Transcript What is ecology?

What is
Ecology?
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What is Ecology??
• The study of interactions that
take place between organisms
and their environment.
• It explains how living
organisms affect each other
and the world they live in.
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Organisms and Their
Environments
Species interact with both other species and
their nonliving environment.
Interdependence is a theme in ecology—one change
can affect all species in an ecosystem.
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Habitat & Niche
• Habitat is the
place a plant or
animal lives
• Niche is an
organism’s total
way of life
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Levels of Organization
• Ecologists have organized the
interactions an organism takes part
in into different levels according to
complexity.
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Levels of
Organization
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1st Level of Organization
• Organism:
An individual
living thing that
is made of cells,
uses energy,
reproduces,
responds, grows,
and develops
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2nd Level of Organization
• Population:
A group of
organisms, all
of the same
species, which
interbreed and
live in the
same place at
the same time.
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3rd Level of Organization
• Biological
Community:
All the
populations of
different
species that
live in the same
place at the
same time.
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4th Level of Organization
• Ecosystem:
Populations of
plants and animals
that interact with
each other in a
given area with the
nonliving
components of that
area.
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Ecosystems can be terrestrial or
aquatic…
Lake
Prairie
Stream
Forest
Wetland
5th Level of Organization
• Biosphere:
The portion of
Earth that
supports life.
• Extends from
about 8km
above the
Earth’s surface
to as far as
8km below the
ocean!
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Components of an Ecosystem
Both living (biotic) and nonliving
(abiotic) factors influence organisms
and their ecosystems.
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The Nonliving Environment
• Abiotic factors- the
nonliving parts of an
organism’s environment.
• Examples include air
currents, temperature,
moisture, light, and soil.
• Abiotic factors affect an
organism’s life.
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The Living Environment
• Biotic factors- all the
living organisms that
inhabit an environment.
• All organisms depend on
others directly or
indirectly for food,
shelter, reproduction, or
protection.
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Abiotic or Biotic?
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Biotic
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Abiotic or Biotic?
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Abiotic
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Abiotic or Biotic?
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Abiotic
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Abiotic or Biotic?
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Biotic
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What level of organization?
Organism
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What level of Organization?
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Ecosystem
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What level of Organization?
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Population
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What Does it Mean to Succeed???
Ecological Succession
is the process by which
an existing ecosystem is
gradually replaced by
another ecosystem
Ecological Succession of a Pond
Community
Begins as a thriving pond community….
Ecological Succession of a Pond
Community
The pond begins to fill with organic
matter like leaves, and silt, a fine
soil…..
Ecological Succession of a Pond
Community
Over a period of time, the pond
fills and becomes a marsh…..
Ecological Succession of a Pond
Community
Eventually the marsh becomes dry land
inhabited by a stable community called a
climax community
Succession often leads to a fairly
stable collection of organisms
There are 2 types of succession that
occur in nature…..
Primary Succession
&
Secondary Succession
•Occurs in places where
no living community
existed before (ie. On a
newly formed volcanic
island)
• Occurs in areas where
natural disasters or
human activities have
wiped out a living
community
Organisms in an Ecosystem
Autotrophs
-Also called producers
-Photosynthetic and make carbohydrates
by using energy from the sun
-Most numerous organisms in an
ecosystem!
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Organisms in an Ecosystem
Heterotrophs
-Also called consumers
-Obtain energy by eating other organisms
Herbivores
Carnivores
Omnivores
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Detrivores
Decomposers
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Food Chains
A single pathway of energy transfer
is a food chain
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Food Webs
A network showing all paths of energy
transfer is a food web
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Trophic Relationships
Quaternary
Consumer
Producer
Primary
Consumer
(Herbivore)
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Tertiary
Consumer
Secondary
Consumer
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Rule of 10
Only 10% of energy is transferred
from one trophic level to the next.
Example:
-It takes 100 kgs of plant
materials (producers) to support
10 kgs of herbivores
-It takes 10 kgs of herbivores
to support 1 kg of 1st level
predators
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Energy Flow
Ecosystems contain only a few
trophic levels because there is a
low rate of energy transfer
between each level.
1.5 kJ Energy
15 kJ Energy
150 kJ Energy
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cmassengale
1500
kJ Energy
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