Download Chap. 16 Ecosystems

Chap. 16
Ecosystems
What is an Ecosystem?
Section 1
Interactions of Organisms and
Their Environment
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Ecology – the
study of the
interactions of
living organisms
with one another
and with their
physical
environment
Habitat – the place
where a particular
population of a
species lives
Levels of Organization

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Organism – an
individual living
thing
Population – a
group of the
same species
that lives in one
area
Community – the
many different
species that live
together in a
habitat
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Ecosystem or
ecological system –
consists of a
community and all
the physical aspects
of its habitat –
complex web of
connected biotic &
abiotic factors
Biome – a major
regional or global
community of
organisms
Keystone species
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Is a species that
has an unusually
large effect on its
ecosystem
Form and maintain
a complex web of
life
Affects all the
other species
connected to it
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Biosphere – living
globe – that part of
the Earth in which life
exists
Extends to as far as 8
kilometers above the
Earth’s surface to as
far as 8 kilometers
below the surface of
the ocean
Organisms are not
distributed uniformly
throughout the
biosphere
Factors of An Habitat
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Abiotic factors
– physical
aspects of a
habitat –
natural
nonliving
Biotic factors –
the organisms
in a habitat
Physical Aspects
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Terrain
Water
Soil
• Minerals
• Composition
• Organic matter
• pH

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Air atmosphere
Weather/climate
Intensity of
sunlight
Diverse Communities in Ecosystems

Biodiversity –
the variety of
organisms,
their genetic
differences,
and the
communities
&
ecosystems
in which they
occur
Ecosystem Inhabitants of a Pine
forest

Which of the six
kingdoms of
organisms would
be represented if
you fenced a
square kilometer of
the forest?
Ecosystem Boundaries

Physical
boundaries of an
ecosystem are not
always obvious,
also depends of
ecosystem being
studied
Change of Ecosystems over Time
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Pioneer species – the
first organisms to live
in a new habitat
where soil is present
Tend to be small,
fast-growing plants
examples: lichen,
mosses – can break
down solid rock into
smaller pieces
Make the ground
more hospitable for
other species
Succession

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Succession –
regular progression
of species
replacement
Regenerate a
damaged
community or
create a
community in a
previously
uninhabited area

Primary
succession –
occurs where
life has not
existed
before
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Secondary
succession –
occurs in areas
where there has
been previous
growth
Reestablishment
of a damaged
ecosystem
Small
disturbances
start the process
Again & again
Climax Community

which populations of
plants or animals
remain stable and
exist in balance with
each other and their
environment. A climax
community is the final
stage of succession,
remaining relatively
unchanged until
destroyed by an event
such as fire or human
interference

http://glencoe.mcgrawhill.com/sites/0078802849/student_
view0/unit1/chapter3/concepts_in_m
otion.html#
Pond Succession

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http://www.sabah.ed
u.my/csm07010/Form
%204/pond.htm
Pond succession
occurs due to the
change in depth of
the pond. When
submerge plants die,
it will deposit at the
bottom of pond. Over
the time, the pond
becomes shallow until
finally filled in.