Question

Name the type of food chains responsible for the flow of larger fraction of energy in aquatic and a terrestrial ecosystem respectively. Mention one difference b/w the 2 food chains.

Answer 1

Grazing food chain (GFC) is the major form of energy flow in an aquatic ecosystem. In terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain (DFC) than through the GFC.
Differences between the two food chain are as follows:

Grazing food chain	Detritus food chain
The primary source of energy is Sun.	The primary source of energy is detritus
The grazing food chain includes the producers i.e green plants at first trophic level	The first trophic level includes the detritivores (including protozoans, bacteria, fungi, etc which feed upon the detritus)
Producers are further consumed by primary consumers i.e herbivores. These herbivores form the next trophic level. Herbivore s are consumed by carnivores then these in turn are consumed by larger carnivores	Detrivores( mixed of herbivores, carnivores, omnivores, that means does not belong to specific category ) are further consumed by small detrivores consumers such as insect larvae,molluscs , etc. Then these in turn are consumed by another animals called small carnivores such a small fish, minnows, etc . The small carnivores are consumed by large carnivores such as large fishes.
Major form of energy flow in aquatic ecosystem	Major form of energy flow in terrestrial ecosystem
It contributes, comparatively lesser to energy flow than detritus food chain	Detritus food chain contributes to larger amount of energy flow than other food chains, as the organisms present in every food chain (plant or animal) will die and decomposition occurs. Moreover, the organisms release some of their energies through excreta or waste matters which are absorbed by this detrivores.
This type of food chain contain larger sized organisms in comparison to detritus food chain	This type of food chain contain smaller sized organisms in comparison to grazing food chain
Generally longer in length	Generally shorter in length