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					Ecology - Unit 1
        Topics covered:
        Levels of organization
        Energy & matter flow
        Population growth
        Succession
        Biomes
        Etc…
      What is ecology?

ECOLOGY is the study of interactions
between organisms and their
environment
The Biosphere
 Where are some places we find living
 things?
   Land, Air, Water (fresh & salt)


 BIOSPHERE- portion of Earth that
 supports living things
Factors that affect living
things
 Organisms around the world vary
 depending on their location

 Living things are affected by the non-
 living and living parts of their
 environment
Abiotic Factors (Non-Living)
 ABIOTIC FACTORS- Non-living parts of an
 organisms environment

 Examples?
   Air currents
   Temperature
   Salinity
   Light
   Moisture
How do abiotic factors affect
living things?
 Determine what types of organisms can
 live in the environment

   Examples:
     Lack of rainfall in the desert determines what
     types of plants can survive
     Salinity of sea water determines what type of
     bacteria can thrive in it
Biotic Factors (Living)
 BIOTIC FACTORS- all the living
 organisms that inhabit an environment
   Examples:
     Zebra
        Do they travel in packs?
        What do they eat/what eats them?


 All living things depend on others
 directly or indirectly
Levels of Organization
        Organism


                   Population



                                Community




              Ecosystem
Organism
 An individual living thing
Population
 A group of organisms, all of one species,
 which interbreed and live in the same place
 at the same time

 Interactions:
   Share resources
   Compete
Community
 All the populations of different species
 that live in the same place at the same
 time
Community interactions
 Changes in one community may cause
 changes in another
  Example:
    Increase in lions may mean a decrease in
    zebras
    Two communities sharing the same food
    source will compete with each other
       One may have to leave and find another place to
       live and eat
Ecosystem
 Populations of plants and animals that
 interact with each other in a given area
 and with the abiotic and biotic factors of
 the area
Ecosystem interactions
 Two major types
   Terrestrial (on land)
   Aquatic (in water)

 Frequently change due to changing
 biotic and abiotic factors
   Tide pools
     Abiotic factor: moisture level changes
     Biotic factors must compensate
Organisms in Ecosystems
HABITAT-
 Where an organism lives out its life


Examples
 Under a log
 In your intestine
 In a temperate forest
 Near a deep sea vent
Within that habitat…
 NICHE-
   HOW an organism lives its life
     What it eats
     What it uses for shelter
     Where it reproduces


 Organisms cannot exist in the same
 community for long if they have the same
 niche!
     One will have to move, adapt, or become extinct
Survival Relationships
 Predator-Prey
   PREDATORS- seek out and eat other
   organisms
   PREY- animals the predators eat

   Examples:
     Hawk and mouse
     Lion and zebra
     Human and deer
Symbiosis
 SYMBIOSIS- organisms living together

 Types of symbiosis:
   Mutualism
   Commensalism
   Parasitism
Mutualism

 MUTUALISM-
  Type of symbiosis where both species
  benefit

    Examples:
       Crabs and anemones
       Ants and acacia trees
       Bees and flowers
Commensalism
 COMMENSALISM
  One species benefits, the other isn’t
  harmed or benefited
    Examples:
       Spanish Moss
       Bromeliads
Parasitism
 PARASITISM
  One organism benefits while the other is
  harmed

  Examples
    Tapeworm
    Pinworm
    Fleas
    Ticks
Feeding relationships within
      an ecosystem
It all starts with the SUN
 The sun is the ULTIMATE SOURCE
 OF ENERGY for life
Autotrophs
 “Self-feeders”
   Use the sun’s energy to make
   their own food
   Plants and algae
   Known as - PRODUCERS
Heterotrophs
 Unable to make their own food
   Obtain nutrients by eating other organisms
     Known as CONSUMERS
     May eat producers, other consumers or both
     If it consumes a producer it is called a primary
     consumer, if it eats a primary consumer it is
     called a secondary consumer… etc.
Types of Consumers
 HERBIVORE- eats
 only autotrophs (plants)


 CARNIVORE- eats
 only other heterotrophs


 OMNIVORE- eats both
 auto and heterotrophs
Types of Consumers
              SCAVENGER-
              eats only
              heterotrophs, but
              doesn’t kill it’s own
              food

              DECOMPOSER-
              break down and
              release nutrients
              from dead
              organisms
Recycled Matter

 Matter (carbon, nitrogen,
 etc…) cycles through the
 ecosystem.

 REMEMBER: Matter cannot
 be created or destroyed- it is
 converted between different
 forms.
Energy flows too!
Within matter, you have trapped
energy.

Energy is also cycled through the
ecosystem from one level to the next

Represented by a FOOD CHAIN
A food chain is broken into
levels
 Each step is a TROPHIC LEVEL
   “feeding level”

 Grass--> Grasshopper --> Frog --> Bird
     Trophic Levels
Primary producer
                           Secondary consumer

            Primary consumer




            -->            -->        -->


                                 Tertiary consumer
Energy Flow
 Energy moves up the levels
   Arrow always points to the organism
   gaining the energy (doing the eating)




Grasshopper       Frog gains   Bird gains
gains energy        energy      energy
How could we improve this
food chain?
 What are we forgetting?

