Functioning ecosystems and succession — Question 11

11a)

Pioneer species will move into an area and either create or improve the soil by adding organic material through their own death and decay. This makes the landscape more hospitable, allowing new species to colonise the area, changing the community composition. The community composition continues to change over time until a climax community is established.

• describes - the role of pioneer species [1 mark] - changes in community composition [1 mark] - establishment of a climax community [1 mark]

11b)

Primary succession occurs in an environment with no previous life/soil, whereas secondary succession occurs in an area that has previously been inhabited but experienced a disturbance.

• identifies a distinguishing feature of primary and secondary succession [1 mark]