7- Ecological Succession

Question 0

How does succession occur ?

Answer 0

Biotic conditions change as Abiotic conditions change

Question 1

What is Succession ?

Answer 1

Process of ecosystem changing over timing

Question 2

What is primary succession?

Answer 2

Land newly developed or exposed just bare rock - no organic material
E.G volcano erupts or sea level drops

Question 3

What is secondary succession?

Answer 3

Land cleared of all plants but soil remains

E.G forest fire or deforestation

Question 4

How does succession occur ?

Answer 4

1) 1st species colonise area - pioneer species - blown in by wind - seed +spores begin to grow
2) Abiotic conditions harsh - adapted to grow
3) abiotic conditions change- dead pioneer species decomposed- forms basic soil
4) condition less hostile- more soil can retain water, soil deeper +has more nutrients - new organisms move in
5) out compete previous species - better adapted to better conditions
6) SECONDARY happens same way - already soil - pioneer species are larger plants
7) as succession goes on more complex species move in - increases SD
8) final serial stage= climax community- in steady state

Question 5

How to stop succession?

Answer 5

Conservation :
•Mown grassy fields species won’t establish themselves
• animals graze field
• manage fires are lit - secondary succession occurs - pioneer species being conserved - heather

It’s done to conserve current species living there .

Question 6

Why is conserving species+habitats important ?

Answer 6

1) species are resources - drugs clothes food - not conserved - lost
2) shouldn’t become extinct cause of human activity- ethical
3) future gen. won’t be able to enjoy them
4) conserve habit + species - help prevent climate change - Eg less trees burnt
5) prevent disruption of food chains