layer is characterized by the presence of species such as Enneapogon scoparius, Seddera capensis and Aristida congesta subsp. congesta and Panicum maximum does not occur in this area. Other herbaceous species are Heteropogon contortus, Fingerhutia africana, Eragrostis superba, Digitaria eriantha, Rhynchelytrum villosum, Indigofera vicioides, Rhynchosia totta, Barleria lancifolia, Tephrosia polystachya, Phyllanthus pentandrus, Hibiscus micranthus and Acalypha indica. Androstachys johnsonii-bush occurs on certain slopes of this landscape. The floristic composition of this bush will, however, be described in more detail inder Landscape 31. This landscape as a whole is unique, not only in the KNP but also in Sout Africa. This fact necessitates special conservation status for the area.
This Colophospermum mopane Shrubveld on Calcrete is not a landscape that supports a high density of game, Zebra, kudu, steenbok, Sharpe’s grysbok, Nyala, eland and elephant are the most important animals, but they always occur in small numbers.