Tundra
- 14. Water Cycle in Tundra Permafrost Soil Snow Precipitation Seepage River Ocean Evaporation Condensation Accumulation
- 15. Nitrogen Cycle in Tundra Permafrost Death and Waste Nitrogen Fixation Decomposers Amonification Ammonia (NH3) Nitrification Nitrates Dentrification Nitrogen Gas Assimilation
- 16. Carbon Cycle in Tundra Photosynthesis Cellular Respiration Permafrost Soil Death or Decomposition Fossil Fuels Combustion Carbon Dioxide (CO2)