What is the definition of Ecological Succession?
• The gradual process of change and replacement of some or all of the species in a community
What is primary succession?
• A type of succession that occurs on surface where no ecosystem existed before
Describe the steps of primary succession on a rock base.
• Lichens colonize rock• Lichens begin to break down rock, soil begins
to form• Weathering helps break down rock adding to
soil• Some Lichens die, adding nutrients to soil• Moss starts to grow on rocks• Some moss dies, adding more nutrients to soil
What is secondary succession?
• A type of succession that occurs on a surface where an ecosystem has previously existed, it occurs after there is a disturbance to the first ecosystem.
Name 3 examples of disturbances that could occur before secondary succession
would begin?
• Fire• Hurricane• Clear cutting for farming• Floods• Volcanoes• building
What is a pioneer species?
• The first organisms to colonize any newly available area and begin the process of ecological succession
After Mount St. Helen erupted the prairie lupine colonized the habitat, how did the lupine make the habitat more habitable
for other plants?
• It “fixed” nitrogen, adding usable nitrogen to the soil
How have animals assisted in the secondary succession of
Mount St. Helen?
• By bringing seeds to the ecosystem, either by carrying them or through their waste
What are the steps in old field succession?
• Pioneer grasses and weeds grow• Taller plants grow, shade out smaller ones
which die• Trees start growing, shade out taller plants
which die• Even taller trees take over• After about 100 years, land may return to
climax community
In a coral reef ecosystem what species was present in the climax community that wasn’t present in
the other reefs?
• Shark
What are examples of natural disturbances that destroyed part of the coral reefs?
• Hurricanes and El Nino