Energy Flow Through the Ecosystem
case study: Swiss Alpine Food Web
What we need to know/do
- What is energy used for and where does it come from?
- How is energy moved (and lost) through an ecosystem?
- Construct a fully labelled food web
- Calculate energy loss (as a percentage) from the food web
- Explain how decrease in populations can cause changes in an ecosystem
The Sun!
How big is the Sun?
Energy for almost all of the plants and animals (including you!) originates from our Sun.
Plants use this energy to make food (sugars) in a chemical reaction called photosynthesis.
These plants are then eaten by animals and so the energy is passed on
These animals are eaten by other animals....and the energy is passed on again!
Star Size Comparison HD
What is energy used for?
Look at the pictures below, identify the uses of energy in each picture...
Energy is measured in Joules (J)
Food Webs
Food webs are diagrams that show how energy from the sun is used by plants and animals.
Key words
Producer - plants that use energy from the sun to make food (sugar)
Herbivore - animals that eat plants
Carnivore - animals that eat animals
Omnivore - animals that eat plants AND animals