Energy Flow in Ecosystems
In this video, I will talk about trophic levels.
All living things require energy in order to stay alive.
There are different models scientist use to show the flow of energy through an ecosystem.
The most common models are food chains and food webs.
Each step in a food chain or food web is a trophic level.
Trophic levels can be represented by numbers, starting at level 1 with plants. Further trophic levels are numbered according to how far the organism is along the food chain.
Level 1: Primary Producers make level one. Examples include Plants and algae that use photosynthesis to make their food
Level 2: Are called primary consumers because they eat other producers.
They are also classified as Herbivores because they only eat plants. A cow is an example
Level 3: Is made up of secondary consumers. They consume level 2 animals.Carnivores who are meat eaters and omnivores are found on level 3
Level 4: This level includes the tertiary consumers. The tertiary consumers eat other carnivores
Level 5: Finally Apex predators are at the top of the food chain. The are carnivores without any predators. This would include lions, great white shark
Let’s take a look at a simple food chain
Level 1 includes your plants and they get energy from the sun
The insects eat the grass so they are primary consumers which are also called herbivores and this is level 2
The bird is found on level 3 and are omnivores and eat the insects and seeds
Level four is a merlin which is a small hawk that feeds on smaller birds. The merlin is a tertiary consumer and is a carnivore that feeds on the song bird.
There is not an apex predator in this food chain
Each time you move from one trophic level to another level only 10 percent of the energy is transferred to the next level This is often referred to as the 10 percent rule.
This explains why as you move up trophic levels there are fewer individuals at each level