Canford Heath - Plagio Climax

Question 1

What is a Plagio-Climax community?

Answer 1

A stable plant community that has arisen as a result of human intervention in the natural succession of communities.

Question 2

What are the arresting factors?

Answer 2

• Burning (controlled)
• Deforestation
• Grazing

Question 3

Location

Answer 3

Northern edge of urban area of Poole

Question 4

Characteristics

Answer 4

• 420 ha
• Lowland heath
• Typical purple heather and yellow gorse with sandy soils

Question 5

Heathland Succession - Inorganic Stage

Answer 5

No plant species
- Bare rock
- Physical weathering break down rock

Question 6

Heathland succession - Serial stage 1

Answer 6

Pioneer species
- Lichens
- Lichens can grow in the joints when algae have broken down the rock and added nutrients.
- They die adding nutrients allowing mosses and grasses to grow and then get shaded out.

Question 7

Heathland succession - serial stage 2

Answer 7

Early colonisers
- Mosses and grasses
- They break down the rock and add more nutrients

Question 8

Heathland succession - serial stage 3 (plagioclimax)

Answer 8

Late colonisers
- Heather
- Heather colonises after grasses and mosses due to greater nutrients.
- Heather shades out mosses and grasses

Question 9

Heathland succession - climatic climax

Answer 9

Late colonisers
- Scots pine and birch
- Human intervention means this not reached

Question 10

Pioneer Heather

Answer 10

• 5 years
• Moss and lichen
• Small green heather plants

Question 11

Building Heather

Answer 11

• 15 years
• Nutritious heather shoots

Question 12

Mature Heather

Answer 12

• 25 years
• Heather is dominant but becoming woody

Question 13

Degenerative Heather

Answer 13

• 30 years
• Wavy hair grass and blueberry invade the degenerating heather

Question 14

Scrub Woodland Ecosystem

Answer 14

• Grass, shrubs, trees start to also invade heather

Question 15

Climax

Answer 15

Scots pine and birch woodland

Question 16

Management

Answer 16

• Fencing to stop people (protected areas)
• Grazing and burning
• SSI, SPA, SAC status 1985 and RAMSAR site due to it’s importance

Question 17

How often should heather be burnt?

Answer 17

Every 15-25 years

Question 18

Positive human impacts

Answer 18

Burning, grazing, deforestation to maintain the heath

Question 19

Negative human impacts

Answer 19

Heathland in general
- Urban sprawl
- Invasive species
- Horse riding
- Fly-tipping

Canford
- Large housing estate spread in southern part of the heath between 1962-1980 –> springs drained and bog land dried out.
- Recreational pressure –> dog walkers - poo changes the pH of soil raising nutrient levels and therefore changing succession processes.
- Rhododendrons –> planted on Longfleet Drive invaded and spread across the reserve, shading out heather.
- 2006 –> arsonists destroyed 100ha of heath (also 2011&12) - destroy heather rootstock and expose erosion.