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Succession
Jessica Panicker and Kellie Egan
Key Terms To Know
● Pioneer Species-species which
are the first to colonize previously
disrupted or damaged
ecosystems, beginning a chain of
ecological succession
● Climax Community- a stable
mature community
Climax Communities
● The trees found in climax community are hardwood
trees
● Soft wood trees are found before climax community
● Shade-tolerant trees are found in later stages of
succession
Primary Succession
● Primary succession is the colonization of
living organisms into an area that was not
previously colonized by any living things.
● Example: succession occurring after a
glacier recedes or after a new
island forms from
oceanic volcanoes
Secondary Succession
● Secondary succession is the regeneration of
the living community after a major disturbance.
● Example: after a forest is clear-cut the trees are
removed but some small plants, the soil, and
soil organisms remain.
The forest will
slowly regenerate.
Primary vs. Secondary Succession
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Primary
Begins with no life
No Soil Present
Lichen and moss comes
first (pioneer species)
Biomass is low
Requires more time to
reach the climax
community
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Secondary
Follows removal of
existing life
Soil already present
Old Area
Seeds and roots already
present
Biomass is higher
Requires less time to
reach the climax
community
Pros and Cons of Succession
Pros
● creates an ecosystem that
is balanced and stable
● restore an environment
after it has been disturbed
by clear-cutting, forest
fires, etc.
● prevents desertification
● promotes biodiversity
o pros of biodiversity
Cons
● Slow process
● If there is another
disturbance, the process
starts over
● can lead to habitat loss for
some species
o species that relies on
early succession
species
How this Relates to
Forest Management
Clearcutting
● Clearcutting is the removal of all trees
within a designated area.
● Clearcutting removes all existing life in the
area but NOT the soil
● Secondary Succession
Forest Fires
● Forest Fires burn down matter in the area
● Although all is burnt, the soil still remains
● Secondary Succession
Old Growth Forests
● Old growth forests have large trees and
multilayered canopies.
● Well developed
● Climax Community
Strip Cutting
● Strip cutting is when you cut a strip of
trees down in a forest, leaving trees on
either side of the strip.
● Secondary Succession
Volcanic Eruptions
● After a volcanic eruption, lava hardens
and covers the ground.
● This is primary succession because the
lava creates a layer of rock
Future Outlook
● Bright Future
● Will continue to be Earth’s natural
restoration process
o clear-cutting, forest fires, strip-cutting
continues
● Conservationists continue to monitor
ecological succession to be able to detect
environmental change in an area.