FOCUS QUESTION

How does nitrogen cycle between the air, soil and living things?

The map breaks this topic into its core concepts, connected by labeled relationships. Each link is written so it can be read as a complete statement — not just an unlabeled line between boxes.

Concepts and relationships

  • Nitrogen Cycle circulates Atmospheric N₂.
  • Atmospheric N₂ converted by Nitrogen Fixation.
  • Nitrogen Fixation produces Nitrates.
  • Nitrates absorbed by Plants.
  • Plants return through Decomposition.
  • Decomposition feeds Nitrification.
  • Nitrification forms Nitrates.
  • Nitrates reversed by Denitrification.
  • Denitrification releases Atmospheric N₂.

How to read this map

Begin with atmospheric N₂, follow fixation into nitrates that plants absorb, then trace decomposition and nitrification back around the loop.

Learning objectives

  • Name the main stages of the nitrogen cycle.
  • Explain nitrogen fixation and nitrification.
  • Describe how plants obtain nitrogen.
  • Connect decomposition and denitrification to the cycle.
Editorial note: Stage names and transitions were checked against standard secondary-school biology descriptions. Sources: OpenStax Biology 2e — Biogeochemical Cycles.