Paper 3 Flashcards
What is the Malthusian theory?
That human population grows faster than food supply and as a result, disasters will occur e.g. war and famine
Is the Malthusian theory reliable?
Malthusians will point to recent wars and breakouts of Ebola etc.
How could you argue against the Malthusian theory?
- That food and resource production methods have become more efficient and able to create larger amounts
- That as economies have developed their birth rates have fallen
What is the Boserupian theory?
That as demand reaches an unsustainable level, human intelligence will solve the issue
Is the Boserupian theory reliable?
- Boserupians will point out that in the 20th century the population increased to 6 billion people and there has not yet been a population crash
- Green revolution - improvements of farm machinery, pesticides and selective plant breeding
How could you argue against the Boserupian theory?
Talk of how there is an AIDs pandemic and a rapid increase in refugees fleeing fighting and war zones
What percentage of the world’s species live in the TRF?
Between 50% and 90%
What are reasons for high biodiversity in the TRF?
- Conditions for plant growth are very good
- They are ancient ecosystems and have been supporting species for thousands of years
(6) What are adaptions of the flora in the TFR?
- Layers of the rainforests
- Drip tips
- Emergent
- Buttress roots
- Lianas
- Epiphytes -
What is an epiphyte?
an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water
What are lianas?
long-stemmed, woody vines that are rooted in the soil at ground level and use trees, as well as other means of vertical support, to climb up to the canopy to get access to well-lit areas of the TRF
What are buttress roots?
large, wide roots on all sides of a shallowly rooted tree
What are drip tips?
waxy, downward facing leaves that prevent moisture from accumulating and causing mould to grow
(4) What are fauna adaptations in the TRF?
- Monkeys prehensile tails - climbing
- Green Boas ability to hang from the branch
- The sloth has strong claws - defence
- Toucan with its strong beak
(4) What are direct threats to the TRF?
- Deforestation
- Commercial agriculture
- Subsistence agriculture
- Mining
What is an indirect threat to a TRF?
Climate change
3 facts about deforestation:
- Around half of the rainforests in the world have been cleared
- In 2006 an estimated 7.3 million hectares were cleared - 36 football pitches a minute
- If deforestation continues at this rate all TRFs will be gone in 100 years
What is commercial agriculture?
When crops are grown and sold for profit. Most of the Amazon is cleared for cattle farming - Brazils main export is beef
What is subsistence agriculture?
When people clear the TRF for themselves - increasing as population increases
What is commercial hardwood logging?
When rainforest timber is sold and is very expensive. Many countries have laws preventing this, however there is still illegal trade
What 3 things cause hardwood logging?
- Corrupt police and governments
- Demand is high for hardwood timber such as rosewood and mahogany
- Locals are often poor and see it as a way to make money
How does the warming climate affect the TRF?
The warmer temperatures are causing less rainfall as climatic conditions are shifting toward the poles - less rainfall and more droughts
What would seasonal weather do to rainforests?
- There will be less resistance to new pests and diseases
- More species would become extinct as they won’t be able to survive the climate changes