13.2 Succession

Question 1

Succession

Answer 1

Series of changes within a community that occur with time from its origin e.g. baron rock/sand/water to its climax community

Question 2

Pioneer species

Answer 2

Organisms that first colonise an area

Question 3

Sere

Answer 3

Complete succession from a pioneer community to a climax community

Question 4

Seral stage

Answer 4

A particular stage in succession with its own distinctive community of organisms

Question 5

Climax community

Answer 5

Final stage in an ecological succession
Stable and changes very little
e.g. woodland

Question 6

What happens in a habitat that is hostile?

Answer 6

Abiotic factors are unfavourable, few species adapted to survive in these conditions
Diversity is low and abiotic factors dominate the distribution of species
e.g. sand dunes wind

Question 7

Define abiotic and give an example.

Answer 7

Non-living parts of an environment e.g. temperature

Question 8

Diversity

Answer 8

Relationship between the number of individual organisms and the number of a species within a community

Question 9

High diversity

Answer 9

Stable ecosystem and complex food web
Population of one species in the ecosystem drops then others will be able to increase in numbers and fill the niche so the community is not affected much by the change

Question 10

Low diversity

Answer 10

Unstable ecosystem and less complex food web
If one species dies out then the whole ecosystem is disrupted

Question 11

Primary succession

Answer 11

Introduction of new plants/animals into areas that have not previously supported a community
Slower then secondary
Occurs in area devoid of vegetation and lacking soil

Question 12

Secondary succession

Answer 12

Faster than primary
Occurs after forest fires/clearance of agricultural land
Spores/seeds/vegetative organs may remain viable in the soil
Succession does not begin with pioneer species but with species from intermediate seres

Question 13

Deflected succession

Answer 13

Climax community is prevented from establishing as a result of management practices by humans
The community is maintained under conditions called a plagioclimax

Question 14

Describe the process of succession

Answer 14

• (Colonisation by) pioneer species;
• Pioneers cause change in environmental abiotic / biotic factors(give an example);
• Pioneers make the environment less hostile for new species;
• New species change/make conditions less suitable for previous species;
• Change/increase in diversity/biodiversity;
• Stability increases [population/richness/abiotic factors];
• Climax community;