Grazing Food Chain - Food Chain

Grazing food chains are quite familiar to most of us. Cow or deer grazing in a field represent a grazing food chain. Similarly, eating of phytoplanktonic algae by zooplankton and fish is another example of grazing food chain. In most ecosystems, only a small proportion of the total community energy flows through grazing food chains. Also at each step, significant amount of organic matter is shunted to detritus food chain-through death, decay and excretion by living organisms.

The grazing food chains in forest and ocean represent two extreme types. Ocean food chains are among the longest, up to five links, in contrast to forest types which mostly consist of three or rarely four links. One of the reasons for the longer length of grazing food chains in aquatic ecosystems is the small size of the phytoplankton and zooplankton that chiefly comprise the first two trophic levels. If there are many small herbivores at level two, this means that the carnivores at level three also can be relatively small and numerous, and an additional carnivore level can be accommodated before the last level, represented by a relatively small number of large carnivores.