Transcript zzz Sept 28 day thirteen

Nutrient Cycles

Certain materials are cycled through
ecosystems to be used over and over, they are
called nutrients

Examples of these nutrients are carbon,
nitrogen and phosphorus

When we disrupt these cycles we affect the
ecosystems that they are a part of
The Carbon Cycle
Carbon is an essential element for all organisms. It is
found in different forms in all four spheres of the
earth. Six factors contribute to its cycling:
1. Photosynthesis - Plants use sunlight to “capture”
carbon dioxide from the atmosphere (as CO2) to
make sugars. The chemical reaction is:
light
+
6CO2
+
6H2O

(Sun’s (carbon dioxide (water (produces)
energy) from the air)
from
the soil)
C6H12O6
(sugar
to make
leaves…)
+
6O2
(oxygen
released
to the air)
6 Factors that contribute to the
carbon cycle
2. Respiration – Process by which animals and plants
(in the dark) use sugars to make energy and CO2.The
chemical reaction is:
C6H12O6
(sugars
from food)
+ 6O2
(breath
it in)

6CO2
(breath
it out)
+
6H2O +
(water in
the body)
energy
(needed grow,
move…)
What do you notice about these two reactions?
Answer: They are opposite! Plants produce the sugars and oxygen that
animals need. Animals need plants to survive.
6 Factors that contribute to the
carbon cycle
3. Food Chain: Carbon is also passed on from producers to
consumers and moves up the food chain.
4. Decay: Decomposers break down dead plant and animal
material. Some of the carbon is released as CO2 into the
atmosphere some of it enters the ground.
6 Factors that contribute to the
carbon cycle
5. Combustion: During the combustion of fossil fuels (oil,
gasoline, natural gas) and forest fires, CO2 is released
into the atmosphere.
6. Carbon reservoirs: Carbon is stored in different
parts of earth’s four spheres (eg. much CO2 is dissolved
in the oceans, carbon is stored in the earths crust as coal
and fossil fuels)
Human impact on the carbon cycle
How have humans impacted the carbon cycle?
What are the consequence of this?
Diagram of the carbon cycle