What happens to most of the energy in ecosystems?

The first source of energy in an ecosystem is the sun. As the sun's energy flows through the ecosystem, some of it is lost to the environment as heat. Energy that is lost as heat cannot be recycled. Thus, in an ecosystem, energy flow is non-cyclic or linear.

Let's see how the sun's energy flows through the ecosystem.

1. First source of energy is the sun


2. Chlorophyll in producers absorb light energy and converts the light energy into chemical energy during photosynthesis.


3. Energy in the producers is passed from one trophic level to another by feeding.


4. As the flow of energy through the ecosystem is non-cyclic, energy is released as heat to the environment. This heat energy is not returned to to the same system or organisms that produced in it. Hence, it cannot be recycled in the ecosystem.


5. Dead organisms and egested and excreted materials contain trapped chemical energy and use some of it for their needs. The rest of the energy is lost as heat.

http://www.dlese.org/cmb/images/Flow%20of%20Energy%20in%20Ecosystems.jpg