4.1 Different ecosystems

Natural sciences

Grade 8

Environment and interactions

Module 30

Different ecosystems

Our country has a wealth of widely differing kinds of ecosystems.

If possible, your teacher will take you to one or more of these ecosystems.

Activity:

To discuss the role of a grassland ecosystem

[lo 1.3]

In large parts of our country grass forms the greatest part of the ecosystems. We can also use the term BIOME to refer to the parts of the country that show more or less the same ecological characteristics. For instance, there is a grassland biome. A grassland biome can be described as a large ecosystem or it can be divided into smaller grassland ecosystems.

Knowledge of the grassland biome and grassland ecosystems is important in South Africa, because great parts of the country are utilized for grazing animals.

Game such as impala, buffalo and springbuck are also grazing livestock.

The type of grass in an ecosystem is mainly determined by the nature of the soil.

Grassland biomes are named according to the dominant grass type that is found in the system.

The main types of grassland ecosystems (actually biomes) are:

1. sweet veld – low rainfall areas; good livestock grazing;

2. sour veld – high rainfall areas; not very good grazing;

3. mixed veld.

Red grass ( Themeda triandra ) is a well-known grass type that is very nutritious for livestock.

Over-grazing is the most serious offence that a farmer can commit, because it leads to soil-erosion, desert creation and eventual famine.

Have a class debate on the following question:

• Is the practice of regularly burning grass good or bad for the environment?

• Write down the advantages and disadvantages of burning grassland, as mentioned in the debate, in the columns below:

Assessment of DEBATE:

Have you made a meaningful contribution to the debate? [ LO 1.3]

Activity:

To discuss forest/tree ecosystems

[lo 1.2; lo1.3; lo 2.4]

Trees are not only producers , but as a result of their size they also create a habitat for certain species.

Animal and plant species inhabit trees.

The leaf cover of trees provides shelter for animals, while the bark and fissures in the trees also provide a habitat for numerous insect species. The leaf cover also creates a shady environment in which shade-loving, low-growing plants can flourish.