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•
•
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Ecology (Section 3-1)
Energy flow (Section 3-2)
Cycles of Matter (Section 3-3)
Ecosystems (Section 4-1)
Biomes (Section 4-2)
Aquatic Ecosystems (Section 4-3)
How populations grow (Section 5-1)
Limits to population growth (Section 5-2)
Human population growth (Section 5-3)
K. Malone 2006
Ecology, Ch 3-5
• The second sentence at the bottom of the
first page. “When a nutrient such as
water, carbon……”
• Boxes 12-14
• Under 16
• Box 20
K. Malone 2006
Cross out
Section 3-1
• Ecology = scientific study of Box 1
interactions between organisms, and
between organisms and their environment
• Eco comes from the Greek word “oikos” which
means “house,” so ecology is the study of YOUR
house-Earth!
• Nature has many “houses”
– Biosphere = all parts of our earth where life exists
• No life is an island unto itself
• Life depends on interactions between living and
non-living parts of the biosphere
• All life is inter-dependent
– Birds eat worms that live on leaves of trees, trees depend on
soil, sunlight and water
– Humans eat plants and animals, breathe air, and drink water,
K. Malone 2006
Ecology
Bio = life
Sphere = circle
Biosphere = The circle of Life!
6 Levels of Organization
1. Biome
Group of ecosystems with the same climate and similar dominant communities
(desert, tundra, taiga, temperate forest, tropical rainforest, artic)
2. Ecosystem
Collection of all organisms that live in a particular place, together with
the non-living parts of their environment
3. Communities
Assemblies of different populations living in a defined area
4. Populations
5. Species
Groups of individuals belonging to the same species and
living in the same area
Group of organisms so similar to one another they can
breed and produce fertile offspring
6. Individual
One member of a species
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Box 2
6 Levels of Organization
?
Ecosystem
Community
Population
?
Species
Individual
?
?
?
?
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Biome
Producers produce
Sectionfood
3-2
• Everything needs energy
• What is the ultimate source of energy?
• The Sun!
Auto = self
Box 3
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Energy Flow
Troph = nourishment
• Energy flows through an ecosystemBox 3
• Producers = obtain energy directly from
the sun or capture energy from chemicals
– Autotrophs = plants, some algae, and certain
bacteria can capture the sun’s energy or use
chemicals to produce their own food
– Essential to the flow of energy through an
ecosystem
– Autotrophs are producers
I’m a
producer!
Box 3
I hate to break it to you, but you are not an autotroph.
Energy From the Sun!!
• Photosynthesis = uses sunlight
energy to power chemical reactions
that convert CO2 and H2O into O2 and
energy-rich carbohydrates (sugars and starches)
– Plants, algae, photosynthetic bacteria
• Without photosynthesis, you wouldn’t have
air to breathe or food to eat- you would DIE!
6CO2 + 6H2O
6O2 + C6H12O6
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Box 3
Consumers
Box 4
• Heterotrophs = organisms that rely on
other organisms for their energy and food
supply
• You consume animals and plants to obtain
energy, you are a CONSUMER
• Types of heterotrophs: cow, sheep, caterpillar
–
–
–
–
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• Ok, you’re not an autotroph,
so what are you?
Herbivore – eats only plantssnakes, dogs, owls
Carnivore- eats only animals
humans, bears, crows
mites,
Omnivore- eats plants and animals
earthworms,
snails, crabs
Detritivore – eats plant and animal remains, dead things
bacteria, fungi
Food Chains
• Energy flows in only ONE direction, from
the sun to autotrophs then heterotrophs
• Who eats who forms a network of feeding
relationships called a Food Chain
• Food Chain = series of steps in which organisms Box 5
transfer energy by eating or being eaten
• ALL food chains begin with producers, no
exceptions!!!!
= Food Chain
Producers
1st level consumers
2nd level consumers
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Box 5
• Life isn’t simple, most ecosystems consist
of a series of food chains called Food Webs
• Food Web = links together all the Food
Box 6
Chains in an ecosystem
= Food Web
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Food Webs
Food Web
Each step in a food
chain or web is called
a Trophic Level.
Each trophic level
depends on the level
above and below it.
