Changing Ecosystems

A community consists of all the plants and animals that occupy a particular area. The community is a constantly changing and dynamic unit, which passes through a number of stages from its origin to its climax. The transition from one stage to the next is called succession.

Succession is a process by which communities of plants and animals colonise an area and then, over time, are replaced by other, more varied organisms.

A seral community (or sere) is an intermediate stage in an ecosystem advancing through these different stages. There are two different types of succession:

  • Primary: plants grow where no plants have grown before and there is no soil.
  • Secondary: plants grow where there has been a previous population that were destroyed by something like fire.