all about ecosystems ESchooltoday Home, All Lessons

What is an ecosystemScales of an ecosystemLevels of organisation of an ecosystem
What is a biome
What is a food chainTrophic levels of an ecosystem
The Carbon Cycle
The nitrogen cycle
Important ecosystem terminology


Climate Change
Earth System
Food Waste
Forest Preservation
Genetic Engineering
Natural Resources
Ocean Acidification
ecology space

Trophic levels of food chains

The levels of a food chain (food pyramid) is called Trophic levels. The trophic level of an organism is the level it holds in a food pyramid.
Food chain levels

The sun is the source of all the energy in food chains. Green plants, usually the first level of any food chain, absorb some of the Sun’s light energy to make their own food by photosynthesis. Green plants (autotrophs) are therefore known as ‘Producers’ in a food chain.

ecosystemThe second level of the food chains is called the
Primary Consumer. These consume the green plants. Animals in this group are usually herbivores. Examples include insects, sheep, caterpillars and even cows.

ecosystemThe third in the chain are
Secondary Consumers. These usually eat up the primary consumers and other animal matter. They are commonly called carnivores and examples include lions, snakes and cats.

ecosystemThe fourth level is called
Tertiary Consumers. These are animals that eat secondary consumers.

Quaternary Consumers eat tertiary consumers.

ecosystemAt the top of the levels are
Predators. They are animals that have little or no natural enemies. They are the ‘bosses’ of their ecosystems. Predators feed on preys. A prey is an animal that predators hunt to kill and feed on. Predators include owls, snakes, wild cats, crocodiles and sharks. Humans can also be called predators.

ecosystemWhen any organism dies,
detrivores (like vultures, worms and crabs) eat them up. The rest are broken down by decomposers (mostly bacteria and fungi), and the exchange of energy continues. Decomposers start the cycle again.

previous pageMore on ecosystem

ecology space