Ecological Succession Notes

Ecological Succession  Gradual replacement of simple organisms with more complex organisms overtime  Role of succession is to make an ecosystem more sustainable/biodiverse  Can happen in a microhabitat, like a garden being taken over with weeds  No organisms OR small plants & insects  grass, rabbits  shrubs/bushes  Forest

Pioneer Species – first organisms to arrive in an area

Climax community  The oldest stage of succession  The most stable/balanced ecosystem  Example: Forest (depends on the biome)  Number of species plateaus or remains constant

Invasive Species (non-native)  New species to an area that do not have any natural predators/enemies  Population grows uncontrollably  Replaces other species, native species population decreases  Examples: weeds like dandelions, zebra mussels

Eutrophication – succession in an aquatic area that can turn it into land

Primary Succession

 Begins in a place without soil; ROCK  Events that trigger: Volcanic Eruptions (lava hardens into rock), Rock slide  Pioneer Species – Lichen and moss (grow in extreme conditions; break down rock into soil)  Can reach a climax community in 1,000 years  ROCK  Lichen & Moss  Grass  small plants & insects  grass, rabbits  shrubs/bushes  Forest  Change in number of species is very slow at the beginning

Secondary Succession

 Begins in an area that only has SOIL, but used to have organisms  Events the trigger: Construction (bulldozing or clearing land), Natural disasters like floods or hurricanes  Pioneer Species – Grass (seeds are already in soil or brought in by wind/water/animals)  Can reach a climax community in 100 years  Grass  small plants & insects  grass, rabbits  shrubs/bushes  Forest  Change in number of species happens at a steady rate