Succession A2

Question 1

Define succession.

Answer 1

The process by which an ecosystem changes over time in a series of stages.

Question 2

What is a climax community?

Answer 2

The final stage in an ecological succession. Stale community, changes very little.

Question 3

Hostility

Answer 3

Abiotic factors are unfavourable, few species adapted to survive in these conditions. (diversity low)

Question 4

Abiotic environment.

Answer 4

non-living parts of environment i.e. temperature, soil mineral ion concentration, salt concentration, amount of water retention.

Question 5

Diversity.

Answer 5

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

Question 6

Succession occurs in natural ecosystems.
Describe and explain how succession occurs.
(5)

Answer 6

1. colonisation by pioneer species
2. change in environment / eg. increase in nutrients
3. enables other species to colonise/survive
4. change in diversity/biodiversity
5. stability increases / less hostile environment
6. climax community

Question 7

What occurs as a result of deflected succession?

Answer 7

1. climax community is prevented from establishing
2. such conditions on a community is known as plagioclimax

Question 8

What are pioneer species?

Answer 8

The organisms that first colonise an area. Eg. marram grass in sand dune ecosystems

Question 9

What is a sere and a seral community?

Answer 9

a complete succession from pioneer community to climax community, and a seral stage is a particular stage in this succession with its own distinctive community of organisms.

Question 10

Give 4 reasons why we should conserve wildlife and why.

Answer 10

Ecological - protect wildlife/food chains, prevent extinction, global warming, maintain biodiversity
Economic - resources (food, wood, medicine)
Ethical - not harming species
Social - human physical + mental health

Question 11

Give 6 conservation methods.

Answer 11

Protected areas - laws, permits, national parks, tagging animals
Captive breeding - reintroduce to wild
Fishing quotas
A-forestation - replanting trees
Seed banks - conserve rare plants
Manage succession to preserve ecosystem

Question 12

Name and explain 7 conservation conflicts.

Answer 12

1. Coppicing trees - can bring disease back
2. Limited area for building infrastructure
3. Quotas have an economic impact
4. Businesses want resources (palm oil etc)
5. Reduced area for farming + agriculture/deforestation for materials
6. May increase tourism (national parks) - negative effect on environment
7. Can reintroduce disease in animals when reintroduces back into new area.

Question 13

Explain what the copper cycle/sink is and benefits and drawbacks.

Answer 13

1. chop tree but leave part of trunk without damaging roots
2. tree grows back over time + can e cut down again
3. increases biodiversity when trunk is short as more light attracting new species
4. however can bring disease back

Question 14

What adaptations do pioneer species tend to have? (5)

Answer 14

1. A tolerance to extreme conditions
2. The ability to fix nitrogen from the air
3. Ability to photosynthesis light.
4. Can easily disperse seeds across vast distances
5. Rapid germination of seeds