Top level
carnivores
K. Malone 2006
marsh
hawk
Box 7
clapper rail
(omnivore)
heron
shrew
1st level
consumers
plankton
eating fish
ribbed mussel
herbivores
harvest
mouse
(omnivore)
sandhopper
zooplankton
pickle weed
marsh grass
algae
detritus
decomposers
producers
Ecological Pyramids
K. Malone 2006
• Amounts of energy and matter in an ecosystem
can be represented by an ecological pyramid
• 10% Rule: only about 10% of the energy available
within one trophic level is transferred to organisms at
the
next level
Where did the 99.9% of the energy go?
Box 8
Energy Pyramid
3rd order consumers = 0.1%
0.1%
1%
10%
100%
Box 16
2nd order consumers = 1%
1st order consumers = 10%
Producers = 100%
Biomass Pyramid
• Biomass = total amount of living
tissue within a given trophic level
– Usually expressed in grams of organic matter/unit area
– Biomass pyramid represents total amount of potential food
available for each trophic level in an ecosystem
100 grams of human tissue
500 grams of chicken
1500 grams of grain
Typically, the greatest biomass is at
the base of the pyramid.
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Box 8
• Each trophic level harvests only about one
tenth of energy from the level below it
Shows the relative number of individual organisms at each trophic level.
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Pyramid of Numbers
Less top predators like the eagle
More 1st and 2nd order consumers, the prey
Producers, like plants, are the most abundant
Box 8
• Unlike the 1-way flow of energy in an
ecosystem, matter recycles in and
between ecosystems
Box 9
• Biogeochemical Cycles = elements,
chemical compounds, and other forms of matter
are passed from 1 organism to another and to
other parts of the biosphere
– Water cycle
– Nutrient cycles
• Nitrogen cycle
• Phosphorous cycle
• Carbon cycle
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Cycles of Matter
Section 3-3
Box 9
• All living things depend on H2O
to survive
• It moves between the ocean,
atmosphere and land, constantly recycling
• Evaporation = process where H2O changes
from liquid to atmospheric gas
– Evaporation is from oceans or other
bodies of H2O
• Transpiration = H2O entering atmosphere
by evaporating from leaves of plants
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Water Cycle
K. Malone 2006
Water Cycle
condensation
precipitation
evaporation
transpiration
run off
seepage
root
uptake
• Nutrients = all the chemical substances
an organism needs to sustain life Box 9
– Producers obtain nutrients from their environment
– Consumers obtain nutrients by eating other organisms
• Every living organism needs nutrients to build
tissues and carry out essential life functions
• Like H2O, nutrients are passed between organisms
and the environment through biogeochemical
processes
• The 3 Nutrient Cycles are:
– Carbon cycle
– Phosphorous cycle
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Nutrient Cycles
Carbon Cycle
• You are full of CHON, but Carbon
is the main ingredient of living tissue
• 4 main types of processes move carbon
through its cycle:
1. Biological processes = photosynthesis, respiration,
decomposition
2. Geochemical processes = erosion and volcanic activity
release CO2 into the air and oceans
3. Mixed biogeochemical processes = burial and
decomposition of dead organisms, and their turning into
fossil fuels (coal, oil, natural gas)
4. Human activities = mining, cutting and burning forests,
burning fossil fuels,= release CO2 into air
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Box 9
Carbon Cycle
In the atmosphere –CO2 gas
In the oceans- dissolved CO2
On land –in organisms, rocks and soil
Underground –coal, oil and calcium
carbonate rock
Box 9
CO2 in
atmosphere
CO2 in ocean
K. Malone 2006
Carbon is found in several large
reservoirs in the biosphere:
Nitrogen Cycle
• All organisms require nitrogen to make
amino acids, the building blocks of proteins
• Different forms of naturally occurring Nitrogen:
• Nitrogen gas (N2)- makes up 78% of Earth’s atmosphere
• Nitrogen containing substances – such as ammonia (NH3) and
nitrate ions (NO2-)
• Some bacteria “fix” nitrogen from the air,
converting nitrogen gas into ammonia = Nitrogen
fixation
• Live on roots of plants and in soil
• Consumers eat the plants and use the nitrogen to make
proteins
• Denitrification = when soil bacteria convert nitrates
into nitrogen gas, which is released into the air
K. Malone 2006
Box 9
• Phosphorous (P) is essential to living
organisms because it forms part of
important life-sustaining molecules
like DNA and RNA
• Despite its importance, P is not very
common in the biosphere
– P exists in the form of inorganic phosphate found in
rocks and soil
– P washes into rivers, streams and lakes where it
dissolves and eventually ends up in the ocean
– P also remains on land where it cycles between
organisms and the soil
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Phosphorous Cycle
P = phosphorous,
not pee
Box 10
P?
