1. Biogeochemical Cycling

2. HNO3
NOx
SOx
Motivation

3. USGS

6. Many scientific studies have identified a relationship between elevated levels of fine particles and increased illness and premature death from heart and lung disorders, such as asthma and bronchitis.

7. Brief lesson in soil biology

12. Nutrient cycling takes three primary modes…

13. Figure 22.1

14. The Nitrogen Cycle (1012 g N/yr)
Figure 22.8
The Nitrogen Cycle (1012 g N/yr)

16. Figure 22.7

17. Nitrogen saturation impacts North American ecosystems
Brief lesson in soil biology…

19. Figure 22.10
Phosphorus cycling

20. Figure 22.9
Phosphorus cycling

21. Pools & Fluxes in the Calcium Cycle

22. Sulfur cycle, important but still being worked out…
Figure 22.12
Sulfur cycle, important but still being worked out…

23. Biogeochemical cycling