Causes of Tropical Rainforest Deforestation

• Deforestation is the felling and clearance of trees

• Malaysia, Brazil, India and Indonesia are experiencing the highest levels of deforestation in the world

  • The Malaysian government has in the past failed to provide the Food and Agriculture Organisation (FAO) with figures for forest loss

• There are six main human causes of deforestation

• Wildfires are a natural cause of deforestation:

  • The frequency and severity of wildfires have increased this is linked to human induced climate change

Exam Tip

It is important to remember that deforestation is often the result of a combination of factors which are linked together rather than any one cause. For example, the growth of settlements also leads to more land being cleared for agriculture to support the people in the settlements.

Climate Change

• In addition to direct threats to the tropical rainforest there are indirect threats

• Climate change is the most significant 

  • The rainforest is dependent on high levels of precipitation 

  • Climate change impacts on the amount and frequency of rainfall

• It is estimated that the drought in 2015/16 and the wildfires that resulted led to the destruction of around 2.5 billion trees and plants

• Recent droughts have occurred in 2005, 2010, 2015/16 and 2020

• Droughts can lead to the rainforest emitting CO2 rather than absorbing it

• Droughts led to stress on the ecosystem due to

  • Decomposer organisms and insects dying as the leaf litter is too dry

    • This will lead to a decrease in soil fertility and impact on the nutrient cycle

  • Trees and plants lose more leaves than usually decreasing the supply of food

    • Fewer leaves will mean less evapotranspiration which may further decrease the amount of rainfall

  • Lack of food for herbivores reduces animal populations and impacts on the food web

  • Reduced nutrient input into streams and rivers impacts on the aquatic life

• Higher temperatures may lead to the death of animals: colonies of flying fox bats have been wiped out by increased temperature

  • This impacts on the food web