What does “succession” mean?
Jimmy Carter
1976-1980
Ronald Reagan
1980-1988
George Bush Sr.
1988-1992
Bill Clinton
1992-2000
George Bush Jr
2000-2008
Barack Obama
2008-2016
Primary Succession
• Defined: Establishment and development of an
ecosystem in an uninhabited environment
• Starts when bare rock is created or exposed
Volcanic Activity
• Lava cools and hardens into rock, creating new
land.
New barren land
Glaciers Retreat
• New land is exposed and ready to be inhabited.
New barren land
Frozen glacier
Rocky land
Pioneer Species
• Defined: First organisms to inhabit new land
• Moss and lichen grow on bare rock
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Rocky land
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Pioneer Species
• Defined: First organisms to inhabit new land
• Moss and lichen grow on bare rock
.
.
.
.
Rocky land
.
.
Pioneer Species
• Defined: First organisms to inhabit new land
• Moss and lichen grow on bare rock
.
.
.
.
Rocky land
.
.
Pioneer Species
• Defined: First organisms to inhabit new land
• Moss and lichen grow on bare rock
• Dead matter accumulates with rock pieces
– Thin soil layer begins to accumulate
Thin layer of soil
Allows more growth
soil
Rocky land
The Process Continues
• Seeds enter the area and grow
seed
soil
Rocky land
The Process Continues
• Seeds enter the area and grow
• Small flowers & shrubs accumulate more organic
matter
• With new plants, small animals and insects inhabit
the area
soil
soil
Rocky land
Even More Time Passes
• Small trees take root in the accumulated organic
matter
• More animals use the trees as a habitat
soil
soil
Rocky land
Climax Community
• Large trees take root
– Overcrowd and out-compete the original smaller trees
• New animals inhabit new forests
soil
Rocky land
Secondary Succession
• Defined: Changes/Rebuilding that take place in an
established ecosystem after a disturbance occurs
– Forest fires, floods, tree falls…
• Occurs at a faster rate (soil preexists)
Review
1) What are the first organisms to live within a newly created
patch of land called?
2) Give examples of the answer to question #1.
3) What are the final organisms to live within a newly created
patch of land called?
4) How are new areas of land created?
5) Give a few examples how the process of secondary
succession can start.
6) How does primary and secondary succession differ?
7) How is soil created?