noun, plural: trophic levels
A trophic level refers to a level or a position in a food chain or ecological pyramid. It is occupied by a group of organisms that have a similar feeding mode. At the base of an ecological pyramid is trophic level 1. A food chain would start as well at trophic level 1. The trophic level 1 is occupied by the primary producers (e.g. plants). The primary producers include a group of organisms producing their own food. As the given example, the plants are primary producers for their ability to manufacture their food through photosynthesis. The next trophic level in a food chain or ecological pyramid is the trophic level 2. In this level, the organisms occupying this level feed on the primary producers and are referred to as primary consumers, i.e. herbivores. Organisms feeding on the herbivores, called predators, occupy the next trophic level, i.e. trophic level 3. The trophic levels 4 or 5 are occupied by carnivores or apex predators. The last of the trophic level is occupied by decomposers, i.e.detrivores.
Word origin: Greek trophē (food)