In a lake ecosystem the net primary productivity of producers is $1200\ \text{g C m}^{-2}\ \text{yr}^{-1}$. The average trophic transfer efficiencies are 10 % from producers to primary consumers and 15 % from primary to secondary consumers. The biomass of tertiary consumers is measured as $8\ \text{g C m}^{-2}$.

(a) Determine the unknown trophic transfer efficiency from secondary to tertiary consumers.

(b) Calculate the expected biomass of primary consumers.

Question

In a lake ecosystem the net primary productivity of producers is $1200\ \text{g C m}^{-2}\ \text{yr}^{-1}$. The average trophic transfer efficiencies are 10 % from producers to primary consumers and 15 % from primary to secondary consumers. The biomass of tertiary consumers is measured as $8\ \text{g C m}^{-2}$.

(a) Determine the unknown trophic transfer efficiency from secondary to tertiary consumers.

(b) Calculate the expected biomass of primary consumers.

Accepted Answer

Transfer efficiency ≈ 44 %; primary‑consumer biomass = 120 g C m^{-2}

Gce Model Questions Vol1 2023 Biology Question 34

Answer Options

About This Question

Master the Exam!