Transcript biogeochemical cycle

CYCLES OF MATTER
The Water Cycle
 Nutrient Cycles
 The Carbon Cycle
 The Nitrogen Cycle
 The Phosphorus
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The WaterCycle
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Life depends on the recycling of chemicals.
Chemicals pass back and forth between
organic matter and the abiotic components.
A biogeochemical cycle is the cycling of
elements of ecosystems, chemical compounds,
and other forms of matter which are passed
from one organism to another and from one
part of the biosphere to another.
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It connects biological, geological and chemical
aspects of the biosphere.
Water Chemical Properties
+
+
H
H
Two atoms of hydrogen
One atom of oxygen
o
-
What Does Water Move Between?
Water moves between the land,
oceans, and atmosphere.
 Water vapor is water molecules
that enter the atmosphere as a gas
when they evaporate from the
ocean or other bodies of water
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Evaporation
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The process by
which water
changes from
liquid form to
an atmospheric
gas
Condensation
Heat from the sun changes
water into water vapor
 Water vapor produces
droplets of water
that form clouds
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Transpiration
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The process by
which water
enters the
atmosphere by
evaporating
from leaves
Precipitation
Results when the water
droplets are large enough
and the water returns to
Earth’s surface
 The form may consist of
rain, snow, sleet, or hail
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Rain or snow falls from
clouds
Forms of Precipitation
Condensation
The movement through plants
The Clouds form
Transpiration
Precipitation
The rain falls
Evaporation
The vapor rises
Water Cycle Song
(to the tune of “She’ll Be Coming Around the Mountain”)
Water travels in a cycle, yes it does.
Use pointer finger to draw large circle in air.
Water travels in a cycle, yes it does.
Repeat above motion.
It goes up as evaporation,
Raise arms at side with palms up.
Forms clouds as condensation,
Brings hands together above head, forming large cloud shape with arms.
Then falls down as precipitation, yes it does.
Slowly lower arms at side with palms down, fingers moving.
The Carbon Cycle
Carbon Cycle
Importance of Carbon
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Found in all living
organisms
Found in the oceans,
air, and certain types
of rocks
Less than 1 %
circulates within the
biosphere
Four Process of the Carbon Cycle
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Photosynthesis and Cellular Respiration;
decomposition of plants and animals
Release of CO2 into the atmosphere by
volcanoes
Burial of carbon rich remains of organisms,
their conversion into coal and petroleum (fossil
fuels) through the pressure of overlying earth
Human Activity: mining, burning of fossil
fuels, cutting and burning down of forests
Steps of the Carbon Cycle
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Carbon is present as carbon dioxide in the
atmosphere
Released in the air by volcanic activity,
burning of fossil fuels, and decomposition of
organic matter and cellular respiration
Plants take in CO2 and use it to produce high
energy sugars (carbohydrates) during
photosynthesis
Carbohydrates are passed along the food chain
to other organisms
Steps of the Carbon Cycle
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Carbon is found in the oceans, along with
calcium and oxygen, in calcium carbonate
(CaCO3), which is produced by many marine
organisms
Calcium carbonate can also be formed
chemically in certain marine environments; it
accumulates in marine sediments and in the
bones and shells of organisms
They eventually breakdown and the carbon
returns to the atmosphere
References
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Missouri Science Teaching and Education
Partnerships
Prentice Hall Biology by Miller and Levine
Phosphorus Cycle
Phosphorus Cycle
Importance of Phosphorus
Components of nucleic acids (DNA
and RNA); life sustaining molecules
 Components of biological
membranes
 Absorbed by plants from the soil or
water and bind the phosphate into
organic compounds
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Phosphorus Facts
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Not common in the biosphere
Remains mostly on land in rock and soil
minerals, and in ocean sediments
Exists in the form of inorganic
phosphates
Released by the breakdown of rocks and
sediments
Some is washed into rivers and streams,
where it dissolves
Eventually ends up in oceans where
it is used by marine organisms
 Some phosphates stay on land and
cycle between organisms and the soil
 Organic phosphates move through
the food web, from producers to
consumers, and to the rest of the
ecosystem
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The Nitrogen
Cycle
Importance of Nitrogen
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All organisms need nitrogen to make amino acids, the
building blocks of proteins
Several different forms of nitrogen occur naturally in
the atmosphere
Nitrogen gas (N2) makes up about 78% of the Earth’s
atmosphere
Nitrogen-containing substances are found in wastes
produced by many organisms as well as dead or
decaying ones; examples are ammonia (NH3), nitrate
ions (NO3), and nitrite ions (NO2)
Importance of Nitrogen
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Nitrogen also exists in different forms in the
oceans and other large bodies of water
Human activity adds nitrogen to the biosphere
in the form of nitrate (a major component of
plant fertilizers)
Steps of the Nitrogen Cycle
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Only certain types of bacteria can use the form
of nitrogen gas
Bacteria that live in the soil, on the roots of
plants called legumes, can convert nitrogen gas
into ammonia (NH3): process is called
nitrogen fixation
Other bacteria convert ammonia into nitrates
and nitrites
Steps of the Nitrogen Cycle
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Once nitrates and nitrites are available, producers use
them to make their own proteins
Upon death, decomposers return the nitrogen back to
the soil as ammonia
The ammonia is taken back up by the producers
Other bacteria convert the nitrates back into nitrogen
gas: process is called denitrification
Denitrification releases nitrogen back into the
atmosphere