Transfer of food energy from source (producer) to organisms consuming it (primary consumers) & further these organisms in turn are eaten up by organisms to which they are food source (secondary consumers) and so on, in a linear series.
Types of Food Chains:
- Grazing Food Chain:
- Starts from living green plants (producers).
- The producers are consumed by herbivores (primary consumers).
- Further, herbivores are eaten up by carnivores (secondary consumers or primary carnivores) and so on.
- Detritus Food Chain:
- Starts from dead/non-living organic matter, which is being broken down by microbes.
- The organic matter is the then consumed by detrivores (primary consumers).
- Detrivores are further eaten up secondary consumers or primary carnivores & so on.
In real life, it is impossible to consider each food chain as an isolated unit. Different food chains are interconnected making a sort of web termed food web.
A food web contains a series of interconnected food chains.
Some other points to consider:
- In all ecosystems, grazing & detritus food chains interconnected.
- Assimilation of whole food consumed does not occur. Some undigested matter /faeces are diverted to detritus food chain.
- Both overgrazing & undergrazing are detrimental as decrease or increase in population of any trophic level will affect the dependent trophical levels.