1. Chapter 2: Energy Flow and Nutrient Cycles Support Life in Ecosystems

3. Today
Virtual lab
Diagram page 76 textbook
Nutrient cycling (CARBON)
Stores
6 main processes C is cycled
Anthropogenic effects
Workbook pages

4. A 54-year old sealed terrarium (planted in 1960) no fresh air or water

5. 2.2 Nutrient Cycles in Ecosystems
Earth’s biosphere acts like a sealed terrarium where nutrients and wastes are recycled
Carbon, nitrogen and phosphorus cycles move nutrients in and out of terrestrial and aquatic ecosystems
Where does the water you drink come from?

6. 2.2 Nutrient Cycles in Ecosystems
Human activities can upset the natural balance of nutrient cycles:
- land clearing
- agriculture
- industry
- motorized transportation

7. Nutrient Cycling
Nutrients: chemicals that are needed for plant and animal growth and other life processes.
Are accumulated in atmosphere, oceans, and land masses
Stores: location of nutrient accumulation

8. Nutrient Cycling Nutrient Cycling: movement in and out of stores
Caused by biotic and abiotic processes
Cycles are near balance (input = output)
You need to know about C, N, & P cycles
But O and H are also needed for life

9. Carbon Cycle

10. Carbon Stores All living things contain carbon in their cells
How carbon is stored:
Short term stores
- vegetation on land, in oceans
- animals and decaying OM in soil
- atmosphere as CO2
- top layers of ocean

11. Carbon Stores Long-term stores: - intermediate and deep oceans
- coal deposits
- marine deposits and sedimentary rock

12. Amount of C /Gigatonnes
Carbon Stores
Store
Amount of C /Gigatonnes
Marine sediments and sedimentary rock to
Oceans (intermediate/deep) to
Coal Deposits
3 000
Soil and organic matter
1 500 to 1 600
Atmosphere
750
Terrestrial Vegetation
540 to 610
Oil and Gas Deposits
300
Giga = 1 billion or 109
Where is most carbon stored?

13. Carbon Stores Sedimentation: Traps many long-term carbon stores
Layers of soil/decomposing OM get buried
turn into rock/coal/oil/gas by SLOW geological processes

14. Carbon Stores
Limestone (CaCO3 ) forms from shell deposits on ocean floor
Long-term carbon stores
are aka carbon sinks

15. Carbon Cycle Carbon is cycled through ecosystems by: Photosynthesis
Cellular respiration
Decomposition

16. #1) Photosynthesis Sun + 6H20 + 6CO2 → C6H12O6 + 6O2
chemical reaction in plants and
cyanobacteria where sunlight
(solar energy) is used to make
glucose (chemical energy)
Sun + 6H20 + 6CO2 → C6H12O6 + 6O2
(sun + water + carbon dioxide → sugar + oxygen)

17. #1) Photosynthesis recycles carbon and oxygen through ecosystems
By eating plants, consumers obtain energy and take carbon into their cells.

18. Giga = billion

19. #2) Cellular Respiration
Opposite of photosynthesis
chemical reaction in mitochondria of cells where oxygen is used to liberate energy from glucose.
6O2 + C6H12O6 -> 6CO2 + 6H2O + energy

20. Giga = billion

21. #3) Decomposition the breaking down of dead organic matter
Decomposers (bacteria + fungi) convert organic molecules (carbohydrates) back into carbon dioxide.

22. Giga = billion

23. Today Nutrient cycling (CARBON) Review 6 main processes C is cycled
What are YOU doing?
PHosphorUs and Nitrogen
(Phun with a P-H!)

24. You’re the next contestant!
One lucky volunteer gets to click the link and be the host while I check WB 24-26
You have 10 minutes…

26. Other ways carbon is cycled
#4) Ocean processes (CO32-) sediments, marine organisms remember CaCO3! We made some in a lab. #5) Volcanic eruptions release CO2 #6) CO2 is rapidly released during forest fires (slowly for decomposing trees)

27. Giga = billion

28. Human activities and the carbon cycle
Industry, motorized transportation, land clearing
Industrial revolution (160 yrs ago) CO2 levels increased by 30% from increase of fossil fuel burning
Increase in CO2 in the previous ya was 1-3%
We release C from long-term
stores FAST (coal, oil, gas)

29. Anthropogenic effects
Burning fossil fuel reintroduces C to
the cycle that was removed in a long term
store
CO2, a greenhouse gas, is the most common form of carbon
absorbs heat in atm.
Contributes to global climate change

30. Anthropogenic effects?
Clearing land reduces amount of carbon taken from atmosphere by plants during photosynthesis
Farm plants remove CO2, but less than natural vegetation

31. Agriculture: cows are carbon culprits
Our obsession with cows is causing almost 10% of global warming emissions
Cows release methane from digestion (23x stronger than CO2)
Feed is not environmentally friendly

32. Giga = billion

33. Breaking down the carbon cycle

35. Carbon cycle

36. Today Nutrient cycling (CARBON) Review 6 main processes C is cycled
What are YOU doing?
PHosphorUs and Nitrogen
(Phun with a P-H!)
BONUS CHALLENGE… tell me what you learned about nutrient cycling from THE link that was NOT covered in class (5 marks maximum, handed in at beginning of next class)