Download Ecology Unit

Ecology Notes
102 Jacobs/Ebener
Ecology
 The study of
interactions
between
organisms and
their environment
Select one thing
in the picture and
remove it. What
would change?
Compare biotic and abiotic
factors
 Biotic factors: all organisms inhabiting the
environment, adapted to its particular part of
the world
Abiotic factors: nonliving parts of the
environment, can determine which species
survive
Biotic
Abiotic
Carefully observe the picture
below and list the abiotic factors
and biotic factors you see
Compare: niche & habitat
 Niche:
the unique role an organism
plays in a community, its “job” ,
unique to individual
Habitat: place where an organism
lives
Three
species of
Warblers
and their
niches
Cape May Warbler
Feeds at the tips of branches
near the top of the tree
Bay-Breasted Warbler
Feeds in the middle
part of the tree
Yellow-Rumped Warbler
Feeds in the lower part of the tree and
at the bases of the middle branches
Compare the types of feeding
relationships
oAutotrophs (producers):
self-feeders; produce own
food; example: plants
oHeterotrophs (consumers):
depend on others for food
herbivore
oHerbivore: eat only plants
oCarnivore: eat only meat
oOmnivore: eat both plants
and meat
What are you?
omnivore
carnivore
oDecomposers: break
down and absorbs
nutrients from dead
organisms (Ex: fungi and
bacteria)
oDetritivores: feed on
dead material called
detritus (AKA scavengers)
Ecology Notes
Compare Food chains, food
webs and energy pyramids
o Food Chains: model showing
movement of energy through
ecosystem using arrows to show
“what eats what”
oTrophic levels:
oPrimary consumer: eat plants
oSecondary: eats primary
oTertiary (3rd): eats secondary
Label the parts of the food chain
on your notes!
oFood web: more
complicated than
chains, shows more
than one food
source for each
organism
o Energy pyramids:
show decreasing
amounts of energy,
biomass, and number
of individuals as you
move up the pyramid
Describe limiting factors and
natural selection
oLimiting factor: factor that restricts life, reproduction, or
distribution of organisms; Ex: food, temperature, water, etc.
oNatural selection : survival of the fittest; those species that are
better able to survive in their environment will pass on their
genes to offspring which in turn will be better able to survive
oAfter long periods of time, may lead to changes in organism
SUCCESSION AND
HUMAN IMPACT
Identify the types of resources
• Natural resources: part
of natural environment,
Ex: soil, water, crops,
oil, gas, wildlife
• Renewable resources:
replaced or recycled by
natural processes
(biodegradable) Ex:
plants and animals
• Nonrenewable
resources: available in
limited amounts, Ex:
fossil fuels
Environmental Changes
• Pollution: air, water, noise
• Global Warming: Earth’s
atmosphere heating up
due to trapped gases
(fossil fuels)
– Ex: Arctic, where rising
temperatures and
melting ice are
dramatically changing
the region’s unique
landscapes and wildlife
• Acid Rain:
transformation of
sulphur dioxide (SO2)
secondary pollutants
such as sulphuric acid
• Ozone Hole: Ozone
shields us from
damaging UV sunlight.
Ozone is affected by
Chlorofluorocarbons
(CFC)
• Greenhouse Effect:
Earth's atmosphere
contains trace gases,
some of which absorb
heat.
• water vapor, carbon
dioxide, methane,
ozone, and nitrous
oxide = "greenhouse
gases."
• Extinction:
a species no longer
exists
Describe factors that
affect population size
 Predation: predators limit number
of prey; pick out old, sick, young
Competition: compete for
resources; water, food, living space,
mates
Parasitism/disease
Environmental changes: pollution,
thermal warming, unfit water all
affect population size
May cause species to become
threatened(rapid decline) or
endangered (extinction possible)
Describe population growth
 Exponential
growth: occurs when
number of
individuals increases
rapidly; produces Jshaped curve on
graph
Logistical (linear)
growth: S-shaped
curve; shows steady
growth; slows after
populations reach
carrying capacity
Describe carrying
capacity
 Carrying capacity:
the number of
individuals that an
environment can
support
# of yeast
cells
Limits the
population size
Affected by
temperature, food
supply,
reproduction,
hunting, etc.
Time in
hours
Describe
succession
 Succession: changes that take
place in a community.
Primary: occurs where no soil
existed; creates new colonies;
pioneer species move in; continues
to grow until limiting factors
become too great
Secondary: disturbance of some
kind changes existing community;
“old” species die and new species
move in; associated with natural
disasters
SYMBIOSIS
Symbiosis: a relationship between
two organisms
oCommensalism: one species
benefits and the other is not
affected (ramoras that live on
sharks)
oMutualism: both species
benefit (tickbirds eat
parasites off rhinos)
oParasitism: one benefits
and the other is harmed
(heartworms infecting a
dog’s heart)
Select 2 of
these examples
and explain
what type of
symbiosis they
exhibit.
2
1
4
3
5
6
7
CYCLES
IN 182-183
Biogeochemical Cycles
Energy flows in ONE direction
Matter is RECYCLED within an ecosystem and
between ecosystems
Law of Conservation - Matter cannot be created
or destroyed, it only changes forms
Biogeochemical cycle - matter is passed from
one organism to another and from one part of
the biosphere to another
Nutrient Cycles
• Unlike the one way flow of energy
through a biosphere, matter is recycled
within and between ecosystems.
• All of the chemical substances required
to live
• Nutrients are recycled through the
biogeochemical cycles which include
- Water cycle – pg 46 in textbook
– Carbon cycle – pg 47 in textbook
– Nitrogen cycle – pg 48 in textbook
– Phosphorus cycle – pg 49 in textbook
WATER CYCLE
Ground water, transpiration (from plants),
evaporation (from bodies of water), precipitation
(from clouds)
CARBON CYCLE
• Biological Processes: Photosynthesis,
Respiration, Decomposition of plants and
animals produce and use CO2
• Geochemical: release of CO2 gas by
volcanoes
• Mixed BioGeoChem
• Fossil fuels: Burial of carbon rich remains
and their conversion to coal and petroleum
• Human activity (mining, burning, fossil
fuels, cutting/ burning forests)
•
•
NITROGEN CYCLE
All organisms need nitrogen for amino acids;
nitrogen (N2) makes up 78% of the atmosphere
N2 is not usable
by plants - it
must be “fixed”
by bacteria.
Nitrogen fixation
- converting
nitrogen gas into
usable form of
nitrogen
(ammonium
nitrates)
When organisms die, nitrogen returns to the
soil as ammonia. Other bacteria convert
nitrogen back to nitrogen gas (denitrification)
that is released into the atmosphere.
Phosphorus Cycle
• Phosphorus is an important part of
DNA and RNA but uncommon in
biosphere (remains mostly in rock,
soil, ocean sediments)
• Plants absorb Phosphorus from soil
and H2O and bind phosphate into
organic compounds (nucleic acids)
which move through the food web
•