In our
rivers?
Nasty!
Section 4-1
CO2, methane, H2O vapor, and a few
other atmospheric gases trap heat energy
and maintain Earth’s temperatures
• Act like windows of a greenhouse, keeping us
warm
Sunlight
• Greenhouse effect = heat retained
by a
Some heat
escapes
layer of greenhouse gases
into space
Greenhouse
gases trap
some heat
Atmosphere
Earth’s surface
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Ecosystems and
Communities
• Greenhouse effect = (technical definition)
• Biotic factors = living, biological,
factors that shape ecosystems
• Trees, mushrooms, bacteria, animals, flowers, etc.
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Parts of an Ecosystem
Section 4-2
• Abiotic factors = physical or non-living
factors that shape ecosystems
• Rocks, water, soil, air, sunlight
• Biotic + Abiotic factors determine the survival
and growth of an organism and the productivity
of the ecosystem
Biotic factors
Abiotic factors
Who Lives in an
Ecosystem
• Habitat = an organism’s address,
where it lives
• Niche = an organism’s occupation,
what it does in its habitat
– Includes:
•
•
•
•
Where it fits into the food web
Type of food it eats
How it obtains food
When and how it reproduces
K. Malone 2006
Bernie’s habitat
No one else
could do
MY job.
Bernie’s niche
• No 2 species can share the SAME habitat and the
SAME niche
• But, different species can occupy similar niches in
the same habitat
Community Interactions
K. Malone 2006
• Organisms constantly interact with
each other
– Community Interactions include:
1. Competition
2. Predation
3. Various forms of symbiosis
Box 15
1. Competition = occurs when organisms of the same or
different species attempt to use an ecological resource in the
same place, at the same time
Resource = any necessity of life (H2O, nutrients, light, food, or
space)
Competitive Exclusion Principle = no 2 species can
occupy the same niche in the same habitat at the same time
Predation and Symbiosis
Box 39
Box 15
Symbiosis (sim-by-OH-sis)= any relationship in
which 2 species live closely together
3 Main classes of Symbiotic Relationships:
•Mutualism = both species benefit from the relationship
Box 16
K. Malone 2006
2. Predation = interaction in which 1 organism
captures and feeds on another organism
Clownfish in
Sea Anemone
Ex.
Flowers and bee pollinators
Box 17
•Commensalism = 1 member benefits and the other is neither
helped or harmed (doesn’t care) Ex. Clownfish live inside poisonous
sea anemones where they hide from predators, and in return, they clean
the anemones’ tentacles and drop pieces of food for it
Box 18
•Parasitism = 1 member lives on or inside an organism and harms
it
Ex. Mistletoe is a parasitic plant, it can kill it’s host. Also,
Biomes
•
•
•
Earth is divided into 10 biomes
Biome = a complex of terrestrial
communities covering a large area,
characterized by a certain type of soil and
climate, and contains particular types of
plants and animals
Earth’s 10 Biomes are:
Tropical rain forest
Temperate forests
Tropical dry forest
Northwestern Coniferous forest
Tropical savanna
Desert
Temperate wood and shrub-land
Boreal forest
Temperate grasslands
Tundra
K. Malone 2006
Section 4-3
• 3 important characteristics of
populations:
1. Geographic distribution (where it is)
2. Density (how many live there)
3. Growth rate (how fast is pop growing)
• Population Density = # of individuals per unit area
• Population Growth is affected by 3 factors:
1. Number of births
2. Number of deaths
3. Number of individuals who enter or leave
Immigration = movement of
individuals IN to an area
Emigration = movement of
individuals OUT of an area
K. Malone 2006
Ch 5- Populations
Section 5-1
Exponential and Logistic Growth
Box 11
K. Malone 2006
• Exponential Growth = occurs when individuals in
a population reproduce at a constant rate
• Under ideal conditions with unlimited
resources, a population will grow exponentially
Box 11
• Logistic growth occurs when a population’s growth Oops! We ate
all the trash!
