Chapter 3: The Biosphere
What is ecology?
Ecology and Biomes
Ecology
• Ecology – the study of interactions among
organisms and between organisms and
environment
• Interdependence- is mutual dependence
between things.
Levels of Organization
Levels of Organization
• Biosphere – largest, portions of planet where
life exists (land, H2O, air)
– 8 km above to 11 km below
Levels of Organization
• Biome – group of ecosystems with same
climate, rainfall/freshwater, elevation, latitude
• Ecosystem – collection of all organisms in a
particular place together with the abiotic
(physical) environment.
Levels of Organization
• Community – groups of different
populations that live together in a defined
area.
Levels of Organization
• Population – groups of individuals of same
species in same area.
Levels of Organization
• Species – group of organisms so similar that
they can mate and produce fertile offspring.
Biotic and Abiotic Factors
• Biotic – living
– Plants, Animals ,Mold,
Fungi, Bacteria, Protist
• Abiotic – Nonliving
– Sunlight, soil, wind, water,
temperature
• Habitat – the area where an
organism lives; includes both
biotic and abiotic factors.
Ecological Methods
1. Observation – 1st step to
designing an experiment
2. Experiment – test
hypotheses; imitate &
manipulate
3. Modeling – make models
based on observation &
experiment
•
Helps make future predictions
3.2 Energy, Producers, and
Consumers
• One of the most important factors
to determine capacity to sustain life
•Leopard, Hyena, Lion
•Peregrine Falcon Dive
Producers (Autotrophs)
• Can trap sunlight to produce food
– Plants
– Some protist
– Some bacteria
• Photosynthesis – captures solar energy and
converts it to chemical energy
6CO2 + 6H2O
C6H12O6 + 6O2
SUN
• Chemosynthesis – Chemical energy
used to produce carbohydrates
Consumers (Heterotrophs)
• Can’t trap energy directly;
must acquire it from other
organisms
–
–
–
–
Herbivores – plants
Carnivores – animals
Omnivores – both
Detritivores – remains of
dead plants & animals
– Decomposers – break down
organic matter
3.3 Energy Flow in
Ecosystems
• Food Chains and Food Webs
Food Chains and Food Webs
SUN
Autotrophs
Heterotroph
1. Food Chain – energy trapped by producers
passed on when organisms eat and are eaten
2. Food Web – relationship more complex than a
chain
Trophic Levels and Ecological
Pyramids
• Trophic Levels – each step in a food chain/web
Ex: producers, then consumers
• Ecological Pyramids – shows relative amount of energy
at each level (10% rule)
• Biomass – total amount of living tissue within a trophic
level
3.4 Cycles of Matter
*Recycle Matter*
Carbon Cycle
• Photosynthesis – uses CO2 from atmophere
– Happens in the CHLOROPLAST
6CO2 + 6H2O
C6H12O6 + 6O2
• Respiration – returns CO2 to atmoshere
– Happens in the MITOCHONDRIA
C6H12O6 + O2
H2O + CO2
Carbon Cycle
The Carbon Cycle
1. Volcanoes, respiration, fossil fuels, and
decomposition add CO2 to atmosphere.
2. Plants take CO2 and make carbohydrates
3. Plants are eaten by animals and carbohydrates
are passed through the food chain.
4. As the animal breathes and eventually dies and
decomposes CO2 is return to atmosphere.
Water Cycle
Bill Nye - Clouds
Water Cycle
1. Water enters the atmosphere by:
•
•
Evaporation – water changes from a liquid to a
gas
Transpiration – Evaporation through leaves
2. As water rises it cools condenses into tiny
droplets that form clouds.
3. Droplets returns to Earth as precipitation.
4. Water enters the rivers, ground water, ocean
or plant roots to restart cycle.
Nitrogen Cycle
Nitrogen
Cycle
Nitrogen gas makes up 78% of atmosphere
1.
2. Nitrogen Fixation: bacteria take nitrogen gases
and turn it into ammonia, nitrite, and nitrate.
3. Plants and animals use nitrate to make amino
acids.
4. Animal dies and decomposes returning nitrates
to the soil.
5. Denitrification: other bacteria convert nitrates
into nitrogen gas.
Legumes and Nitrogen Fixing Bacteria
Algae Blooms
The Phosphorous Cycle
• Phosphate – parts of DNA/RNA
• Found in rocks that are worn down
• Washes into rivers/streams/oceans for
marine organisms
• Taken in by plants and turned into organic
compounds
Nutrient Limitation
• Primary Productivity – the rate at which
organic molecules are created by producers
• If nutrients are in short supply, they are
called LIMITING NUTRIENTS
Ex: Nitrogen is often limiting in water; if
there is suddenly an input of N (fertilizer
runoff), organisms can grow rapidly (Algal
Bloom)
Discussion questions:
1. How many stops can you make on your trip?
2. Will your journey ever end?
3. Was everyone’s journey the same? Why not?
4. What would happen if a farmer used too much
fertilizer? (In this game, that would mean that
everyone started from the fertilizer station at the
same time.)
5. Livestock farming creates a large amount of
animal waste. How would this affect the nitrogen
cycle?
Bald Eagle – Temperate Forest
Black bear – Temperate Forest
Silver Gibbon – Tropical Forest
Toucan – Tropical Forest
Pit Viper – Tropical Forest
Mountain goat – Boreal - Alpine
Snowy owl – Tundra
Caribou – Tundra
Desert Big Horn – Desert
Antelope – Desert
Gila Monster – Desert
Koala – Grassland
Lion– Grassland
Zebra - Grassland
The three basic types of population distribution within an area.
From left to right, spaced (uniform/regular), random and clumped
(aggregated
Questions for tree hole community article:
1. What is a tree hole community (what lives there,
what interactions exist)?
2. How did this scientist choose to gather data
about the tree hold community (what method did
he use to study it)?
3. How did the researcher describe the relationships
with the tree holes?
4. What three factors did this particular researcher
study within the tree holes?
5. Lastly, why can’t interactions between wolf and
deer populations be studied the same way as tree
holes?
The three basic types of ecological pyramids: energy, biomass
and numbers.
The three basic types of ecological pyramids: energy, biomass
and numbers.
Marine environments can have inverted biomass pyramids
because primary producers are phytoplankton. These tiny
photosynthetic organisms reproduce rapidly so a small mass has a
fast rate of primary production (energy available)
Why is this pyramid
of numbers inverted?
Why is this pyramid
of numbers inverted?
If a person needs 3,000 Calories per day, then 30,000 Cal beef are needed, which in
turn need 300,000 Cal of corn, which in turn means 30,000,000 Cal of sunshine.
This works out to be 1.5 acres of corn per day per person. If the person ate corn
directly then 10 people could be supported by the same 1.5 acres of corn.