1. Where is the main reservoir of P located?
2. Name the processes at A
3. What do the downwards pointing arrows from TL2,3,4 represent?
4. Name 3 uses of P in living cells.
5. D represents a man made intervention-what does the arrow pointing up to D represent?
6. What does D represent?
7. What does the downward pointing arrow from D represent?
8. What process does C represent?
9. How else does man increase environmental P levels?
10. What effect does P pollution have?
11. Which is the most globally mobile element - phosphorus or carbon? Explain why.
12. What does B represent?

1. In rocks and sediments
2. Weathering, uplift and erosion.
3. Excretion and death and decay leading to P entering the soil pool.
4. In protein, in DNA, in ATP. If you can't remember what ATP is for-check up now!)
5. Quarrying and extraction of P
6. Processing of P into usable substances.
7. Application of P fertiliser to soil for crops.
8. P being carried in streams and rivers to the sea.
9. Pollution from (e.g.) detergents, untreated sewage, industrial effluents.
10. Acts as nutrient-may lead to eutrophication.
11. Carbon. Because most phosphorus is locked up in rocks which take millennia to recycle. In the carbon cycle by comparison, there is a substantial atmospheric component meaning that the carbon you breathe out today may form part of a kangaroo's paw within a relatively short period.
12. Waterborne P being deposited in marine sediments.

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©David Funge 2002.