Succession

• Succession is the change in a community over time due to changes in abiotic factors and/or the species present
• Primary succession overview

  • changes from pioneer species to climax community
  • plant community alters the soil and microclimate, establishing other species
  • plant species outcompete each other
  • climax community is eventually reached where the vegetation is in a state of equilibrium with the environment and there is no further influx of new species
• Features of pioneer species

  • production of vast quantities of wind-dispersed seeds or spores to easily reach isolated areas
  • rapid germination of seeds on arrival as they don't require a period of dormancy
  • ability to photosynthesise
  • ability to fix nitrogen from the atmosphere because there aren't many nutrients available
  • tolerance to extreme conditions
• Stages of primary succession

  1. pioneer species colonise area
  2. weathering of rock and death/decomposition of pioneers produce sand or soil
  3. as pioneer species die and decompose, they add nutrients to the soil created from weathering
  4. soil becomes adequately nutritious to support a colony of small plants
  5. biodiversity increases and the environment becomes less hostile
  6. thicker layer of soil builds up
  7. small flowering plants become established
• A climax community is a stable community where no further succession occurs
• Secondary succession already has soil, nutrients and some species present so the climax community is reached quicker