In a pyramid of energy, the amount of energy at each successive trophic level is approximately 10% of the previous level. If the net primary productivity of an ecosystem is 10,000 kcal/m²/year, what is the approximate energy available to tertiary consumers in this ecosystem?
Correct: C
The pyramid of energy follows the 10% rule (Lindeman's ten percent law). Energy at the producer level is 10,000 kcal/m²/year. Primary consumers receive about 10% of that, i.e., 1,000 kcal/m²/year. Secondary consumers receive 10% of primary consumers, i.e., 100 kcal/m²/year. Tertiary consumers receive 10% of secondary consumers, i.e., 10 kcal/m²/year. Therefore, the energy available to tertiary consumers is approximately 10 kcal/m²/year.