1. Biochemical Cycles July 9, 2009

2. Lake Washington Humans knowingly and unknowingly alter the natural cycling of chemicals to the detriment of the environment Seattle began disposing of treated sewage into freshwater Lake Washington in the 1930s. Result?

3. Biochemical Cycles A biochemical cycle is the complete path a chemical takes through Earth’s 4 spheres: lithosphere, hydrosphere, atmosphere, and biosphere

4. Cycling of a Chemical in an Ecosystem

5. Biogeochemicals: Limiting Factors 103 known elements, 24 required for life processes Macronutrients Micronutrients Silver, Arsenic, Radon, Lead, Uranium Elements with a gas phase can be cycled more quickly

6. Geologic Cycle Rocks and soils continuously created, maintained, changed, and destroyed by physical, chemical, and biological processes Tectonic cycle Plate tectonics

7. Geologic Cycle

8. Plate Boundaries Divergent plate boundary – Convergent plate boundary – Transform fault boundary –

9. Plate Boundaries

10. Hydrologic Cycle Hydrologic Cycle – the cycling of water between the atmosphere, lithosphere, biosphere, and hydrosphere Drainage basin –

11. Hydrologic Cycle

12. Rock Cycle Rock cycle – Igneous rocks – Sedimentary rocks – Metamorphic rocks –

13. Rock Cycle

14. Carbon Cycle

15. Carbon Sink Carbon-silicate cycle –

16. Nitrogen Cycle Nitrogen fixation – Denitrification

17. Nitrogen Cycle

18. Phosphorus Cycle