G&E: Succession

Question 1

Succession

Answer 1

Process by which an ecosystem changes over time

Question 2

Primary succession

Answer 2

Happens on land that’s been newly formed or exposed, where there’s no soil or organic material.

Question 3

Secondary succession

Answer 3

Happens on land that’s been cleared of all the plants, but where the soil remians.

Question 4

Describe the stages of primary succession:

Answer 4

• Abiotic conditions are hostile - only pioneer species grow as they are adapted to cope.
• Pioneer species changes abiotic conditions - as they die, microorganisms decompose the dead organic material forming humus and basic soil.
• Conditions become less hostil.
• New organisms with different adaptions can move in.
• As they die, more organic matter is added making the soil deeper and richer in minerals.
• Larger plants like shrubs can grow.

Question 5

What is the difference between primary and secondary succession?

Answer 5

Already a soil layer, so succession starts at a later stage and pioneer species are larger plants.

Question 6

What is the final stage of succesion?

Answer 6

Climax community

Question 7

Climax community

Answer 7

The ecosystem is supporting the largest and most complex community of plants and animals it can.

It won’t change much more and is in a steady state.

Question 8

What determines which species make up the climax community?

Answer 8

The climate of the ecosystem.

Question 9

Climatic climax

Answer 9

The climax community for a particular climate.

Question 10

What does conservation often involve?

Answer 10

Managing succession

Question 11

Plagioclimax

Answer 11

When human activity stops succession artificially and prevents a climax community from developing.

Question 12

Conservation

Answer 12

The protection and management of ecosystems.

Question 13

How can succession be managed to conserve the moorland ecosystem?

Answer 13

• Allow animals to graze on the land - stops shrubs and trees establishing themselves and keeps vegetation low.
• Managed fires are lit - allows secondary succession to occur on the moorland and the pioneer species are the species that are being conserved.

Question 14

Why does conservation sometimes involve managing succession?

Answer 14

If natural processes continued, the loss of a specific type of habitat could lead to the loss of plants and animals that currently live there.