1. Biogeochemical Cycles
EQ: Identify and describe the flow of nutrients in each biogeochemical cycle.
Explain the impact that humans have on the biogeochemical cycles.

2. What does biogeochemical mean?

3. BIOGEOCHEMICAL CYCLES

4. ‘Fundamentals’ of biogeochemical cycles
All matter cycles...it is neither created nor destroyed...
As the Earth is essentially a closed system with respect to matter, we can say that all matter on Earth cycles .
Biogeochemical cycles: the movement (or cycling) of matter through a system

5. Matter = elements (carbon, nitrogen, oxygen) or molecules (water) so the movement of matter (for example carbon) between these parts of the system is, practically speaking, a biogeochemical cycle The Cycling Elements: macronutrients : required in relatively large amounts carbon , hydrogen , oxygen , nitrogen , phosphorous sulfur

6. other macronutrients:
potassium , calcium , iron , magnesium micronutrients : required in very small amounts, (but still necessary) boron (green plants) copper (some enzymes) molybdenum (nitrogen-fixing bacteria)

7. ATMOSPHERE

8. LITHOSPHERE

9. HYDROSPHERE

10. ECOSPHERE

11. 6 of the most important cycles are the water, carbon, nitrogen, sulfur, phosphorus and oxygen.
Phosphorous
Sulfur
Oxygen

12. I. The Water Cycle

13. Evaporation -Water changes from liquid to gas
Transpiration -Water evaporates from the leaves into the atmosphere.
Condensation - Water vapor (gas) turns into liquid water forming clouds.
Precipitation -Water droplets become large enough to fall to Earth
-Rain, snow, sleet, or hail
Surface Runoff - Rain, snow, that flows
into streams, rivers, or canals.

14. HYDROLOGIC CYCLE

15. Effects of Human Activities on Water Cycle
We alter the water cycle by:
Withdrawing large amounts of freshwater.
Clearing vegetation and eroding soils.
Polluting surface and underground water.
Contributing to climate change.

16. Water Quality Degradation

17. II. The Carbon Cycle

18. Where does carbon come from?
Natural Sources of
Carbon
Sources of Carbon from Human Activity
Death of plants and animals
Animal waste
Atmospheric CO2
Weathering
Methane gas from cows (and other ruminants)
Aerobic respiration from terrestrial and aquatic life
Burning wood or forests
Cars, trucks, planes
Burning fossil fuels such as coal, oil and natural gas to produce heat and energy.

19. Carbon in Oceans Additional carbon is stored in the ocean.
Many animals pull carbon from water to use in shells, etc.
Animals die and carbon substances are deposited at the bottom of the ocean.
Oceans contain earth’s largest store of carbon.

20. Figure 3.27
Natural capital: simplified model of the global carbon cycle. Carbon moves through both marine ecosystems (left side) and terrestrial ecosystems (right side). Carbon reservoirs are shown as boxes; processes that change one form of carbon to another are shown in unboxed print. QUESTION: What are three ways in which your lifestyle directly or indirectly affects the carbon cycle? (From Cecie Starr, Biology: Concepts and Applications, 4th ed., Pacific Grove, Calif.: Brooks/Cole, © 2000)
Fig. 3-27, pp

22. MARINE CARBON CYCLE

23. TERRESTRIAL CARBON CYCLE

24. Effects of Human Activities on Carbon Cycle
We alter the carbon cycle by adding excess CO2 to the atmosphere through:
Burning fossil fuels.
Clearing vegetation faster than it is replaced.
Figure 3-28

25. III. The Nitrogen Cycle
Where does nitrogen come from?

26. Sources of Nitrogen Inorganic fertilizers Nitrogen Fixation
Animal Residues
Crop residues
Organic fertilizers

27. Forms of Nitrogen Urea  CO(NH2)2 Ammonia  NH3 (gaseous)
Ammonium  NH4
Nitrate  NO3
Nitrite  NO2
Atmospheric Dinitrogen N2
Organic N

28. Roles of Nitrogen
Plants and bacteria use nitrogen in the form of NH4+ or NO3-
It serves as an electron acceptor in anaerobic environment
Nitrogen is often the most limiting nutrient in soil and water.

29. Nitrogen is a key element for
amino acids
nucleic acids (purine, pyrimidine)
cell wall components of bacteria (NAM).

32. Effects of Human Activities on the Nitrogen Cycle
We alter the nitrogen cycle by:
Adding gases that contribute to acid rain.
Adding nitrous oxide to the atmosphere through farming practices which can warm the atmosphere and deplete ozone.
Contaminating ground water from nitrate ions in inorganic fertilizers.
Releasing nitrogen into the troposphere through deforestation.

