Question

Construct a pyramid of biomass starting with phytoplankton, label its three trophic levels. Is the pyramid upright or inverted? Justify your answer.

Answer 1

1. In an aquatic ecosystem, the biomass pyramid is inverted.  Phytoplankton (producers) have lower biomass than zooplankton (primary consumers), but tiny fish (secondary consumers) have higher biomass.
2. Phytoplankton have strong reproductive rates and are quickly devoured, while zooplankton and fish have longer lifespans, resulting in an inverted biomass pyramid.