Amazon Rainforest Flashcards
Describe the size of the Amazon.
Largest and most diverse rainforest in the world
How much land does it cover?
6 million square kilometers
How many trees are there
300 billion
Average rainfall
2,300mm per year but can reach up to 6,000mm
Average temperature
28°c
Amazon river discharge
209,000 cumecs per second
What helped form the amazon
Hadley cells meet equator forming Inter Tropical Convergence Zone (ITCZ). ITCZ as well as lots of evapotranspiration creates conditions needed for a tropical rainforest
How much carbon does the Amazon store
Stores 90-140 billion tons of carbon - 20% of worlds carbon
What is net carbon change for the Amazon
Absorbs 1-3 billion tons of carbon per year. Overall gain makes it a carbon sink.
What percentage of water remains in a loop of evapotranspiration and precipitation?
70%
How much deforestation is from commercial farming?
70%
What are reasons for deforestation
Cattle ranching, logging, farming, mining, housing
How much of the Amazon will have been cut down by 2030 if current rates continue?
27%
How does deforestation of the amazon impact climate
Reduced humidity and cloud cover from reduced evapotranspiration
How does deforestation of the amazon impact soil
Rain goes straight to soil causing compaction, increased surface run off and therefore flood risk as well as washing away leaf litter causing reduced soil nutrients
How does flooding pose a threat to the Amazon?
Can destroy freshwater ecosystems and water sources for Amazonian people
How does deforestation of the amazon impact cloud cover
Slash and burn releases aerosols which can cause too many condensation nuclei leading to too many small water droplets and therefore reduced rain
Trees release natural aerosols however after they are cut down, these are no longer released meaning there is not enough condensation nuclei for clouds to form and therefore reduced rainfall.
Why is slash and burn so environmentally damaging?
Cutting down of trees releases carbon into the atmosphere but the burning of felled trees causes the remaining carbon to also be released into the atmosphere instead of being absorbed into the soil.
What is the flying river?
Prevailing winds causes large amounts of water vapour to move above the Amazon, creating a “flying river”
Positive feedback loop of the flying river
Deforestation causes a reduction in evapotranspiration, flying river becomes smaller, less precipitation from the flying river, can cause trees to die from reduced rain, reduces evapotranspiration
How does deforestation affect flood risk in the Amazon
Increased surface runoff and reduced interception of water by vegetation due to deforestation causes more water to enter rivers and faster, increasing flood risk.
Impacts of human activity
Land use changes causes large amounts of deforestation, often by slash and burn, releasing lots of carbon into the atmosphere.
What is causing stress to the Amazon?
Directly: deforestation, exploitation of resources, agriculture
Indirectly: enhanced greenhouse effect causing global warming and climate change
How has the Amazon’s carbon storage capacity changed?
Decreased from 2 billion tons per year in 1990 to 1 billion in 2015
