What Is a Food Chain?
In an ecosystem there are different types of living species, including the plants animals, birds, insects, reptiles and other species, which all are depended on each other for food and energy. The movement of nutrients and energy between the different living organisms at various trophic levels forms a food chain.
Overall, a food chain explains the chain of series or a continuity of events that occurs within an ecosystem, where a living species eat other organisms, which later becomes prey for some other larger organism.
The food chain also explains about the various feeding pattern or type of relationship involved between each living organisms. Every level in a food chain is known as a trophic level, the continuous stages in a food chain, starting with producers at the bottom, followed by primary consumers, secondary consumers and tertiary consumers.
Also Refer: Food Web
The food chain is classified into two different types based on the produced energy:
- Grazing food chain
- Detritus food chain
What is the Grazing Food Chain?
The type of food chain in which the energy in the gained from photosynthesis is termed as a grazing food chain. In this food chain the starting point are the producers- plants and the first energy transfer is from plants to herbivores. Here, received energy is at the lowest trophic level. In an aquatic ecosystem, the grazing food chain plays a major role in the transfer of energy flow. Based on the sequence of organisms, grazing food chain is further classified into two different types :
- Predator chain -the sequence of organisms generally increases in size.
- Parasitic chain-the sequence of organisms generally decreases in size.
Examples of Grazing Food Chain
The grazing food chain is a type of food chain, in which the flow of energy is transferred between the autotrophic plants and plant eating animals -herbivores.
- Phytoplankton → Zooplankton → Fishes → Larger fishes
The phytoplankton is attacked by zooplankton and finally, the zooplankton is attacked by fishes and followed by the larger predators.
- Grasses → Rabbits → Wolves→ Larger predators
The grasses are attacked by rabbits and finally, the rabbits are attacked by wolves and followed by the other predators.
Herbs/ small plants/ grass → Deer → Lion →Larger predators
The small plants or grass is eaten by a deer and the deer is later eaten by a lion and followed by the other predators.
Read more: Grazing food chain
What Is the Detritus Food Chain?
The detritus food chain begins with dead organic materials is called a detritus food chain. Dead organic matter and the organisms feeding on the dead and decaying matter are referred to as detritivores or decomposers. These detritivores are eaten by predators. The detritus food chain produces a large amount of energy to the ecosystem. Detritus food chains are found in a variety of places such as the bottom of the ocean, sea, ponds and also in lakes.
Examples of Detritus
- Leaves → Insect larvae → Fishes → Larger predators
Here, the food chain that starts with the leaves of a mangrove tree. When the leaves of a red mangrove tree fall into a shallow water body, only about five per cent of the leaves are eaten by phytophagous – a plant eating insects before they fall. The parts of the leaves are eaten by smaller organisms like insect larvae, crabs, copepods, etc. Later these organisms are consumed by fishes who are carnivores. Finally, these fishes are eaten by larger fishes or fish-eating birds.
- Dead organic wastes → Micro organisms → Detritivore organisms
The type of food chain that starts with the dead organic wastes.
Here, the food chain that starts with the dead organic wastes. When these wastes are consumed by microorganisms like bacteria or fungi. Later, these microscopic organisms are consumed by other detritivore organisms like snails, earthworms and so on.
Read more: Detritus food chains
|Grazing food chain||Detritus food chain|
|In this food chain, producers serves as the primary source of energy and constitute the first trophic level.||In this food chain, dead and decaying matter serves as the primary source of energy. Detritivores or decomposers feed on this matter and releases the nutrients back into the atmosphere.|
|Source of Energy|
|Energy for the grazing food chain is obtained directly from the sunlight.||Energy for the detritus food chain is obtained from the organic debris|
|A grazing food chain is usually larger compared to the detritus food chain.||Detritus food chain is usually smaller compared to the grazing food chain.|
|Grazing food chain releases energy into the ecosystem.||Detritus food chain utilizes energy from the ecosystem.|
|Role in the Food chain|
|Grazing food chain helps in adding energy.||Detritus food chain helps in fixing inorganic nutrients.|
|Grazing food chain involves all macroscopic organisms.||Detritus food chain involves subsoil organisms, which can be macroscopic or microscopic.|
Also Refer: Differences between Autotrophs and Heterotrophs
There are many more differences between grazing and detritus food chains. Stay tuned with BYJU’S Biology for more differences and other Biology related topics.