🎒 Base knowledge and understanding

✅ Tasks

🌿 Content

🔑 Key terms for revision

🎯 Learning intentions

By the end of this lesson, you should be able to:

1. Apply systems terminology (stores, flows, transfers, transformations, feedback loops) to the carbon cycle
2. Explain how NP and GP relate to carbon sequestration in ecosystems
3. Evaluate the carbon cycle as an example of a system approaching or crossing tipping points
4. Connect the carbon cycle to sustainability and environmental value systems

Part 1: The Carbon Cycle as a System

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1.2.2 A systems approach is a holistic way of visualising a complex set of interactions, and it can be applied to ecological or societal situations.

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Applying systems vocabulary to the carbon cycle

In Topic 1.2, you learned that systems have stores (represented as boxes) and flows (represented as arrows). The carbon cycle is a perfect example of this.

Stores in the carbon cycle:

• Atmosphere (800 GtC)
• Terrestrial biosphere (plants, animals, soil: ~2,500 GtC)
• Oceans (~38,000 GtC)
• Fossil fuels (~10,000 GtC)
• Lithosphere/sediments (>60,000,000 GtC)

Flows in the carbon cycle:

• Photosynthesis (~120 GtC/year)
• Respiration and decomposition (~120 GtC/year)
• Ocean-atmosphere exchange (~90 GtC/year each way)
• Fossil fuel combustion (~9 GtC/year)

1. Complete the table below:

1. Why is the distinction between transfers and transformations important for understanding the carbon cycle?

Feedback loops in the carbon cycle