Topic Summary

Topic 2.3, “Biogeochemical Cycles” focuses on the carbon cycle and the nitrogen cycle. The nitrogen cycle is HL-only content.

Lessons

Lesson 1: The Carbon Cycle

Presentation

Lesson 2: The Nitrogen Cycle (HL)

Presentation

Theory of Knowledge

  • Does the systems approach to looking at complex systems, such as the carbon cycle, improve or understanding, or does it oversimplify and weaken knowledge?
  • Considering industrial processes such as the Haber process providing liquid fertilisers, does modern technology weaken our understanding of ecosystem services, such as natural nitrogen fixation?