1. Ecosystems In this presentation you will:
explore the living and non-living features of ecosystems
Next >

2. Introduction
A group of organisms interacting with each other, and with the environment in which they live, is called an ecosystem.
An ecosystem can exist in a very small place, like a puddle, or a very large place like a forest.
Next >

3. Introduction
Each ecosystem has a characteristic group of plants and animals that live in a community.
These are the biotic (living) factors of the ecosystem.
Next >

4. Introduction
These living organisms influence, and are influenced by, the abiotic (non-living) factors of the environment.
For example, climate, water and soil composition (what the soil consists of).
Next >

5. Question 1 What is an ecosystem?
A) non-living organisms interacting with each other only
B) living organisms interacting with each other only
C) living organisms interacting with each other and their environment
D) living organisms that do not interact
Next >

6. Question 1 What is an ecosystem?
A) non-living organisms interacting with each other only
B) living organisms interacting with each other only
C) living organisms interacting with each other and their environment
D) living organisms that do not interact
Next >

7. Habitats A place where organisms live is called a habitat.
Habitats can range from large oceans, deserts, forests, lakes and rivers…
…to small garden ponds, garden hedges and aquariums.
For an ecosystem to function properly, there needs to be a balance between organisms and their environment.
Next >

8. Stress Within Habitats
Factors that upset this balance are called stress factors.
Stress within an ecosystem can come from both biotic and abiotic factors.
Any form of stress on the homes of organisms will put pressure on their ability to survive there.
Next >

9. Biotic Factors
The biotic factors of an ecosystem include everything living in it.
They range from microscopic bacteria, algae and fungi, to plants, trees, insects and animals of all shapes and sizes.
Next >

10. Biotic Factors
Biotic factors that can affect an organism in its environment include:
how many organisms, of the same or different species, compete (battle) for food, space and shelter.
the presence and numbers of predators the organism has (animals that can kill and eat it).
Next >

11. Biotic Factors
the presence and numbers of organisms that are able to help the particular organism to survive (symbiosis).
For example, insects help flowers by carrying away pollen needed for reproduction.
Next >

12. Biotic and Abiotic Features
The non-living features of a habitat are known as abiotic features.
These are split into two categories:
edaphic features – the soil or water and all their physical and chemical characteristics
Next >

13. Biotic and Abiotic Features
climatic features – light, water temperature, moisture and the stability, salinity (concentration of salt), and variability of these features
Next >

14. Question 2 Which of the following is a biotic factor of a habitat?
A) Light levels
B) The amount of rainfall
C) Soil
D) Plants
Next >

15. Question 2 Which of the following is a biotic factor of a habitat?
A) Light levels
B) The amount of rainfall
C) Soil
D) Plants
Next >

16. Measuring Biotic Material
We can study the biotic factors within a chosen habitat by counting the populations of species found there.
If the chosen habitat is a grassy field, we can use a square frame, called a quadrat.
Next >

17. Measuring Biotic Material
The quadrat would be placed randomly on a patch of grass.
Insect trap
Both plants and animals inside the quadrat can be counted.
Pooter
Insects can be collected using a pooter or insect trap if they are on the ground.
Kite net
A kite net can be used if they are in the air.
Next >

18. Measuring Abiotic Material
We can study the abiotic factors by using the following measuring instruments:
Anemometers measure wind speed.
Thermometers measure air, soil or water temperature.
Next >

19. Measuring Abiotic Material
Rain gauges measure rainfall.
Light meters measure light level.
pH test kits measure acidity level.
Water quality kits measure things like oxygen and nutrients.
Next >

20. Interactions in an Ecosystem
The interactions between the biotic and abiotic factors can be seen in an aquarium.
Biotic factors
The biotic factors of this aquarium are all the living organisms.
These include fish, plants and microorganisms.
Next >

21. Interactions in an Ecosystem
The abiotic factors of the aquarium are all the non-living things.
These include light, water temperature, and nutrients and oxygen in the water.
Abiotic factors
Next >

22. Interactions in an Ecosystem
The biotic factors rely on each other and on the abiotic factors.
For example, fish take their oxygen from the water, so they rely on the water being sufficiently oxygenated.
Oxygen-rich water
Cool water can hold more oxygen than warm water, so temperature is important to the fish.
Next >

23. Interactions in an Ecosystem
Providing there is sufficient light, plants will photosynthesize, giving off oxygen into the water.
Oxygen
This will increase the oxygen available to the fish.
Light
Next >

24. Interactions in an Ecosystem
Fish rely on rocks and other non-living structures for shelter.
However, they will also use plants for shelter too.
Next >

25. Interactions in an Ecosystem
Fish waste adds nutrients to the water, helping plants and algae to thrive.
Fish waste
Nutrients
This is of great benefit to many types of fish and water snails as they love to eat algae.
Algae
Snails / Fish
Next >

26. Question 3
Which of the following instruments is NOT a way of measuring abiotic material in a habitat?
A) Light meters
B) Water test kit
C) Anemometers
D) Pooter
Next >

27. Question 3
Which of the following instruments is NOT a way of measuring abiotic material in a habitat?
A) Light meters
B) Water test kit
C) Anemometers
D) Pooter
Next >

28. Summary In this presentation you have seen:
the biotic and abiotic features of ecosystems
End >