Succession and conservation (BIOL4)

Question 0

What is primary succession?

Answer 0

Succession on newly formed land No soil to start with

Question 1

Define succession

Answer 1

Gradual change in communities

Question 2

What is secondary succession?

Answer 2

Succession on cleared land Soil remains

Question 3

Features of succession

Answer 3

• First seral stage - primary succession starts when spores/seeds blown by wind/grow
  
  • first colonising species called pioneer species
• Abiotic conditions hostile (no soil) - only pioneers grow: adapted to conditions
• Pioneers change abiotic cond. - die and decomposed material forms basic soil
• Make cond. less hostile - new organisms grow, die and decomposer to make deeper soil
• Secondary succession occurs at later stage: At each stage, diff plants/animals better adapted move in and out-compete w/ others present
  
  • become dominant in ecosystem
• Ecosystem becomes more complex - more species move in, species diversity inc.
• Final seral stage - climax community:
  
  • ecosystem largest, most complex and in steady state

Question 4

Define plagioclimax

Answer 4

Succession prevented artificially

Question 5

What is conservation?

Answer 5

Involved preventing succession to preserve an ecosystem in the current seral stage

Question 6

Why is conserving species important?

Answer 6

Species used for resources

Moral/ethical Aesthetic reasons (tourism)

Prevent climate change

Question 7

Describe conservation methods

Answer 7

Seedbanks - for extinct plants, seeds are grown, but you need to test seeds

Fishing quotas - prevent overfishing

Captive breeding programmes

Relocation

Protected areas - restrict urban/industrial growth