Trophic level:The position that an organism occupies in a food chain, or a group of organisms in a community that occupy the same position in food chains.
It is possible to classify the way organisms obtain energy into two categories.
Producers or Autotrophs: These manufacture their own food from simple inorganic substances (plants). Consumers or Heterotrophs: Feed on autotrophs or other heterotrophs to obtain energy (herbivores, carnivores, omnivores, detrivores and decomposers
But within the consumers their is a feeding hierarchy of feeding
Plants capture the suns energy and convert it to glucose, herbivores eat plants and carnivores eat herbivores – different feeding levels (Greek for food is trophe)Trophic level 1 – producerTrophic level 2 – herbivore (primary consumers)Trophic level 3 – carnivore (secondary consumers)Trophic level 4 – carnivore (tertiary consumer)
The first trophic level, the autotrophs supports the energy requirements of all the other trophic levels above.