Succession

Question 1

how does succession occur

Answer 1

1.      (Colonisation by) pioneer (species);
2.      Change in environment / example of change caused by organisms presentto make lesshostile
3.      Enables other species to colonise / survive;
4.      Change in diversity / biodiversity;
5.      Stability increases / less hostile environment;
6.      Climax community;
Example of change e.g. formation of soil / humus / organic matter / increase in nutrients;

Question 2

what are the two types of succession

Answer 2

primary and secondary

Question 3

what are the characteristics of primary succession

Answer 3

the starting point is bare ground e.g. rock

Question 4

what are the characteristics of secondary succession

Answer 4

Here a community is damaged and the soil is left. Plants then colonise
(e.g. a woodland has been felled).

Question 5

what happens in sere 1

Answer 5

Very specialised species live in this area, they are called PIONEERS

These species are highly adapted to hostile conditions…
They are slow growers
As they grow they stabilise the ground (roots) and through decay they add nutrients to the ground

Question 6

what happens in sere 2

Answer 6

Now the abiotic conditions are improving (humus etc) more different species can grow. This increases biodiversity. (more different habitats & food)
They out-compete the pioneer species.

Question 7

what happens in sere 3

Answer 7

After a few hundred years, a climax community is formed.
They are large plants, often trees and will block the light so there are less smaller plants (lower biodiversity) BUT most stable

Question 8

what is conservation

Answer 8

Conversation is the maintenance of biodiversity,, genetic diversity within species and maintenance of a variety of habitats and ecosystems.

halting succession, to preserve species that would be extinct by the climax community being established

Conserving habitats by managing succession eg. Felling trees, using animals to graze the ground or controlled fires