Energy in Ecosystems

Energy transfer in ecosystems

Re-cap

Write down 2 food chains from this diagram

What does it show?

What is this diagram?

Energy in Ecosystems

Today we are learning about:

• How energy is transferred in ecosystems.• Where energy is lost in a food chain.• What energy is available to the next level in a food chain.Success criteria• Explain where energy goes in food chains• How much is lost and how much is passed on between levels.

Energy in Ecosystems

This is a typical food chain.

Grass grasshopper frog snake

What do you think happens to the energy not passed on?

How much energy do you think is passedon from one organism to the next?

What do the arrows represent?

Where do you think the original energy came fromfor this food chain?

Energy in Ecosystems

Energy not available to the next organism is about 90%

Energy is lost in these ways

Movement Heat production

Undigested waste

Energy in Ecosystems

How much energy is available to the next level?

Yes only 10% which can be used for growth.

In a typical food chain the energy available to the next level in the chain quickly decreases for example.

If the units of energy started at 100,000 for the grass by the snake it would be 100.100,000 10,000 1000 100

Energy in Ecosystems

This dramatic loss of energy limits the lengthof food chains as there needs to be enoughenergy to support the next organism in the foodchain.What have we learned?Are food chains efficient at passing energy on?

How much is lost?

How much is available to be passed on to the next level in the chain?

What happens to most of the energy in the food chain?