The Amazon Rainforest

Question 1

General info?

Answer 1

• Worlds largest tropical rainforest that covers over 40% of South America
• Population of 47 million people including 2 million indigenous
• Home to over 1 million plant species, 500 animal species and 2000 fish species including several endangered species such as the black caiman

Question 2

Outline processes of the water cycle in the Amazon.

Answer 2

• high rates of Evaporation over the Atlantic Ocean means water vapour is blown towards the Amazon which causes high volumes of precipitation
• warm temperatures over the Amazon itself causes high rates of evapotranspiration which further increases precipitation
• High rates of interception due to dense canopy which means less surface run off to rivers which reduces flooding

Question 3

Water cycle statistics?

Answer 3

• 25% of precipitation is immediately evaporated due to high avg temps of 28 degrees
• 75% is intercepted, of which half is used by plants and half is infiltrated
• Extreme droughts occurred in 2005, 2010, 2015-2016
  Link: The Amazon River basin absorbs 1.2 billion tonnes of CO2 every year

Question 4

Outline processes in the carbon cycle in the Amazon.

Answer 4

• The Amazon is a carbon sink as it stores large volumes of carbon in vegetation and soil
• Increased atmospheric CO2 has increased plant productivity so more photosynthesis and plant growth
• Trees are growing faster and dying younger as a result
• Decomposition and respiration release CO2 as bacteria in the soil decompose dead organic matter

Question 5

Carbon cycle statistics?

Answer 5

• The Amazon stores 150-200 billion tonnes of Carbon
• Absorbs 25% of all CO2 absorbed by land on Earth

Question 6

Outline processes and effects of human activity in the Amazon?

Answer 6

• deforestation occurs due to logging, agriculture and construction
• causes less interception and more surface run off as soil becomes saturated which causes flooding
• reduced evapotranspiration so less precipitation and more droughts
• tree roots can’t hold soil together so rain washes away top nutrient rich Mayer (leeching)
• less leaf litter so humus isn’t formed so soil is less fertile so fewer plants can regrow and absorbed CO2
• More atmospheric CO2 as deforested trees release CO2 and can’t further absorb any

Question 7

Deforestation statistics?

Answer 7

• Approximately 17% of the rainforest has been lost due to deforestation
• during combustion, trees release up to 60% of stored carbon immediately
• 1.98 million hectares cleared in 2022 which is a 21% increase from 2021
• 62% of land is cleared for agricultural purposes
• Deforestation is responsible for 75% of Brazils Carbon emissions
• over 90% of Amazon deforestation is illegal
• after Bolsonaro was elected in 2019 rates increased by over 60% as he encouraged deforestation for economic growth
• In the first 6 months of Lulas presidency deforestation decreased by 35%
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Question 8

Outline the impacts of climate change.

Answer 8

• temperatures increase, rainfall decreases which causes droughts
• droughts can cause wildfires which emit CO2 (44.2 million acres burned in 2024)
• plant and animal species are adapted to humid warm conditions so some face extinction

Question 9

Climate change stats?

Answer 9

• 2005, 2010, 2015-16 droughts
• 44.2 million acres burned via wildfires in 2024
• combustion released 1.5 billion tonnes and vegetation absorbs 0.5 billion tonnes (both annually) leaving an excess of 1 billion tonnes of CO2 so Amazon converting form sink to source
• A temperature rise of 4 degrees could kill 85% of the rainforest

Question 10

Mitigation strategies and stats?

Answer 10

• national parks such as the Central Amazon Conservation Complex protects 49,000 km 2 and was established in 2003
• aforestation schemes e.g. scheme in Peru replanted 115 acres between 2016 and 2019
• laws and legislation e.g. Brazilian forest code states land owners must keep up to 80% of their land as forest