Amazonia

• Amazon rainforest = tropical rainforest covering 40% of South America
• WWF: 34 mn ppl live in Amazonia, inc. 385 indigenous groups who depend on its services and resources
• Over 20% of Amazon = destroyed @ accelerating rate in last 50 years due to:

  • cattle ranching
  • large scale commercial agriculture for biofuels and soya beans
  • development of towns and roads
  • Illegal + legal logging

  NB: Brazilian gov. encourages such actions
• Amazon contains 60% of world's rainforests and so environmental impact is prevalent and highly significant
• Trees act as 'green lungs' by removing CO2 as they photosynthesize and act as carbon sinks
• Destruction of forest reduces carbon sink capacity and hence adds to global greenhouse emissions, esp. in times of drought
• In forest: 75% of intercepted water is returned by EVT to atm which reduces to approx. 25% when forest is cleared so drier climate causes desiccation and further forest degradation
• ENSO cycle = significant occurrence of droughts in Amazonia which exacerbates forest fires and furthers destruction
• Water cycle = increased run off to drainage basin system so exacerbated possibility of severe flooding, mudslides and aquifer depletion as less water infiltrates to recharge them
• Overland flow increases soil erosion and degradation as nutrients are ' washed away '