The climatic climax: temperate deciduous woodland Flashcards Preview

A level Geography - Ecosystems: change and challenge COPY > The climatic climax: temperate deciduous woodland > Flashcards

Flashcards in The climatic climax: temperate deciduous woodland Deck (18)
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1
Q

What is an example of a high-energy biome?

A

Tropical rainforests and temperate deciduous forests.

Own distinctive vegetation.

2
Q

What is an example of a low-energy biome?

A

High altitude - tundra.
Low altitude - desert.
Scant vegetation.
Low NPP.

3
Q

What is a biome considered to be in its natural state?

A

In dynamic equilibrium with its environment.
The vegetation exists in perfect balance with the climate and soils and that any change would alter the balance between the components of the biome.

4
Q

What are the characteristics of a temperate deciduous forest? FIRST SIX FACTS:1/2.

A
  1. NPP – 1,200g dry organic matter per m squared per year.
  2. Taller trees - dominant species e.g. Oak – 30/40m, followed by elm, beech, sycamore, ash and chestnut.
  3. Large crowns and broad but thin leaves.
  4. Deciduous trees shed leaves in winter – reduces transpiration.
  5. Few dominant species – some woodlands are only dominated by one tree species.
  6. Oak - 20m, mosses - 2cm, bramble - 1.5m.
5
Q

What are the characteristics of a temperate deciduous forest? SECOND SIX FACTS: 2/2.

A
  1. Stratification.
  2. Below the canopy - shrub layer with smaller trees e.g. holly and hawthorn.
  3. Herb layer - dense if enough light filters through the shrub layer e.g. grass and bluebells.
  4. Epiphytes grow on trunks/branches e.g. mosses.
  5. Thick leaf litter layer - broken down by soil microbes/animals.
  6. 10C, 30-60 inches of rainfall per year.
6
Q

What human activity creates plagioclimaxes? 3

A
  1. Deforestation/afforestation.
  2. Animal grazing/trampling.
  3. Fire clearance.
7
Q

When does a secondary succession occur?

A

Previously vegetated land.
E.g. area cleared for farming, but later abandoned.
More rapid stages than primary succession - organic matter already present.
Pioneer stage is short/absent altogether.
Climatic climax - reached sooner.
Occur due to a climate change, disease etc.

8
Q

What is an example of a UK plagioclimax and how has it developed into a plagioclimax?

A

Heather moorland.
Once covered by climax vegetation - removed by deforestation.
Heather - originally featured in tiny amounts.
Soil deteriorated - heather became dominant.
Sheep grazing major agriculture form - prevents climax woodland regeneration - destroys young saplings.

9
Q

What are the 4 BASIC stages within a heather cycle?

A
Pioneer phase (0-6 years).
Building phase (6-15 years).
Mature phase (12-28 years).
Degenerate phase (20-30 years).
10
Q

Explain the pioneer phase of a heather plagioclimax.

A

0-6 years.
Small shoots among dead heather stems.
Other plants present - mosses and lichens.

11
Q

Explain the building phase of a heather plagioclimax.

A
6-15 years.
Dense dome-shaped plant.
Flowers profusely.
Little light penetrating to ground.
Heather dominant.
Few other plants.
12
Q

Explain the mature phase of a heather plagioclimax.

A
12-28 years.
Reduction in vigor.
Stems tough/woody,
Some light penetrating to ground.
Colonisation of other plants.
13
Q

Explain the degenerate phase of a heather plagioclimax.

A

20-30 years.
Gaps enlarged.
Few new shoots.
Mosses, lichens and grasses in gaps.

14
Q

How has the UK heather plagioclimax been controlled?

A

Managed burning - encourages new heather shoots.
Eliminates less fire-resistant species - heather dominates.
Burnt every 15 years.
Left any longer - too much woody tissues - fires burn too hot - lost nutrients.

15
Q

What would happen if heather burning didn’t occur?

A

Heather moorland degenerates.
Climatic climax regeneration.
Majority present UK - plagioclimax - clearance of the Roman/Ango-Saxon periods.

16
Q

Why does vegetation grow quickest in a tropical rainforest biome?

A

Constant high temperature and rainfall.

Greatest amount of organic matter (NPP).

17
Q

What is the NPP for:
Tropical rainforest.
Monsoon forest.
Savanna grassland.

A

2,200 g m-2 year-1.
1,600 g m-2 year-1.
900 g m-2 year-1.

18
Q

Where is the world’s greatest biodiversity found?

A

Tropical rainforests - contains half the world’s gene pool.
Stable ecosystems - 100 million years.
Undisturbed state - gained new species.