Causes and Impacts

• Causes of deforestation


  • Wildfires
  • Expansion of settlements
  • Logging
  • Clearing land for agriculture
  • Mining
  • Infrastructure development
• The frequency and severity of wildfires have increased, which is linked to human-induced climate change
• 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
• Wildfires are a natural cause of deforestation
• The frequency and severity of wildfires have increased, linked to human-induced climate change
• Main human causes of deforestation

  • Wildfires
  • Logging
  • Energy (dams, mining)
  • Commercial plantations
  • Settlements
  • Subsistence farming
• Deforestation leads to areas being planted with monoculture, which reduces biodiversity
• Deforestation decreases interception and infiltration

  Reduces evapotranspiration and precipitation
• Deforestation increases overland flow

  Leads to soil erosion and sedimentation of rivers
• Sediment builds up on riverbeds, reducing their capacity and increasing flood risk
• Lack of interception increases the leaching of nutrients from the soil
• Fewer trees increase the amount of CO2 in the atmosphere


  Adding to the enhanced greenhouse effect
• Soils become less fertile and drier, may turn reddish brown due to increased iron oxide
• The majority of nutrients in the tropical rainforest are held in the biomass, which is removed by deforestation
• Indigenous communities have less land to sustain their traditional way of life, leading to a loss of culture and traditions
• Deforestation increases the risk of landslides and flooding of settlements
• Deforestation leads to a loss of potential medicines
• Deforestation provides more jobs in mining, forestry, agriculture and hydroelectric power
• Almost a quarter of Brazil's GDP comes from activities in the deforested areas of the Amazon
• Malaysia has the fastest rate of deforestation in the world, with over 140,000 hectares of forest felled and cleared each year since 2000
• Logging, energy, mining, commercial plantations, settlements and subsistence farming are the main causes of deforestation in Malaysia
• Deforestation in Malaysia has led to soil erosion, loss of biodiversity, local climate change, and impacts on indigenous communities
• The Bakun Dam in Malaysia will result in 700 km2 of land being underwater, flooding large areas of forest
• Malaysia exports over 30% of the world's palm oil and is the second largest producer
• Clear felling permits are sometimes used in Malaysia to clear land, which is then later planted with palm oil