Transcript Succession PPT notes

Equilibrium in Ecosystems
 Succession
is the series of
predictable changes that occur in
a community over time.
 Succession helps an ecosystem to
recover and return to a state of
equilibrium after a fire, volcano or
other disaster.

There are two types of succession:
Primary
and
Secondary
 Primary
Succession occurs where
no ecosystem previously existed.


New Volcanic Island
Area of Rock Uncovered
by retreating Glaciers
A
new island is formed through
long series of volcanic eruptions.
No life exists on this new rocky
material at first.
What will you draw here to represent the
beginning of primary succession?
Year
Zero


The newly created island is made of
volcanic rock, but no soil.
Most large plants with roots
can’t grow without soil.
Most animals can’t survive without
plants, so how can life exist on this
new island?

Small plants like lichens and mosses do not
have roots. These small plants have the
ability to grow on rocks and slowly breakdown the rocks to produce soil.
What type of plants do you think will
first reappear? Draw them here.
Year
Zero
Months to
years
later

The newly produced soil can now start to
support small plants with some degree of
roots systems.
Grasses with
small root systems
will typically start
to grow next.



As more plants grow, the roots of the plants
break down the rock further to produce richer
and more abundant soil.
Succession continues with larger plants now
having the ability to grow.
On many islands, ferns
will now begin to grow.
Think about what you know about
succession, then draw what type of
plant you now think will grow in this
area
Year
Zero
Months to
years
later
Years later
Over time, larger and more
complex plants will begin to grow.
Flowering plants will now be seen.


The types of producers become more varied
and this sets the stage for animals to be able
to survive.
Larger and larger plants now grow, providing
food, shelter and nesting places for a variety of
animals.
Many different
types of trees
now begin to
grow.
Add to your Timeline in Your NB
After many years have passed, what type
of plants will now be found in this area if no
other disturbances occur? Draw these
here.
Year
Zero
Months to
years
later
Years later
Many
Years
Later
What will you draw here to represent the
beginning of secondary succession?
Year
Zero
Secondary Succession occurs following a
disturbance to an ecosystem, such as after a
devastating fire.


Secondary succession occurs
naturally after hurricanes,
floods, and tornadoes.
Secondary succession also occurs after
farming, logging and mining have disturbed an
ecosystem.



Secondary succession occurs in a place
where an ecosystem has previously existed.
Secondary succession can happen faster
because soil has already been produced.
If soil was not lost in the disturbance, plants
can grow more quickly.
Large plants eventually overtake the
island.
Monkey Pod Tree
The renewed ecosystem is now full of
varied types of life, plants and animals
live successfully together.
The Ecosystem Once Again
Reaches Equilibrium
What will you draw here to represent the
events that happen in secondary
succession?
Year
Zero