Energy and Matter Exchange in the Biosphere
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Transcript Energy and Matter Exchange in the Biosphere
Unit A
Systems
Objects or groups of objects that has a
relationship to something else
Open
Energy and matter cross the systems boundaries
humans, trees
Closed
Allows energy but not matter to cross boundary
Earth, Biosphere
Isolated
Allows neither energy or matter to flow across
boundary
Universe
BIOSPHERE
Radiant energy from sun interacts with
a thin layer of air, land and water on or
near the earth’s surface
All life on earth exists here
Living (biotic) and non living (abiotic)
components
Closed system
No real
boundaries,
everything
on Earth is
connected.
Do not see
countless
interactions
or the
impacts of
human
activity
Biosphere
3 zones
1.Lithosphere (land)
2.Hydrosphere (water)
3.Atmosphere (air)
continuously interact and these interactions change
daily
Biosphere
Part A: Make a chart that compares and
contrasts the three components of the
biosphere
Part B: Briefly explain how each part of the
biosphere supports life
Levels of Biosphere
Biosphere
Made up of
Ecosystems
Made up of all the abiotic
and biotic elements of one
specific area
Made up of
Communities
All biotic elements in a
specific ecosystem
Made up of
Populations
Groups of similar species
in a specific community
Made up of
Organisms
A single being within a
specific population
Matter Cycling in the Biosphere
organisms depends on matter already
available on earth (closed system)
It is possible that a carbon atom that helped make up a T
Rex 70 million years ago can be somewhere in your body
New matter is not introduced so nutrients
are cycled and recycled between the
environment and organisms
These cycles are called the BIOGEOCHEMICAL
CYCLES
Matter
Matter is mostly made up of the
following elements and there is a
specific cycle for each:
Carbon
Hydrogen
Oxygen
Nitrogen
Carbohydrates (energy for cells)
Lipids (storage in cells)
Proteins (structure in cells)
Nucleic Acids (genetic material in cells)
These four elements make up all basic
compounds used by living organisms
Biogeochemical Cycles
Cycling of matter through biotic and
abiotic parts of ecosystems allows
organisms to obtain essential nutrients
O, C, N, travel easily in both water & air
P does NOT travel in air but in soil and
water
Similar and interrelated
Disruptions in one can affect another
Nutrient Reservoirs
At each step in every cycle, substances
are temporarily stored in nutrient
reservoirs (organisms, soil, air, water)or
move from reservoir to reservoir
E.g. Carbon cycles from producer to consumer to
decomposers and back to atmosphere rapidly
Fossil fuels is stored carbon that is unavailable to
organisms for millions of years
The Cycling of Matter in the
Biosphere
Hydrological Cycle
Water
absorbs and release thermal energy and moderates
temperature fluctuations
Medium in which metabolic reactions take place
Is an excellent solvent
Makes up over 60% of the cell’s mass
Product and reactant of photosynthesis and cellular
respiration
Abiotic (air, water, land) and biotic organisms
Carbon/Oxygen Cycle
Carbon
Key element for living things
Cellular respiration/photosynthesis
Biotic and abiotic (air, land, water)
Rapid Cycling
Plants animals and decomposers play important role
Forest fires
Slow Cycling
3 main reservoirs of carbon in the atmosphere,
oceans, earth’s crust
Weathering
Carbon Cycle
Phosphorus Cycle
Phosphates
Short Term Cycle
Long Term Cycle
Key elements in making ATP and calcium in bones
Animals obtain phosphorus by consuming foods
such as milk, grain and meat
Producers such as plants and algae can only use it
in forms of phosphates which dissolve in water
NOT IN AIR
living organisms
Rocks in Earth’s crust
Phosphorus Cycle
Nitrogen Cycle
Nitrogen
Nitrogen Fixation
Ammonification
Denitrification
Makes up 78.1% of atmosphere
Essential part of proteins and DNA
Abiotic (Air, water, land) and biotic
Process to convert atmospheric nitrogen into useable
ammonium by bacteria or lightning
Process of converting ammonium into nitrite then
useable nitrate by bacteria so plant can use it
Process of converting nitrite and nitrate back into
nitrogen gas
Human Impact on Cycles
Carbon-deforestation, burning fossil fuels
add carbon to reservoir
Nitrogen and Phosphorus- Fertilizer add
phosphates and nitrates to the soil
Water-burning fossil fuels adds sulfuric
acid and nitric acid to the water cycle
(acid rain)
ENERGY FLOWS AND
MATTER CYCLES
The need for energy
All organisms need energy to stay alive
Use energy to grow, maintain body
processes, reproduce and some to move
Energy obtained from carbs and other
energy rich organic molecules
The fate of energy
Energy does not and cannot cycle as
matter does it follows a one way path
through the biosphere
1st law of thermodynamics
Energy cannot be created or destroyed, it can only be
converted from one form to another or transferred
from one object to another
2nd law of thermodynamics
No process of energy conversion is 100% efficient,
with each conversion there is less energy available to
