How does energy flow through an ecosystem?

Organisms within an ecosystem are classed as producers, consumers or decomposers. Energy flows through these organisms within the ecosystem.

Producers, such as trees, produce food and begin this cycle. Then, using energy from the sun, they produce food. They do this by photosynthesis. Most producers are plants, but some small organisms produce food through photosynthesis as well.

Producers are eaten by primary consumers that cannot produce food themselves, such as a giraffe. Primary consumers are herbivores which means they only eat plants. Secondary consumers are carnivores such as lions. In a simple food chain, secondary consumers eat primary consumers.

Decomposers and break down dead plants and animals. They also break down the waste of other organisms. Examples of decomposers include bacteria and fungi. Decomposers get their energy from breaking down dead material, e.g. dead producers, dead consumers or fallen leaves. When dead material is decomposed, nutrients are released into the soil. These nutrients are then taken up from the earth by plants. Decomposers are very important for any ecosystem. If they weren’t in the ecosystem, the plants would not get essential nutrients, and dead matter and waste would gather.

A food chain shows the relationships between feeding groups,  illustrating energy flow from producer to tertiary consumer. The image below illustrates this.

A food chain

A food web shows lots of food chains and how they overlap.

A food web

The transfer of nutrients through the ecosystem is known as the nutrient cycle.

The Nutrient Cycle

The nutrient cycle shows pathways through which nutrients flow. All plants and animals depend on nutrients in food for their survival.