Biogeochemical Cycles

1
Biogeochemical Cycles

• Water, Carbon, Nitrogen, Phosophorus

2
Water Cycle

• Crucial
• 3 important processes
• Evaporation
• Adds water vapor to atmosphere
• Caused by heat
• Transpiration
• Water evaporates from leaves of plants
• Causes plants to take in water
• Breathe, sweat, excrete
• Precipitation
• Leaves atmosphere
• When saturated occurs

3
Water Cycle
4
Carbon Cycle

• Photosynthesis and Cellular Respiration are
  basis.
• Plants use carbon dioxide to make carbohydrates.
• Byproduct of cellular respiration carbon
  dioxide
• Decomposers release carbon dioxide into
  atmosphere.
• Humans influence cycle by burning fossil fuels
  and organic matter.

5
Carbon Cycle
6
Nitrogen Cycle

• Nitrogen gas makes up 78 of the atmosphere.
• Plants can only use nitrogen in the form of
  nitrate. (Nitrogen Fixation)
• Nitrogen-fixing bacteria transforms nitrogen into
  a usable form.
• Decomposers release nitrogen as ammonia, which in
  the soil is known as ammonium ammonification.
• Soil bacteria takes up ammonium and oxidize it
  into nitrites and nitrates nitrification.
• Denitrification anaerobic bacteria breaks down
  nitrates and releases nitrogen gas.

7
Nitrogen cycle
8
Phosphorus Cycle

• Needed to form bones, teeth, and parts of
  molecules.
• Plants get phosphorus from soil and water.
• Animals get phosphorus from eating plants and
  animals.
• Slow cycle, doesnt occur in atmosphere.

9
Phosphorus Cycle
10
Oxygen Cycle

• Oxygen is found in
• Rocks as oxide minerals
• The atmosphere as oxygen and ozone
• Biosphere when it is exchanged between plants and
  animals during photosynthesis and cellular
  respiration.

11

• Main source of oxygen is produced by plants and
  algae.