Download cycles of matter

Carbon Cycle
Chapter 5-Section 2: p. 132, also p. 125 & 128
Reservoirs of Carbon
Forms of carbon stores or storage places
Reservoirs of Carbon
Where is carbon?
 The
major reservoir (storage) of
carbon is carbon dioxide (CO2) in
the atmosphere
Reservoirs of Carbon
Where is carbon? Other
reservoirs:
 Organic
matter (makes up living
things): proteins, fats,
carbohydrates
 Fossil fuels (buried remains of
organisms)
Processes of Carbon
How carbon is transformed & cycled through an ecosystem
Processes of Carbon
Important processes that cycle
carbon into living organisms:
• Photosynthesis
• Heterotrophy (food
chain)
Processes of Carbon
Photosynthesis
 Autotrophs
use photosynthesis to
convert light energy (sun) into
chemical energy (sugar; glucose)
Processes of Carbon
The Chemical Equation for
Photosynthesis is…
6CO2 + 6H2O + light  C6H12O6 + 6O2
Note: What molecules of carbon are shown above?
Don’t forget, autotrophs…
 Include
plants, algae, bacteria
 Contain chlorophyll (pigment to
absorb light)
 Are producers
 Form the base of ecological pyramids
Processes of Carbon
Heterotrophy
 As organisms consume food, energy
travels from one organism to another
 So does carbon, but it’s transformed
(changes form) again
 Heterotrophs have less energy
available to them from autotrophs
Processes of Carbon
Processes that cycle carbon out
of living organisms:
• Respiration
• Burning fossil
fuels
• Decay &
decomposition
Click here to view animation
Processes of Carbon
Respiration (cellular)
 Chemical reaction to break down
carbohydrates
 It’s how organisms get energy out
of the sugars
 ALL ORGANISMS RESPIRE!!!
(plants too)
Processes of Carbon
The Chemical Equation for
Respiration is…
C6H12O6 + 6O2 6CO2 + 6H2O + ATP
(ATP is an energy molecule)
Note: What molecules of carbon are shown above?
Processes of Carbon
Short-term
 Photosynthesis
& respiration
Long-term (always think the “rock cycle”)
 Carbon
found in bones and shells
for limestone rocks
 Deposits of coal, oil and natural gas
(fossil fuels)
Molecules of Carbon
Forms of carbon (compounds, molecules, atoms)
Molecules of Carbon
In the atmosphere

Carbon dioxide (CO2)
In living things

Glucose (C6H12O6) or sugar/carbohydrates,
fats, proteins
Underground

Rocks (limestone) and fossil fuels, such as
coal, oil, natural gas
Nitrogen Cycle
Chapter 5-Section 2: p. 134
Reservoirs of Nitrogen
Where is nitrogen found?
 The major reservoir of nitrogen
is the atmosphere as nitrogen
gas (N2)
Reservoirs of Nitrogen
Where is nitrogen found?
Other reservoirs:
 In the ground as nitrates
(fertilizers)
 In proteins that make up
organisms
Processes of Nitrogen
How nitrogen is transformed & cycled through an ecosystem
Processes of Nitrogen
Important processes that cycle
nitrogen into living organisms:
 Nitrogen fixation
 Absorption
 Heterotrophy (food chain)
Processes of Nitrogen
Nitrogen Fixation
 Bacteria that live on roots of
legumes (bean plants like
soybean or clover) convert
atmospheric N2 to a “fixed”
form that plants can absorb
 I.e. it makes fertilizer
Processes of Nitrogen
Heterotrophy
 Plants absorb “fixed” nitrogen
from the soil (fertilizer)
 As organisms consume food,
nitrogen travels from one
organism to another is used to
make proteins
Processes of Nitrogen
Processes that cycle nitrogen
out of living organisms:
 Excretion
 Decomposition
 Denitrification
Click here to view animation
Processes of Nitrogen
Excretion
 Animals release nitrogenous
wastes in the form of urine or
dung
 Also known as ‘ammonification’
Processes of Nitrogen
Decomposition
 Bacteria, insects, fungi break
down wastes and decaying
plants and animals
 Release Nitrogen back into the
soil
Processes of Nitrogen
Denitrification
 Bacteria transform a small
amount into nitrogen gas, which
returns to the atmosphere
Processes of Nitrogen
Short-term
 Fixation, absorption
decomposition
&
Molecules of Nitrogen
Forms of nitrogen
Molecules of Nitrogen
In the atmosphere

Nitrogen gas (N2)
In living things

Proteins
Underground

Ammonium nitrates (fertilizers)
Phosphorus Cycle
Chapter 5-Section 2: p. 135
Reservoirs of Phosphorus
Forms of phorphorus stores or storage places
Reservoirs of Phosphorus
Where is phosphorus found?

The major reservoir of
phosphorus is in salts & rock
sediment

Other reservoirs include
waterways (washed from eroded
rocks and emptied in oceans)
Processes of Phosphorus
How phosphorus is transformed & cycled
Processes of Phosphorus
How phosphorus cycles into
living organisms:
• Erosion of rocks
• Absorption
• Heterotrophy (food chain)
Processes of Phosphorus
Erosion
 Small
amounts of phosphorus
dissolve in soil and water
Processes of Phosphorus
Heterotrophy

Plants absorb phosphates from the
soil

As organisms consume food,
phosphorus travels from one
organism to another and is used to
make bones and teeth
Processes of Phosphorus
How phosphorus cycles out of
living organisms:
• Excretion
• Decomposition
Click here to view animation (narrated choice available)
Processes of Phosphorus
Short-term
 Absorption
& decomposition
Long-term (always think the “rock cycle”)
 Phosphorus
cycle mainly involves
reserves underground and on the
bottom of the ocean
Molecules of Phosphorus
Forms of phosphorus (compounds, molecules, atoms)
Molecules of Phosphorus
In living things

Cells of living things, bones, teeth and DNA
Underground

Rocks (limestone) and ocean sediment
(phosphates)
Key Points
Carbon makes up the basis for all organic life
 Most nitrogen is unusable in the atmosphere;
we all depend on bacteria to “fix” it for us
 Phosphorus does not cycle through the
atmosphere
 Long-term part of each cycle includes forming
and eroding rock; whereas the short-term part
of each cycle is the movement between living
things

Humans Affects
Chapter 5-Section 2: p. 133, 136
How humans affect cycles
Carbon cycle

By burning fossil fuels we release carbon
into the atmosphere (about ½ remains in
the atmosphere)
Phophorus & Nitrogen cycles
Excessive amounts of fertilizer can cause too
much algae growth, which use up oxygen
 Nitric oxides are released when fossils fuels
are burned and mix with water vapor to
form acid rain
