Download Biogeochemical Cycles Note Slides File

Biogeochemical Cycles
Nutrient cycling at its finest!
Four Criteria for Sustainability
Sustainable
Ecosystems
Need:
Reliance on
Solar Energy
High
Biodiversity
Population
Control
Nutrient
Cycling
This note set
aligns with this
concept.
What is a Biogeochemical Cycle?
• Bio - = life / living
• Geo - = Earth
• Chemical = chemical
• These are cycles in which elements or
chemicals move through biotic (living) and
abiotic (nonliving) parts of an ecosystem
Examples of Biogeochemical Cycles
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•
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•
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Carbon cycle
Nitrogen cycle
Phosphorus cycle
Oxygen cycle
Water cycle
Sulfur cycle
Rock cycle
Mercury cycle
What Are Reservoirs/Sinks?
• A reservoir/sink is a place where the chemical
of a cycle may be stored.
• There are 3 general places that chemicals in
biogeochemical cycles are stored:
– Atmosphere – the air
– Hydrosphere – the water
– Lithosphere – the land
Carbon Cycle Processes
• Label the processes on your carbon cycle
diagram. The 6 processes are:
– Photosynthesis
– Decomposition
– Cellular Respiration
– Combustion
– Sedimentation
– Diffusion
#1 = DIFFUSION
#2 = SEDIMENTATION
#3 = DECOMPOSITION or
CELLULAR RESPIRATION
#4 = PHOTOSYNTHESIS
#5 = CELLULAR RESPIRATION or
DECOMPOSITION
#6 = COMBUSTION
Prompt
• Make the definitions in this form:
• When carbon in the form of ____ and found in
_____ is converted into the form of ____ and
found in ____.
Carbon Cycle Processes
• Photosynthesis = movement of CO2 from air into food/sugar
found in biomass of autotrophs
• Decomposition = release of carbon gases into atmosphere
by decay of biomass by decomposers (like bacteria)
• Cellular Respiration = release of CO2 into atmosphere from
breakdown of food/sugar
• Combustion = burning of organic biomass to release carbon
gases (mainly CO2) into atmosphere
• Sedimentation = burial and reaction of carbon based
materials with other elements to create sedimentary rock
• Diffusion = dissolving of carbon from atmosphere into
water and vice versa
Forms That Carbon Come In
• CO2 = Carbon dioxide (gas)
• CO32- = Carbonate (ion) – shells of marine
organisms
• HCO3- = Bicarbonate (ion) – shells of marine
organisms
• Carbon in Biomass
• Sediments/Rock
• Fossil Fuels
Terrestrial Carbon Reservoirs/Sinks
• Carbon can be stored in:
– Plant Biomass
– Sedimentary Rocks (Limestone!)
– Fossil Fuels
– Soil Organic Matter
– Wetlands
#1 = DIFFUSION
#2 = SEDIMENTATION
#3 = DECOMPOSITION or
CELLULAR RESPIRATION
#4 = PHOTOSYNTHESIS
#5 = CELLULAR RESPIRATION or
DECOMPOSITION
#6 = COMBUSTION
Aquatic Carbon Reservoirs/Sinks
• Carbon can be stored in:
– Aquatic Producer Biomass
– Coral
– Marine Organisms’ Shells/Skeletons
– Water
– Sedimentary Rocks (Limestone!)
Organize the Nitrogen Cycle
• Place a form of nitrogen into each
box/rectangle in the diagram. Use the
information given about each form to select
where each form could go.
• Use each form once, except for N2, which is
used twice!
N2
N2
Organically bound Nitrogen
NO3
NO2
NH4
Wastes with Organic
Nitrogen
N2O
Forms of Nitrogen (Full Names)
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•
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NH4+ – Ammonium
NO3- – Nitrate
N2 – Nitrogen gas
NO2- – Nitrite
N2O – Nitrous Oxide
Keep Organizing the Nitrogen Cycle!
• There are 5 nitrogen cycle processes. Label
each one on your diagram from the definitions
that are given to you.
• Then jot down the definitions for your
records!
N2
N2
Organically bound Nitrogen
NO3
NO2
NH4
Wastes with Organic
Nitrogen
N2O
Nitrogen Cycle Processes
• AMMONIFICATION – conversion of nitrogen from
waste materials into ammonium
• ASSIMILATION – uptake of usable nitrogen forms
into nitrogen-containing molecules in organisms
(protein, DNA)
• DENITRIFICATION – conversion of nitrate into
gaseous forms of nitrogen
• NITRIFICATION – conversion of usable
ammonium into nitrite and then to usable nitrate
• NITROGEN FIXATION – conversion on inert
nitrogen gas into usable ammonium
N2
N2
N2O
NITROGEN
FIXATION
Organically bound Nitrogen
ASSIMILATION
NO3
NO2
NH4
DENITRIFICATION
Wastes with Organic
Nitrogen
AMMONIFICATION
Facts on Nitrogen Cycle
• All chemical transformations in the nitrogen
cycle are performed by bacteria.
• Legumes (type of plant) are well known to
house nitrogen fixing bacteria.
– If farmers plant legumes, they will also have
bacteria in the soil that perform nitrogen fixation.
– This helps reduce fertilizer use!
• Farmers who use manure for fertilizer are
trying to promote ammonification to get more
usable ammonium in the soil.
Human Alteration of Nitrogen Cycle
• The Haber Process
– This is a method developed to make
inorganic (synthetic) fertilizer.
– In the process, you put N2 through a
series of high energy chemical reactions
to make NH3 or NH4.
– Positives:
– We make more fertilizer that is easy to use.
– We are finally using a readily found form of
nitrogen (N2)
– Negatives:
– Fossil fuels are used to create the high
energy chemical conditions needed for the
reaction.
– Humans now make and use much more
fertilizer than before, and fertilizer is a
pollutant in waterways.
Phosphorus Cycle
• Forms of Phosphorus
– Phosphate ion (PO43-)
• Found in rock, water
– Organically bound phosphorus – in living things
• What is phosphorus used for?
– Building block of DNA, RNA, ATP, cell membranes
Phosphorus Cycle
• Reservoirs/Sinks of Phosphorus
– Organisms
– Lithosphere
– Hydrosphere
• How Can Humans Impact This Cycle?
– Phosphate can be mined from rocks to use in
fertilizers.
– This means more phosphates get into water
quicker, when fertilizers are used.