Grasslands of the World.pdf - Disasters and Conflicts - UNEP

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Grasslands of the world
Figure 3.5
The coefficient of variation in annual rainfall for South Africa . Derived from the
long-term rainfall records (50 years or more data) from 1015 stations.
exceptional circumstances to assist land users. Since 1994, this intervention has
been discouraged; instead, graziers are encouraged to plan their production
system within the long-term expectations of their farms .
Seasonality of rainfall
There are three major zones within the country, namely the winter rainfall
region of the western, southwestern and southern Cape; the bimodal rainfall
region of the Eastern Cape; and the strong summer seasonality of the central
high-veldt 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 southwestern 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 on 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
Temperatures in South Africa are strongly determined by elevation and distance
from the sea. The high elevation (1 500–1 700 m) inland regions experience a
warm summer (January) with mean daily maximum temperatures of 26–28°C