1B - Tropical Rainforests

Rainforests Key Characteristics

- Incredibly high biodiversity (6% earth/ 50% living organisms)

- Hot + Humid

- High rainfall

- Infertile soil (leaching from all the rain and rapid nutrient uptake)

Rainforest stratification (layers)

- Emergent trees receive most light - straight/branchless trunks

- Canopy - dense leafy roof where most organisms live

- Undercanopy - layer of shorter trees/shrubs (drip tips)

- Shrub level - dark, damp, covered in decaying matter

Why should tropical rainforests be protected? (4)

- Biodiversity (>half animals & plants in the world)

- Climate change (trees)

- People (indigenous tribes)

- Medicinal potential (25% of all medicines from rainforest plants)

Sustainable Management of Rainforests (4 ways)

1. Selective logging and replanting - (avoids clear felling - used in Malaysia)

2. Conservation and Education - (e.g. for research or tourism like Brazil national parks)

3. Ecotourism - (e.g. Malaysia - provides long term income for locals and government)

4. International Agreements - (debt-for-nature-swapping - debt relief in return for stopping deforestation)

Malaysia Facts

- South-east Asia

- 67% rainforest

- Deforestation rate increasing faster than any other tropical country in the world

Malaysia Threats & Causes - Logging

- 1980s largest exporter of tropical wood (high valued)

- BUT clear felling has recently been replaced with selective logging of mature trees

- Roads must be built to provide access to logging, mining, new settlements and energy projects

Malaysia Threats & Causes - Mineral Extraction

- Primarily tin mining

- Drilling for oil and gas recently started

Malaysia Threats & Causes - Population Pressure

- Poor people in urban areas encouraged to move away into countryside --> space needed

- Immigration from waves after world wars --> more space needed

Malaysia Threats & Causes - Commercial Farming

- 2nd largest exporter of Palm Oil in the world

- 10 year tax incentives for more deforestation and plantation

Malaysia Threats & Causes - Subsistence Farming

- 'Slash and burn' methods of deforestation can cause huge fires which destroy large areas of forest

Malaysia Impacts - Biodiversity

Global:

- Loss of habitats --> extinction

- Loss of medicinal potential

- Loss of plants --> valuable hardwoods/nuts/fruit/rubber

Malaysia Impacts - Soil Erosion

Local:

- After deforestation, top layer more exposed to rain/wind

- Soil is not bound together by plant roots

- Fertile soil is eroded by rain/wind

Malaysia Impacts - Climate

Global:

- Trees absorb co2, so less trees = more co2

- When cut, trees release their co2 store into atmosphere

Local:

- Trees give off moisture through transpiration

--> less trees = reduces air moisture --> drier and hotter

Malaysia Economic Gains

- Jobs for mining/farming

- Tax revenue used for social services e.g. education

- Improved infrastructure and new places for tourism

- Valuable minerals

- Plantation products support processing industries e.g. palm oil and shampoo

- Space for energy production plants e.g. hydroelectric

Malaysia Economic Losses

- Plants with medicinal qualities could've been used for profit

- Climate change has economic costs e.g. more extreme weather

- Fires cause pollution and destroy areas of valuable forest

- Rising temperatures could affect crops

- Money made from rainforest tourism could decrease

- Water pollution combined with drier climate can lead to water shortages