Biogeochemical Cycles

1
Biogeochemical Cycles
2
Hydrologic Cycle
http//www.groundwater.org/kc/kc.html, June 14,
2007
A model that shows the movement of water between
the hydrosphere, lithosphere, atmosphere, and
biosphere.
3
Hydrologic Cycle Processes

• Evaporation-change in water from liquid to gas
• Transpiration-evaporation of water from leaves of
  plants
• Condensation-change in water from gas to liquid
• Precipitation-deposit of water in either liquid
  or solid form
• Runoff-movement of water across land surfaces
• Infiltration-water soaking through the subsurface
  of the earth
• Percolation-water moving down through layers of
  soil and rock
• Groundwater-water beneath the surface and beyond
  the soil-root zone

4
Why is the water cycle important?

• What is the source of energy for the water cycle?
  
• Where on earth does the greatest amount of
  evaporation occur?
• How is the earths water cycle balanced?
• What roles are played by groundwater?

5
Nitrogen Cycle
http//www.windows.ucar.edu/tour/link/earth/clima
te/images/nitrogencycle_jpg_image.htmleduelem,
June 14, 2007
A model that shows the movement of nitrogen
between the hydrosphere, lithosphere, atmosphere,
and biosphere.
6
Nitrogen Cycle
http//www.physicalgeography.net/fundamentals/9s.h
tml, June 14, 2007
A model that shows the movement of nitrogen
between the hydrosphere, lithosphere, atmosphere,
and biosphere.
7
Nitrogen Cycle Processes

• Nitrogen Fixation-N2 is changed into ammonia
  (NH3) by bacteria in soil, legumes, or lightning
• Nitrification-ammonia (NH3) is changed to nitrite
  (NO2) and then nitrate (NO3) by bacteria in soil
• Ammonification-Release of ammonia by decomposers
  (bacteria)

8
Nitrogen Cycle Processes 2

• Denitrification-Nitrate (NO3) changed back to
  atmospheric nitrogen (N2) by bacteria.
• Eutrophication-Addition of excess nutrients to
  bodies of water. This causes excessive plant
  growth and oxygen depletion.
• Release of nitrogen compounds (nitrogen oxide
  (NO), nitrogen dioxide (NO2), and nitrous
  oxide(N2O)) into the atmosphere by human activity
  including combustion of fossil fuels, farming of
  animals, production of sewage, and fertilizer
  use.

9
Nitrogen Fixing Organims
Legumes
Bacteria
http//en.wikipedia.org/wiki/Cyanobacteria,
August 8, 2008
Others--Alder
http//en.wikipedia.org/wiki, August 8, 2008
10
Why is the nitrogen cycle important?

• What is the purpose of an aquarium filter, and
  how does it work?
• What happens in a compost pile or bin?
• What form of nitrogen do most plants use?
• What group of organisms plays a global role in
  returning nitrogen to the atmosphere?

11
Phosphorus Cycle
http//www.enviroliteracy.org/article.php/480.html
, June 14, 2007
A model that shows the movement of phosphorus
between the hydrosphere, lithosphere, atmosphere,
and biosphere.
12
Phosphorus Cycle
http//arnica.csustan.edu/carosella/Biol4050W03/fi
gures/phosphorus_cycle.htm, June 14, 2007
13
Phosphorus Processes

• Produced by weathering rock
• Taken up by plants
• Dissolves in water
• Eaten by animals or taken in through drinking
  water-used for ATP, DNA, and RNA.
• Returned to the soil or water by decomposing
  tissues

14
Phosphorus Cycle

• Phosphorus does not easily achieve a gaseous
  state and therefore the atmosphere is not
  involved in the phosphorus cycle.
• Phosphorus is easily dissolved and is returned to
  the ocean through runoff. It sinks to the bottom
  of the ocean and becomes lost because it will
  be unavailable for millions of years while
  sedimentation is occurring on the ocean floor.

15
Why is the phosphorus cycle important?

• What is the main reservoir of phosphorus?
• How do we use phosphorous in our bodies?
• How do plants use phosphorous?

