Ecological Succession
Ecological Succession
• Definition of
succession:
The regular
progression of species
replacement in a
changing ecosystem
(= stages/steps of an ecosystem
changing as different species
replace others)
Types of Succession
• Primary Succession
• Secondary Succession
• Takes place in areas
• Takes place in an area
that have not
that had once supported
supported
communities
communities before or
no life exists anymore
Primary Succession
• Starts with:
–
–
–
–
•
Bare Rock
Lava Flows
Sand Dunes
Clear/cold Lakes
http://www.hawaiipictures.com/pictures/volcano_lav
a.html
Primary Succession
• First species to show
up in the community is
called the
Pioneer Species
Lichens and Moss Native Prairie Grass
Succession
• Each intermediate community that
appears after the pioneer species is called
a Seral Community.
• Each seral community alters the physical
factors of the area
• May have small shrubs, start to have trees
such as Jack Pine and Aspen
• May have small animals such as rabbits,
squirrels, deer
Succession
• The last community to show up
in an area is called the
Climax Community.
• This community is stable and
permanent. A state of
homeostasis has been met.
• May have large trees such as
Balsam Fir and White Spruce
• May have animals such as elk,
bear, wolves, owls.
http://www.blueplanetbiomes.org/deciduous_forest.htm
Types of Secondary Succession
• Usually occurs after a
disturbance or natural
disaster
• EX: fire, landslides,
floods, wind, farming
•
http://www.sover.net/~kenandeb/fire/hotshot.html
Primary Vs. Secondary
Succession
• Secondary Succession tend to develop faster
because typically there is already a soil or
nutrient base present – there may even be
some seeds or other dormant life.
• Both types of succession go through similar
phases of pioneer, seral, and climax
communities.
Primary Succession
Exposed
Lichens
rocks
and mosses
Small herbs
and shrubs
Heath mat
Time
Jack pine,
black spruce,
and aspen
Balsam fir,
paper birch, and
white spruce
climax community
Fig. 8.15, p. 188
Secondary Succession
Mature oak-hickory forest
Young pine forest
Annual
weeds
Perennial
weeds and
grasses
Shrubs
Time
Fig. 8.16, p. 189
Oligotrophic Lake
• Succession of lake
starts with a lake that
does not have a lot of
nutrients in it.
• Characteristics:
– Cold, Clear water
– Support few Species
– Not much biomass
•
http://www.satirewire.com/news/july02/viagra.shtml
Eutrophic lake
• Process of adding nutrients
to a water ecosystem is
called Eutrophication.
This results in a lake that
• has a lot of nutrients
• Is Warm
• Looks “Dirty” or “Cloudy”
• Supports many species
• Lots of Biomass
Fig 10.7 Diagram of bog
succession.
© 2003 John Wiley and Sons Publishers