slows or stops
• Carrying Capacity = # of individuals the environment
Box 11
can support without undergoing deterioration
Maggots in a
Garbage Can
Carrying capacity
Time (hours)
Limits to Growth
Section 5-2
• Limiting factors = factor that causes
population growth to decrease
• Competition, predation, parasitism, drought and
other climate conditions, human disturbance
• Density-dependent factors = limiting
factors that depend on the populations
size
• Competition, predation, parasitism, disease
• Competition = when organisms compete
with each other for resources
– Too many people, too few jobs
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Bottom of 1st page- cross out 2nd sentence
Predation
Box 15
• Populations in nature are controlled by predation
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• Predator-Prey relationships = one of the
best mechanisms for population control
Relationship
Between Wolves and Moose on Royale Island (Lake 2400
Superior)
60
50
2000
40
1600
30
1200
20
800
0
400
0
1955
1960
1965
1970
1975
Moose
1980
Wolves
1985
1990
1995
populations no matter what the size
• Weather, natural disasters, seasonal cycles,
certain human activities (damming rivers, clear cutting
K. Malone 2006
Density-Independent
Factors
• Density-Independent Factors affect all
Box 11
forests)
– The Tsunami in Sri Lanka affected all populations there,
human, animal and plant
– Volcanic eruption of Mt. St. Helens affected
all populations in that area
– Mud slides in California have affected humans and
all other non-human populations
The largest world tsunamis generated by earthquakes during the last 55 years are:
1952 – Kamchatka Peninsula (Russian Far East) – 18 to 19 meters high (< 2000 fatalities),
1960 – Chile – 25 meters high (< 500 fatalities),
1964 – Alaska – 67 meters (< 100 fatalities reported),
2004 - Indian Ocean - up to 30 meters high (< 200,000 deaths) - 8 countries affected on three continents.
Human Population Growth
Underdeveloped countries
tend to have higher
population growth rates, but
they also have higher death
rates – disease, famine, etc.
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• In 2000, the world had 6.1 billion human inhabitants.
• This number could rise to more than 9 billion in the next
50 years.
• For the last 50 years, world population multiplied more
rapidly than ever before, and more rapidly than it will ever
grow in the future.
Low growth rate
Low growth rate
So, what is China’s excuse?
Explosive growth rate
Very high growth rate
Higher growth rate
Low growth rate
Industrial
Revolution
begins
Agriculture
begins
Plowing
and
irrigation
Bubonic
plague
We had a long, slow start, but improvements in medicine, sanitation, agriculture,
energy use, and technology has allowed our population to grow exponentially.
So, what’s going to happen to us if this type of population growth continues?
We will reach our carrying capacity – resources will be exhausted, disease,
famine, wars, natural disasters, or we’ll find a way to emigrate to new planets
and start all over again.
K. Malone 2006
How We Grew So Fast
Age Structures
U.S. Population
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Age-structure diagrams = (population profiles) graph the numbers of people in
different age groups in the population
Rwandan Population
More older people
(no reproducing)
Who can
reproduce
Who will
reproduce
Box 19
• Ecological Succession- As an ecosystem
changes- older inhabitants die out and
new move in causing change in the
community.
• Primary Succession- succession that
occurs where no soil is. This would
happen where volcanic eruptions have
built new islands or cover the land. The
1st species to populate an area would be
lichens. (fungus/algae that grow on rock
and help form soil)
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Succession
K. Malone 2006
Primary Succession
• Secondary Succession- occurs when a
disturbance of some kind changes a
community without removing the soil.
• Examples: wildfires burn woods, land
cleared by a plow
K. Malone 2006
Succession
Whale dies. Body colonized.
Over time the
colonies change as
succession
continues.
K. Malone 2006
Succession in a Marine
Ecosystem