do useful work
Therefore a constant supply of energy is
necessary to sustain life
Energy Flow in the Biosphere
Energy that enters ecosystem is passed
from organism to organism and is used up
or exits the system via heat
Energy drives the biogeochemical cycles
Source of earth’s energy is the sun
3 outcomes for radiant energy from the
sun
Radiant Energy from Sun
1% generates
wind
30% reflected by clouds or
surface of earth
>0.02 % is used by plants to
create useable energy
40% heats atmosphere and
earth’s surface
25% heats and evaporates water
30% is reflected back into space
ALBEDO EFFECT
Describes the amount of reflected energy
Greater the ability of area to reflect sun the
higher albedo therefore the lower the energy
absorption (light coloured, thick cloud cover,
dusty or “bald” -80%)
Lower the ability of area to reflect sun the
lower the albedo therefore the higher the
energy absorption (forest canopies and water 25%)
Average is 30 %
19% absorbed by atmosphere
Gases such as H2O vapor & CO2 in
atmosphere
Will heat the atmosphere or radiate back
into space
51% reaches surface of Earth
Absorbed by land and ocean, warms
surface
Heat radiates upward and back into space
Of the energy that reaches ground only
small fraction reaches organisms for
photosynthesis
Amount varies depending on type of organisms and
intensity of light
Fraction of light that reaches is small but about 150
billion tonnes to 200 billion tonnes of organic
(carbon) matter is produced each year and this is
the matter that supports most life on earth.
0.023% of suns energy is used by living organisms
PHOTOSYNTHESIS AND CELLULAR RESPIRATION
Two chemical processes that occur in
nature to help animals and plants turn
solar energy into useable energy
Plants use PHOTOSYNTHESIS to convert
energy
6CO2 + 6H2O + energy --> 6O2 + C6H12O6
Animals use CELLULAR RESPIRATION
to release energy
6O2 + C6H12O6 --> 6H2O + 6CO2 + energy
Complementary processes
Balance of those O2 and CO2 in the
environment
0.023% of suns energy is used by living organisms
Tracing the path energy takes from the sun to
organisms living on earth
FOOD WEBS/CHAINS visually show us
the step by step or interlocking “feeding”
relationships between organisms
Putting organisms into classifications
helps to organize the way they gain
energy from the sun
Three main levels in basic food chains/webs
1. 1st Trophic Level = Producers = Autotrophs
2. 2nd Trophic Level = Primary Consumers =
Heterotrophs
3. 3rd Trophic Level = Secondary Consumers =
Heterotrophs
Energy and the food chain
Energy is neither created nor destroyed
therefore once it enters a system it
stays and is either used up or lost as
heat into the system
As you move up the trophic levels the
amount of energy available goes down
Only 10% of energy from each level is
passed on
The number of organisms at each level
is directly controlled by the amount of
energy available to each level
ECOLOGICAL PYRAMIDS
(pg 28-32)
Visuals that help represent the energy
flow in a system
Three types of pyramids
1. Pyramid of Biomass
A measure of total dry mass of all living things in the
ecosystem
2. Pyramid of Energy
A measure of energy at each level
3. Pyramid of Numbers
A count of the number or organisms at each level
Human impact on Energy
Hunting and fishing
Monocultures
Flow of Matter and Transfer of Energy
are linked
Six cycles involve biotic and abiotic
environment
When living organisms take on nutrients
those nutrients become part of the biotic
environment
Transfer of energy from organism to
organism affect biogeochemical cycles
Balance of Matter and Energy
Earth is similar to organisms must
maintain conditions within certain limits to
ensure a state of balance (Dynamic
EQUILIBRIUM)
Gaia hypothesis-James Lovelock-
Biosphere regulates itself, needs constant input of
energy and cycling of nutrients
Ecosystem Productivity
Rate at which an ecosystem’s producers
capture and store energy within organic
compounds over a certain length of time
Rate of productivity depends on a number
of variables
Biotic factors
Number of organisms at each level especially
producers and decomposers
Abiotic factors
Temperature, amount of light and heat, rainfall,
nutrient availability
Ecosystem Productivity
This is measured in energy/area/year
(J/m2/a)
We look at how much BIOMASS is created
by the organisms
Look at the diagram!
Replicating Earth’s Biosphere
Scientist have tried to replicate the self
regulating conditions of the biosphere in
artificial environments
Biosphere 2
Large scale biosphere experiment
constructed closed systems
Several months until the oxygen levels
dropped and carbon dioxide levels rose
Proved that energy and matter exchange
is extremely complex
Research facility showed that delicate
balance
http://www.b2science.org/who/fact
NASA: Advanced Life Support (ALS)
Research plants grown in space for
oxygen and food
Conversion of waste into usable energy
Self sustaining colonies for humans
Devon Island (Canada) hypothetical
colony on Mars
http://www.nasa.gov/centers/ames/research/technology-onepagers/advanced-life-support.html