Primary Succession
• Defined:
Defined: Establishment and development of an Establishment and development of an
ecosystem in a previously uninhabited environment
– Volcanic lava creates new land
Volcanic lava creates new land
– Glaciers retreating exposing new land
Example of Creation of Bare Rock
Pioneer Species
• Defined: First organisms to inhabit new land
Lava cools and hardens into rock
– Begins with bare rock
• Moss and lichen grow on bare rock
– Dead
D d matter
tt accumulates
l t with
ith rock
k pieces
i
• Thin soil layer begins to accumulate
The Process Continues
• Seeds enter the area and grow
• Grasses,
G
smallll flowers
fl
& shrubs
h b
accumulate more organic matter
• With new plants,
l t smallll animals
i l iinhabit
h bit th
the
area
Climax Community
• Large trees take root
– Overcrowd and out
out-compete
compete original trees
• New animals inhabit new forests
The Process Continues
• Small trees take root in the accumulated
organic matter
• More animals use the trees as a habitat
Example of Primary Succession
Example of Primary Succession
Secondary Succession
• Changes that take place after a disturbance occurs in
an established ecosystem
– Forest fires,
fires floods,
floods tree falls…
falls
• Re-growth happens on a faster scale (soil preexists)
Example of Secondary Succession
Using the pictures that follow this slide:
• Explain what is happening in each
stage of secondary succession.
• Describe which stage will come next
and why
why.
Example of Secondary Succession