Energy Transfer and Productivity in Ecosystems

Flashcards covering key concepts related to energy transfer, productivity, and thermodynamics in ecosystems.

What are the units used to measure energy in ecosystems?

Calories, kilocalories, joules, or kilojoules.

What is the ecological efficiency of most ecosystems?

Approximately 10%.

What does the first law of thermodynamics state?

Energy is neither created nor destroyed.

What does the second law of thermodynamics state regarding energy transfer?

Energy transfer can never be 100% efficient; some energy is always lost as heat.

What process do producers (autotrophs) use to capture energy?

Photosynthesis.

What is the term for the total energy captured by producers in an ecosystem?

Gross primary productivity (GPP).

What is net primary productivity (NPP)?

The amount of energy left after the energy used by producers for respiration is subtracted from GPP.

How much of the net primary productivity can consumers (heterotrophs) typically use?

About 10%.

Why do most food chains and webs not include many trophic levels?

Due to the significant energy loss at each trophic level.