Succession

Question 1

what does a dynamic ecosystem mean?

Answer 1

It is constant changing

Question 2

What is succession?

Answer 2

the process by which an ecosystem changes over time

Question 3

Generally, what happens at each stage of succession?

Answer 3

The plant and animal communities in an area slowly change the environmental conditions, making the conditions more suitable for other species with different adaptations

Question 4

What changes as the abiotic conditions change?

Answer 4

The biotic conditions change

Question 5

What are the two types of succession?

Answer 5

Primary

Secondary

Question 6

Where does primary succession happen?

Answer 6

On land thats been newly formed or exposed

There is no soil or organic material to start with, just bare rock

Question 7

When does primary succession happen?

Answer 7

When species colonise a new land surface

Question 8

How does the pioneer stage of succession happen?

Answer 8

Seeds and spores are blown by the wind and start to grow

Question 9

What is a pioneer species?

Answer 9

The first species to colonise a land

Question 10

What are the abiotic conditions like at the pioneer stage of succession?

Answer 10

Hostile and only pioneer species can grow because they are adapted to cope with the harsh conditions

Question 11

What are some examples of adaptations which pioneer species might have?

Answer 11

Deep roots to get water
Secrete acids which erode rocks to release minerals
Adapted to live in periodic droughts

Question 12

What do pioneer species change?

Answer 12

The abiotic conditions

Question 13

How do pioneer species change the abiotic conditions?

Answer 13

They die and micro-organisms decompose the dead organic material which forms a basic soil, making the conditions less hostile

Question 14

What is the role of nitrogen fixing bacteria in the pioneer stage of succession?

Answer 14

They turn nitrogen into the atmosphere into ammonia which form ammonium ions in solution

Question 15

Once the species after the pioneer species have habited the area, what happens to the conditions?

Answer 15

They die and decompose which adds more organic material, making the soil deeper and richer in minerals

Question 16

How is having ammonia ions in solution in the soil beneficial?

Answer 16

Larger plants such as shrubs can start to grow in the deeper soil which retains even more water and contains more nutrients

Question 17

What becomes more complex as succession continues?

Answer 17

The ecosystem

Question 18

In the later stages of succession, what happens at each stage, generally?

Answer 18

Different plants and animals that are better adapted for the improved conditions move in, out-compete the plants and animals that are already there and become the dominant species

Question 19

What is a climax community?

Answer 19

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

Question 20

Will the ecosystem change much after its reached its climax community?

Answer 20

No - its in a steady state

Question 21

What is secondary succession?

Answer 21

Takes place on land thats been cleared of all plants but the soil remains

Question 22

What event might cause secondary succession?

Answer 22

Forest fire

Deforestation

Question 23

What is plagioclimax?

Answer 23

Humans artificially stopping a climax community from developing further

Question 24

What is the climatic climax?

Answer 24

The climax community for a particular climate