The Amazon Flashcards
What area does the Amazon cover?
7,000,000km2
Which countries does the Amazon cover?
Brazil, Peru, Colombia, Venezuela, Ecuador, Bolivia etc
How much of the world’s rainforest does the Amazon make up?
More than half
How many different species are there in the Amazon?
10 million
How much of the world’s CO2 does the Amazon absorb?
35%
How much of the world’s Oxygen does the Amazon produce?
20%
What is the average rainfall per year?
3000mm
Why does up to half of rainfall never make it to the ground?
It is intercepted by the forest canopy and re-evaporated into the atmosphere
What happens to water intercepted by the canopy?
It drips to the ground from leaves (drip tips) or flows down the tree via stemflow
What percentage of freshwater entering the oceans each day comes from the Amazon river?
15%
What can deforestation increase?
- Rainfall downwind of the area.
- Soil erosion
- Faster surface runoff
- Loss of habitats
What are the main drivers of change to the Amazon water cycle?
Deforestation, land use changes, climate change
How can land use change affect the water cycle?
Cutting down trees for farming means water can fall straight to the ground, causing soil erosion and runoff
Why does deforestation reduce rainfall in the area?
Because the water cycle is disrupted as evapotranspiration does not occur and less water is stored in plants, and more in soil
Why is water less likely to evaporate from soils?
Why is water less likely to evaporate from soils?
Because it forms a thin layer on a leaf so can evaporate quickly with less energy, but when it reaches the soil it soaks in
What does a decrease in evaporation lead to?
Local warming and droughts
What do rainforests act as?
Carbon sinks
How do plants store Carbon?
As sugars, in the form of starch in their leaves
How does deforestation by burning affect the carbon cycle?
No respiration by trees, no photosynthesis, no new biomass, less decay
What human factors can affect carbon cycle stores and transfers?
Industry and burning of fossil fuels, burning of forest
How do warmer oceans affect carbon stores?
Warmer oceans cannot hold as much CO2 so absorb less carbon
What physical factors can affect carbon cycle stores and transfers?
Tress and plants, temperature changes, type and number of animals in an area
How can extreme events of climate change alter vegetation?
Heatwaves, drought and storms can lead to vegetation deaths and fires
