Download Ecological Succession

Ch 4 Recap: Shaping an Ecosystem
• Community Interactions:
– Competition
– Symbiotic Relationships
• Commensalism
• Parasitism
• Mutualism
–EX. Lichen (fungus and algae)
– Predation
• Predator
• Prey
–Defense Mechanisms
Ecosystems are constantly
changing over time:
Ecological Succession
• Ecological Succession: Change is Good Crash Course Ecology #6 - YouTube
Ecological Succession
• The series of predictable changes
that occur in a community over
time.
• 2 types
–Primary
–Secondary
Primary Succession
• Succession that occurs on surfaces where
no soil exists
• Island Formed by an Undersea Volcano
• Rocks exposed when glaciers melt
• Starts with the arrival of living things such as
lichens(algae+ Fungus) that DO NOT NEED
SOIL to survive.
• PIONEER SPECIES – the first organisms to
populate an area (ex. Lichens in primary succ)
Primary Succession (Steps)
1. Making SOIL:
• Lichens and the forces of
weathering / erosion help break
down rocks into smaller pieces
• When lichens die, they
decompose, adding small amounts
of organic matter to the rock to
making soil.
Primary Succession
2. Mosses and Ferns begin growing
a. small insects move in.
Primary Succession
• The simple plants die, adding more
organic material
3. Grasses, wildflowers, and other plants
begin to take over.
a. small birds and small mammals
begin moving in.
Primary Succession
• These plants die, and they add
more nutrients to the soil
4. Shrubs and trees can survive now
a. organisms
become even
more diverse.
Primary Succession
• 5. What was once bare rock now supports
a variety of life !!!
PRIMARY SUCCESSION
Pioneer
species
Lichens
Mosses
Grasses
Ferns
Flowers
Small
Large
Trees
Trees
Shrubs
• Ecological Succession of the Climax
Forest - YouTube
Secondary Succession
• Begins in a place that already has soil
and was once the home of living organisms
• Succession that occurs after an ecosystem
was destroyed
• Occurs faster and has DIFFERENT PIONEER
SPECIES than primary succession
(common examples grasses/weeds/ferns)
Pioneer
Species
1.
Grass
2.
3.
Wild
Woody
Flowers Shrubs
4.
Small
trees
5.
Large
trees
Causes of Secondary Succession
Natural Disasters
•
•
•
•
•
Floods
Fires
Volcanoes
Hurricanes
Tornadoes
Man Made Disturbances:
•
•
•
•
•
Farming
Logging
Mining
Building
Fires?
Ecosystems MAY NOT recover
from man-made disturbances!
Climax Community
• A stable group of plants and animals
that is the end result of the succession
process
• Does not always mean big trees
– Grasses in prairies
– Cacti in deserts
Large
Trees
Glacial
Retreat
Primary
Succession
Succession in a Marine Ecosystem