trophic level

American  

noun

Ecology.

1. any class of organisms that occupy the same position in a food chain, as primary consumers, secondary consumers, and tertiary consumers.

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trophic level Scientific  

1. Any of the sequential stages in a food chain, occupied by producers at the bottom and in turn by primary, secondary, and tertiary consumers. Decomposers (detritivores) are sometimes considered to occupy their own trophic level.

2. ◆ The rate at which energy is transferred from one trophic level to the next is called the ecological efficiency. Consumers at each level convert an average of only about 10 percent of the chemical energy in their food to their own organic tissue. Since plants can only convert approximately 1 percent of incident sunlight into chemical energy at the lowest trophic level (the bottom of the food chain), the percentage of the energy in incident sunlight that reaches a tertiary consumer is about 0.0001.

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Etymology

Origin of trophic level

First recorded in 1940–45; see trophic ( def. )

Example Sentences

The discovery of predators operating at a seventh trophic level highlights just how rich and complex the Paja ecosystem once was.

From Science Daily • Dec. 19, 2025

Energy is lost as heat between each trophic level due to the second law of thermodynamics.

From Textbooks • Jun. 9, 2022

Each organism in a food chain occupies what is called a trophic level.

From Textbooks • Jun. 9, 2022

Likewise, a low biomass of organisms can sustain a larger biomass at the next trophic level because the organisms reproduce rapidly and thus supply continuous nourishment.

From Textbooks • Jan. 1, 2015

Autotrophs are critical for most ecosystems: they are the producer trophic level.

From Textbooks • Apr. 25, 2013