A marine kelp forest ecosystem contains giant kelp (producers), sea urchins (primary consumers), sea otters (secondary consumers), and marine decomposers. Describe how carbon is cycled between these living organisms (biotic components) and the abiotic environment (the water and atmosphere).

In your answer, you should:

• Explain how carbon enters the biotic component of this marine ecosystem.
• Explain how carbon is transferred between different trophic levels.
• Explain the biological processes that return carbon back to the abiotic environment.