Consider a food chain of the following: Fish, crab, phytoplankton, shark. Arrange the above chain in the proper order of trophic level.
This trophic level is a depiction of the pond ecosystem.
● The first level is represented by the producers or the autotrophs; for example, phytoplankton and plants. They prepare their own food with the help of energy from sunlight through the process of photosynthesis.
● The second trophic level is characterized by the presence of primary consumers such as crabs inhabiting the pond. Organisms in this level consume the phytoplanktons or producers.
● The third level comprises of the omnivores, especially the fish species, which can feed on both plants.
● The fourth and the top most level is for carnivores or tertiary consumers which are flesh eaters.