Rainforests

Question 1

Where are tropical rainforests found?

Answer 1

Between 0 - 23 1/2° north and south of the equator. Aka the tropics of cancer and capricorn. Brazil, Central Africa and through out Asia

Question 2

What are the main characteristics of the climate of a tropical rainforest area?

Answer 2

• temperature must be over 25°C
• minimum annual rainfall is 1700mm

Question 3

How has rainforest vegetation adapted to the climate?

Answer 3

• emergent trees - grow to heights of 50m to reach sunlight
• large buttress roots - stand above the ground to give support for the trees
• lianas - vine like plants that grow on large tree trunks
• leaves have drip tips - to shed the heavy rainfall
• shrubs on undergrowth - adapted to lack of light, there are little, 1% of sunlight reaches floor

Question 4

What are the causes of deforestation in the Amazon rainforest?

Answer 4

FARMING
- subsistence farming
- slash and burn (Ameridians)
- cattle ranching, TNCs, commercial fast food chains

SETTLEMENT
- population increase, from 2 to 30 million

TRANSPORT
- 1200km of roads built
- 900km railways
- airstrips

EXTRACT RESOURCES
- HEP
- timber
- minerals, e.g. diamonds, bauxite, gold, iron ore

Question 5

What are the local effects of deforestation in the Amazon?

Answer 5

DECREASE IN BIODIVERSITY
- 10km^2 contains 1500 flower species, 400 bird and 750 tree

IMPACT ON NUTRIENT CYCLE
- no canopy, so less interception, more surface run off, soil erosion (less fertile)

RIVER POLLUTION
- due to mining, impacting aquatic life

AMERIDIANS
- pop decrease by 200,000

Question 6

What are the global effects of deforestation in the Amazon rainforest?

Answer 6

CLIMATE CHANGE
- decrease rainfall,- drought
- increase CO2 - increase greenhouse effect - increase temp

INCREASED TEMP
- extreme weather
- rising sea levels
- melting ice caps

One third of world fresh oxygen from rainforests