Which of the following would have the largest biomass in a terrestrial ecosystem?

• A. Secondary consumers (carnivores)
• B. Producers (such as grasses and trees)
• C. Tertiary consumers (top predators)
• D. Primary consumers (herbivores)

Answer: (B)

Verified step by step guidance

1. Understand the concept of biomass: Biomass refers to the total mass of living organisms in a given area or ecosystem at a specific time. It is typically measured in terms of dry weight and represents the energy available at each trophic level.
2. Review the trophic levels in a terrestrial ecosystem: Producers (such as grasses and trees) form the base of the food chain, followed by primary consumers (herbivores), secondary consumers (carnivores), and tertiary consumers (top predators). Energy and biomass decrease as you move up the trophic levels.
3. Apply the 10% rule of energy transfer: Only about 10% of the energy at one trophic level is transferred to the next level. This means producers have the most energy and biomass, while tertiary consumers have the least.
4. Consider the role of producers: Producers are responsible for converting solar energy into chemical energy through photosynthesis. They form the foundation of the ecosystem and support all other trophic levels, resulting in the largest biomass.
5. Conclude that producers have the largest biomass: Since producers are the primary source of energy and support all other levels, they have the largest biomass in a terrestrial ecosystem compared to primary, secondary, and tertiary consumers.