North America – the Prairies
Asia and Europe – the Steppes
South America – the Pampas
Australia – the Downlands
South Africa – the Veld
- In the RSA, the Transvaal Highveld is typical of the grassland biome.
- The trees are sensitive to frost and are therefore mainly restricted to riverbeds. Exotic trees like eucalyptus and pine trees, which were introduced by people, do well in the region. The main type of vegetation of this biome in South Africa is the local perennial red grass.
- Large parts of the biome have been altered through the intervention of people. Areas have been ploughed to grow mealies and wheat, or are used for grazing. Overgrazing results in the deterioration of the soil and erosion follows. The original animal life has also largely vanished. In South Africa, these parts have been destroyed by mining and the resultant urban development.
DESERT BIOME
- Semi-deserts and deserts, in particular, are those areas of the world where there is an extreme shortage of water because of very low rainfall. The average annual precipitation usually is below 250 mm and there may be years in which no rain is recorded. Daytime temperatures in summer are very high, although they may be more bearable than the high temperatures of the Tropical rainforests because of the low moisture content of the atmosphere. The nights are cold because of very fast cooling when the sun sets.
- Typical climatic features of semi-desert and desert environments are:
- Low annual rainfall (less than 250 mm per year)
- Unreliable precipitation (varies from year to year)
- Low moisture content of the atmosphere
- High evaporation
- Extreme daily fluctuation in temperature
-
The true deserts are on the five continents:
Namib Southern Africa / Namibia
Sahara North Africa
Thar Pakistan / India
Ar Rub’ al Khali Saudi Arabia
Taklimakan China
Alacama South America (Chile / Peru)
Mojave North America
- Vegetation here is either very sparse or non-existent.
- Most of the plants that are found here are
annual plants that complete their life cycle – germination, growth, flowering, seeding and wilting – in a few months. In this regard, you might picture Namaqualand after rain!
- The vegetation in
semi-desert regions is suitable for grazing. The plants are xerophytes – plants that are well adapted to the dry conditions. Some have leaves that are covered with fine hairs or with a waxy layer to restrict evaporation. Others like vygies (mesems) are able to store water in the plant tissue. They are called
succulents .
- Semi-deserts occur over large areas of the world. They form the border areas of true deserts, and together with deserts they cover approximately one-third of the earth’s surface. In South Africa the
Karoo and the
Kalahari are examples of semi-deserts.
Activity 4:
To do research on desert expansion and write a report about it
[lo 1.4, 2.3]
People are responsible for the desert regions becoming bigger and bigger. Do research on this topic and write a report of approximately one page. Make suggestions on how the problem can be addressed.
