How much energy is transferred from one trophic level to the next?

Concept

Energy flow through an ecosystem is unidirectional. At each trophic transfer, organisms use most of the available energy for metabolism, movement, growth, and respiration.

Lindeman’s ten-percent law states that, on average, only about 10% of the energy available at one trophic level is transferred to the next higher trophic level; the rest is largely dissipated as heat and through life processes.

Application

1. Take 100 energy units as the energy available at a trophic level.

2. Apply the ten-percent law: transferred energy = 10% × 100 = 10 energy units.

3. Therefore, the fraction transferred to the next trophic level is 10%.

Cross-check and contrast

Repeating the calculation from 1,000 energy units gives 100 units at the next level, again a 10% transfer.

• A 5% transfer would pass only 5 of every 100 energy units.

• A 15% transfer would pass 15 of every 100 energy units.

• More than one of the listed percentages cannot describe the single transfer fraction specified by the ten-percent law.

• None of the above does not apply because 10% is one of the listed values.

Thus, about 10% of the energy is transferred from one trophic level to the next.