16
Carbon Cycle
http//www.physicalgeography.net/fundamentals/9r.h
tml, June 14, 2007
A model that shows the movement of carbon between
the hydrosphere, lithosphere, atmosphere, and
biosphere.
17
Carbon Cycle Processes

• Carbon is stored in living and non-living
  components of the ecosystem.
• Carbon moves from the atmosphere to plants
  through photosynthesis.
• Carbon moves from plants to animals when animals
  eat plants.
• Carbon moves from plants and animals to the
  ground when organisms die and decomposers break
  down the remains.
• Carbon moves from living things to the atmosphere
  through respiration.
• Carbon moves from fossil fuels to the atmosphere
  and the oceans when fossil fuels are burned.

18
Carbon Movement by Plants
Through the process of respiration living
organisms breakdown glucose or other
carbohydrates releasing carbon dioxide into the
atmosphere.
Respiration
__________________________________________________
____________
Plants use the process of photosynthesis to
convert the suns energy into chemical energy to
be used by living organisms. Carbon dioxide is
consumed in this process and carbohydrates are
produced.
Photosynthesis
http//www.usoe.k12.ut.us/curr/science/core/8thgrd
/sciber8/matter/html/photosyn.htm, June 26, 2007
19
Why is the carbon cycle important?

• How are fossil fuels related to the carbon cycle?
• Why do we exhale carbon dioxide?
• What is the major reservoir for carbon?
• How does carbon return to the atmosphere?

20
Oxygen Cycle
http//water.me.vccs.edu/concepts/oxycycle.html,
June 14, 2007
A model that shows the movement of oxygen between
the hydrosphere, lithosphere, atmosphere, and
biosphere.
21
Oxygen Cycle
Most living organisms need oxygen to release the
energy stored in food. The process through which
this energy is released is called respiration.
Respiration is the reason we must breathe oxygen
to live. Respiration consumes oxygen and
released carbon dioxide.
Respiration
__________________________________________________
____________
Plants use the process of photosynthesis to
convert the suns energy into chemical energy to
be used by living organisms. Carbon dioxide is
consumed in this process. Oxygen is released in
the process.
Photosynthesis
http//www.usoe.k12.ut.us/curr/science/core/8thgrd
/sciber8/matter/html/photosyn.htm, June 26, 2007
22
Photosynthesis and Respiration
http//www.accessexcellence.org/RC/VL/GG/ecb/photo
synthesis_respiration.html, June 26, 2007
23
Oxygen Cycle
http//www.fossweb.com/resources/pictures/48825681
7.html, June 14, 2007
A model that shows the movement of oxygen between
the hydrosphere, lithosphere, atmosphere, and
biosphere.
24
Why is the oxygen cycle important?

• Why do we need oxygen to live?
• Do plants need oxygen?
• What percentage of the earths atmosphere is
  oxygen? What would happen if oxygen levels
  increased in the earths atmosphere?
• What percentage of the earths crust is oxygen?

25
Find astrosomething site

• Use slate

26
Law of Conservation of Energy

• Energy can not be created or destroyed, but can
  change its form.

27
Movement of Energy on Earth

• Energy flows in one direction among living
  organisms. It is not recycled.
• Energy for all photosynthesis comes from the sun.
• As this energy is transferred from one organism
  to another, energy is lost to the environment,
  usually as heat.

http//regentsprep.org/Regents/biology/units/ecolo
gy/energy.cfm, June 26, 2007
28
Law of Conservation of Matter

• Matter can not be created or destroyed, but can
  change its form.

29
Nutrients cycle, Energy flows
Solar Energy
Heat
Heat
Abiotic Chemicals (N, C, O, P, H2O)
Heat
Decomposers (Bacteria, Fungus)
Producers (Plants)
Consumers (Herbivores, Carnivores)
Heat
Heat
30
Movement of matter and energy in ecosystems.

• Matter is not created or destroyed. It is
  recycled in different forms.
• Energy is not created or destroyed. It changes
  forms in an ecosystem and is released into the
  atmosphere as heat. It is NOT recycled. When it
  is lost to the atmosphere it cannot be recaptured
  for use as energy for food.