 Do all creatures have only one food
 source?

    berries

    fish
Food Webs
  Not all feeding relationships can be
  defined by a straight line!

  FOOD WEBS show all the possible
  feeding relationships at each level in an
  ecosystem
    Many food chains linked together
Food webs show connections
 Show us where each organism gets its
 energy & matter (food)

 But there’s another way to show how
 energy moves within an ecosystem
Ecological Pyramid
 Show the relative
 amounts of
 energy or matter
 in a trophic level

 Three Types
   Energy
   Numbers
   Biomass
Energy Pyramid
Only part of the energy at
each level can be used
(10%)

  Respiration
  Movement
  Metabolism
  Heat
Energy Pyramid
 Only 10% of the energy available within
 one trophic level is transferred to
 organisms at the next trophic level
Biomass Pyramid
 Total amount of living tissue within a
 given trophic level
Pyramid of Numbers
 Number of individual organisms at each
 level
How do plants and animals
survive where they live?
 Develop specific adaptations to biotic
 and abiotic factors, including:
   Temperature
   Moisture Level


 Are these factors restricting in any
 way?
Limiting Factors
 What other factors might limit the types
 of organisms that can live in a
 community? (biotic or abiotic)

 LIMITING FACTORS-
   any biotic or abiotic factor that restricts the
   organisms in a community
How could you overcome
these factors?
 What types of things do organisms do to
 “beat the heat”?

 Be “flexible”

 TOLERANCE-
   ability to withstand fluctuations
      Fluctuations in…
         biotic or abiotic factors
Things are changing…
 How has the environment of the
 Huntley area changed over the years?
Succession:
Changes over Time
 What would happen if we stopped
 cutting the grass in a field? How would
 it change over time?
Succession
 SUCCESSION-
  natural changes that occur over time in an
  ecosystem
Let’s start with nothing…
 Imagine a land with nothing- no soil,
 little water, no living organisms
   Example: volcanic lava flow


 Overtime, organisms would adapt to
 grow in this environment
   PRIMARY SUCCESSION- starting a
   community where there was nothing
Pioneer Species
 First species to
 take hold on the
 barren land

   LICHENS
     Fungus + algae
June 1988 Forest Fire
Yellowstone National Park
  Fire destroys much of the
  forest
  Almost like a “barren land”


Can a forest or ecosystem
recover from this?
Yes!
 SECONDARY
 SUCCESSION-
  Changes that take
  place after one
  community is
  severely disrupted
Eventually…
 Communities become well established
   CLIMAX COMMUNITIY
BIOMES
What is a biome?
Biomes
 Biomes are geographical areas made
 of plants and animals who are very well
 adapted to their environment
Where can we find different
biomes?
What makes a biome?
 Two biggest abiotic factors:
   Temperature
   Moisture level


 What dictates these factors?
Location, Location, Location!
Take a walk…
What’s changing?
 Your LATITUDE
   Position north and
   south of the equator


 LONGITUDE?
Latitude vs. Longitude
 You can use coordinates to tell you where
 you are
   60º N, 90º W (+60, -90)?
But why do biomes change
with the latitude?
               The sun’s intensity
               changes based on
               distance

               Where is the sun’s
               energy the most
               intense?
Types of Biomes
 Terrestrial (land)

 Aquatic (water)
   Marine (Salt H20)
   Freshwater
Terrestrial
 Taiga
 Tundra
 Desert
 Tropical Rainforest
 Grassland
 Temperate deciduous forest
Tundra
 Cold temperatures
 Almost no trees
 Short growing
 seasons
   Permafrost in soil
Taiga
 Subarctic (cold)
 Coniferous (pine)
 trees
 Low precipitation
 Poor soil
Temperate Fores
 Seasonal changes
 Many broadleaf
 trees
 Larger diversity of
 life than tundra and
 taiga
Grassland
 Lots of….. Grass
 Flat
 Fertile soil
 Capable of supporting
 large amounts of
 animals
 Not a lot of trees
Desert
 Dry
   Rate of evaporation
   exceeds rate of
   precipitation
 Plants and animals
 need to be well
 adapted
   Not a lot of either
   (plants or animals)
Tropical rain forest
 Year round growing
 conditions
 Vast biodiversity
 Lots of precipitaion
Aquatic Biomes
 Determined by depth, flow, temp., and
 chemistry of water
   Mostly ABIOTIC FACTORS


 Aquatic food chains start with
 PLANKTON
Freshwater Ecosystems
 FLOWING WATER ECOSYSTEMS
  Rivers, streams, creeks, brooks
  Organisms adapted to rate of flow
Freshwater Ecosystems
STANDING
WATER
ECOSYSTEM

 Lakes, ponds
 Water circulates
 within them
 Plankton like this
 habitat
Marine Biome Zones
PHOTIC vs APHOTIC
PHOTIC zone is
shallow, and light
can penetrate
it
Great species
diversity
What organisms
might we see here?
Intertidal zones
Shoreline

Always changing-
Organisms must be
tolerant!
Estuaries
 Place where fresh
 and salt water meet

				
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