Ecological Succession

Question 1

Succession

Answer 1

The change in an ecosystem or biological communities structure over time.

Question 2

Primary succession

Answer 2

Occurs over broad time scales where bare areas are colonised for the first time, such as on lava flows, new sand dunes, new coral reefs and land exposed by retreating glaciers.

Question 3

Secondary succession

Answer 3

Occurs over short time scales in previously vegetated areas where there has been a disturbance that resets the community to an earlier stage of succession. (Note: disturbances can include natural disasters such as wildfires or floods, human impacts or smaller events such as a tree falling in a rainforest).

Question 4

Three major successional stages (seres)

Answer 4

Pioneer species (eg. fast growing grasses, lichens or ferns) colonise the new or recently exposed substrate

Intermediate species regrow or seeds germinate / grow from seed store in soil (eg. shrubs and small trees such as wattles and she oaks)

Mature forest (climax) species develop as nutrient level and micro-habitats develop overtime