33. Effects of Human Activities on the Nitrogen Cycle
Human activities such as production of fertilizers now fix more nitrogen than all natural sources combined.
Figure 3-30

34. IV. The Phosphorous Cycle

35. IMPORTANCE OF PHOSPHOROUS CYCLE
1.Phosphorous is an essential nutrient of both plants and animals.
2. It is part of DNA molecules which carry genetic information.
3. It is part of ATP and ADP) that store chemical energy for use by organisms in cellular respiration.
4. Forms phospholipids in cell membranes of plants and animal cells.
5. Forms bones, teeth, and shells of animals as calcium phosphate compounds.

36. PHOSPHOROUS CYCLE

37. HUMAN IMPACTS TO PHOSPHOROUS CYCLE
Humans mine LARGE quantities of phosphate rock to use in commercial fertilizers and detergents. Phosphorous is NOT found as a gas, only as a solid in the earth’s crust. It takes millions to hundreds of millions of years to replenish.
Phosphorous is held in the tissue of the trees and vegetation, not in the soil and as we deforest the land, we remove the ability for phosphorous to replenish globally in ecosystems.
Cultural eutrophication – ad excess phosphate to aquatic ecosystems in runoff of animal wastes from livestock feedlots, runoff of commercial phosphate fertilizers fro cropland, and discharge of municipal sewage.

38. Effects of Human Activities on the Phosphorous Cycle
We remove large amounts of phosphate from the earth to make fertilizer.
We reduce phosphorous in tropical soils by clearing forests.
We add excess phosphates to aquatic systems from runoff of animal wastes and fertilizers.

39. V. The Sulfur Cycle

40. IMPORTANCE OF SULFUR CYCLE
Sulfur is a component of most proteins and some vitamins.
Sulfate ions (SO4 2- ) dissolved in water are common in plant tissue. They are part of sulfur-containing amino acids that are the building blocks for proteins.
Sulfur bonds give the three dimensional structure of amino acids.
Many animals, including humans, depend on plants for sulfur-containing amino acids.

41. SULFUR CYCLE

42. Effects of Human Activities on the Sulfur Cycle
We add sulfur dioxide to the atmosphere by:
Burning coal and oil
Refining sulfur containing petroleum.
Convert sulfur-containing metallic ores into free metals such as copper, lead, and zinc releasing sulfur dioxide into the environment.

43. VI. The Oxygen Cycle

44. The Oxygen cycle

45. PHOTOSYNTHESIS
Photosynthesis: occurs within the chloroplasts of green plants. The photosynthetic membranes are arranged in flattened sacs called the thylakoids.
6CO2 + 12H2O C6H12O6 + 6O2 + 6H2O light
(reactants) (products)
Function: Chemical energy
Storage for cell use

46. CELLULAR RESPIRATION
Cellular Respiration occurs in light simultaneously with photosynthesis. It occurs in the cytoplasm and mitochondria.
It is the reverse reaction of photosynthesis.
Function = chemical energy release
C6H12O6 + 6O2 + 6H2O CO2 + 12H2O chemical energy
(reactants) (products)

47. CULTURAL EUTROPHICATION

48. Cultural Eutrophication & Anoxia
Eutrophication: natural process; over 1000’s of years, lakes fill in with sediment, become marshes then dry land
Cultural Eutrophication: same process, but speeded enormously by loading with “limiting nutrients” (typically P, sometimes N)
Problems associated with cultural eutrophication
Algal blooms
Water anoxia

49. ROCK CYCLE

50. HUMAN IMPACTS ON THE ROCK CYCLE
1. Humans are excavating minerals and removing rock material. It takes millions of years for rock to form.
2. Humans remove sediments for building materials. This removes sediments that may form sedimentary rocks in the future.
3. Humans are filling in wetlands (peatlands), area that will form future coal beds.

51. 1. Which part of the atmosphere is the ozone layer right above. A
1. Which part of the atmosphere is the ozone layer right above? A. Stratosphere B. Troposphere C. Mesosphere D. Thermosphere 2. How long does it take rock formations to form? A. 1,000 years B. 10,000 years C. 100,000 years D. 1,000,000 years E. 10,000,000 years 3. What is cultural eutrophication good for? A. Fish B. Dissolved Oxygen in the lake C. algae D. clear lake
1. b 2. d 3. c

52. Works Cited http://science.pppst.com/carboncycle.html
westernreservepublicmedia.org/earthmotion3/images/Carbon_Cycle.ppt
clima-dods.ictp.it/d3/annalisa/ocean_sv/lecture1.ppt