The ecosystem

Natural sciences

Grade 8

Environment

Module 29

The ecosystem

ECOLOGY is the study of organisms in their natural environment and the interaction between them.

Activity:

To be able to interpret representations of different ecological environments

[lo 2.2; lo 2.3]

QUESTIONS

1. What is an ECOLOGICAL ENVIRONMENT?

2. What, are the basic components or parts of all ecological environments?

3. Bios is the Greek word for Life .

What, do you think, the following concepts mean? (Ask your teacher to explain.)

3.1 abiotic

3.2 biotic

3.3 factor

4. An ecological environment can be described as an ECOSYSTEM.

4.1 An ecosystem is

An ECOSYSTEM is, the living and non-living components of a certain environment and the interaction between the components.

The study of ecosystems and the interactions between the organisms and their environment is called ECOLOGY .

.

To examine part of a garden as an ecological environment (ecosystem)

[lo 1.1; lo 1.2; lo 2.1; lo 2.2]

Your teacher will arrange a visit to a suitable garden in your neighbourhood, or perhaps just to a part of your school grounds. It must be an area where the gardener does not work every day.

• Why is that so?

1. Divide into groups and sit down in the garden. There must be quite a bit of space around each group. Sit absolutely still for at least five minutes.

2. Be aware of everything that can be observed.

3. Each group picks a single leaf (with permission) of each kind of plant that is visible in the area. Place it between two clean sheets of paper in a thick book. Give each plant your own name.

4. Count the number of plant and animal groups in your delimited area and tabulate the information below.

5. Make a list of all the non-living (abiotic) factors that determine the nature of the environment.

6. Abiotic factors:

Assessment of the GARDEN RESEARCH:

Were you able to carry out the assignment and write down results?

[LO 1.1; LO 1.2]

• So far you have determined the following:

That a population is a group of similar organisms in a certain environment . The numbers in your column graph indicate the population size . The population size can be determined by using various methods and formulas.

The home of a plant or animal is called its habitat .

The role that is played by an organism in its environment refers to the “work” that it does, and is called its niche .

A community is made up of all the populations that occur in one area.

A herbarium is made by collecting and storing leaf material as you have done. Ask your teacher to tell you more about this. You could also research this topic on your own. Why don’t you ask your teacher to allocate some space in the classroom so that you can all exhibit your examples?

Let us see what you have learnt:

• Do the following exercise. Write down a letter from Column B next to the number that is related to it from Column A. Write these letters in the squares.

Assessment of column exercise

Could you answer the questions successfully?

[LO 2.1]

Assessment

LO 1: Scientific investigations:

The learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts.

This is evident when the learner:

• plans investigations;
• conducts investigations and collects data.

LO 2: Constructing Science Knowledge:

The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

This is evident when the learner:

• recalls meaningful information;
• categorises information;

2.3 interprets information.

Memorandum

Activity : Interpreting representations of different ecological environments

Questions

1.. A defined area with all the living and non-living factors in it (biotic and a biotic components).

2. Light, air, water, soil, animals, plants.

3..

3.1 a biotic: all non-living parts, e.g. air, water.

3.2 biotic: all living organisms, e.g. plants, animals.

3.3 factor: an element of cause that contributes to a result; the nature of something, e.g. an environment that has a determining effect.

4.a. An ecosystem is a particular area with all the living and non-living factors that determine the nature of the area, as well as the living organisms that occur in the area and interact with one another and with the non-living factors of the

Activity: Examining a section of the garden as an ecological environment (ecosystem)

The visit to the garden. Why must an uncultivated part of the garden be examined? The gardener should be persuaded to steer clear and not interfere.

Tables: learners compile their own lists:

Importance of location, date and time: A biotic factors vary continually and the behaviour and presence of organisms therefore also vary.

Column graph: Utilisation of both the X-axis and the Y-axis is important. The factor that affects the data or lends significance to it is entered on the x-axis. The effect of this factor is entered on the Y-axis. Ensure that the learners name the X- and Y-axes correctly and that they have a thorough grasp of the importance of it: X-axis: plant species; Y-axis: numbers representing each plant species.

Complete the following column-related question:

1. C
2. D
3. B
4. A
5. E
6. G
7. F