The changes over time in species that occupy a particular area
Happens on barren land
Primary succession- happens when there is no previous colonisation
At each stage, species change the environment and allow the next species to develop
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The process of Succession
Barren land- no shelter or water
Primary colonisers (lichen) colonise areas and fix nitrogen from air. Die and decay, which provides humus for nutrients for secondary colonisers
Secondry colonisers (mosses) grow low to ground and absorb water. Secrete acid onto surface of rock, and release minerals when it is broken down
Tertiary colonisers occur when wind dispersal of seeds allows growth of roots. They cannot be blown away, and results in more competition for light, water and nutrients
Scrubland can grow now as death of plants releases nutrients and nitrates into the soil, allowing uptake of these by roots of shrubs, resulting in growth
Climax community occurs when woodland is able to grow due to nutrients being recycled from death and decay of other plants
Releases ammonium ions into the soil- converted to nitrates by nitrification
Taken up by tree roots
Stabilises community as leaf covering prevents as mcuh light reaching the ground, lessening photosynthesis of smaller plants
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