succession

• ecological succession is the natural changes in an ecosystem overtime
• there are two types of succession:

  • primary - from bare rock/sand/gravel from volcanoes and glaciers retreating
  • secondary - from soil that contains organic matter
• the first stage is bare rock exposed by volcanoes and ice
• stage 2 is pioneer species like lichen growing on rock faces because it is tough and hardy
• stage 3 is mosses and ferns using built up dead organic matter in cracks
• stage 4 is the growth of grasses and ferns from the accumulation of dead organic matter storing water and nutrients
• stage 5 is a climax community where pioneers are outcompeted by trees and other large plants by the soil accumulating enough.
• a climax community is where plants in equilibrium with the environment