Unit 4: Ecosystems

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Unit 4 Ecosystems
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3.1.1 Define Ecosystem

• Ecosystem the network of relationships
  (interactions) among plants, animals (living) and
  the non-living parts in an environment.

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3.2.1 Producers
Other examples Grasses Trees shrubs Water
lilies Flowers Vegetables Fruits

• Producer a plant which can synthesize
  carbohydrates using carbon dioxide and the suns
  energy.
• Produce their own food AND food for the rest of
  the ecosystem

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3.2.1 Consumers

• Consumers All those organisms that have to eat
  (consume) plants or animals to obtain their food.

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Types of consumers

• Primary Consumers Animals that eat producers.
  Also called 1st. order consumers or herbivores.
  (Ex. Rabbit, squirrels, grouse, insects)
• Secondary Consumers Animals that eat primary
  consumers. Also called 2nd. order consumers or
  carnivores. (fox, owl, mink )
• Tertiary Consumers Animals that eat secondary
  consumers. Also called 3rd. order consumers or
  carnivores. (Wolf, coyote, hawk)
• Omnivores Animals that eat both producers
  (plants) and consumers (animals).

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3.2.1 Decomposers
Examples Worms Bacteria Fungi Protozoa

• Decomposers Simple organisms that obtain their
  food from dead/decaying organisms and wastes.

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Identify

• Producers
• Herbivores
• Carnivores
• Omnivores
• Whats missing?
• Decomposers!

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3.2.3 Food chain

• Food chain linear sequence representing the
  flow of nutrition from the simplest plant to the
  top carnivore.
• Ie. What eats what??

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3.2.4 Food web

• Food web a series of interconnecting food
  chains in an ecosystem.
• Shows all possible flows of nutrition.
• Much more complicated!!

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Food Chain vs Food Web
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Identify examples of producers consumersSee
Handout
Producers
Primary Consumers / herbivores
Secondary Consumers / Carnivores
Tertiary Consumers / Carnivores
Decomposers
Shrubs, grass, trees
Grasshopper, rabbit, deer
Mountain lion, snake, shrew, insect-eating bird,
hawk
Hawk, snake, mountain lion
Bacteria, fungi
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Give an example of a food chain from figure to
the right.
Tree ? insect ? insect eating bird ? hawk
Producer ? Primary consumer ? 2nd order consumer ? 3rd order consumer
Note The arrows indicate the flow of energy
nutrients from one level to the next
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Sample Food Chain
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Draw an example of a food web containing humans.

• Mosquito
• Hawk
• Cow
• Grass
• Man
• Worms
• Phytoplankton
• Fish

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Draw an example of a food web containing humans.
Hawk
Mosquito
Cow
fish
Man
Phytoplankton
Grass
Worms
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• Using a diagram, describe the relationship
  between latitude and the sequence of ecosystems.
• Using a diagram, describe the relationship
  between elevation and the sequence of ecosystems.
  (a)