1.5.2 The Amazon Rainforest

Question 1

Fact showing the size of the Amazon rainforest

Answer 1

The Amazon is the world’s largest tropical rainforest and covers 40% of the South American landmass.

Question 2

Climate and begetation of the Amazon

Answer 2

It has a hot, very wet climate and the vegetation is very dense.

Question 3

Population of the Amazon

Answer 3

Many groups of indigenous people live in the Amazon rainforest.

Question 4

Wildlife in the Amazon

Answer 4

It’s home to up to 1 million plant species, over 500 species of mammals and over 2000 species of fish. The Amazon is also home to many endangered species.

Question 5

The importance of the water cycle on the Amazon

Answer 5

• The water cycle causes the Amazon to be very wet – there is a lot of evaporation over the Atlantic Ocean, and the wet air is blown towards the Amazon. This contributes to the Amazon’s very high rainfall.
• Warm temperatures mean that evaporation is high in the rainforest itself, which increases the amount of precipitation.
• The rainforest has a dense canopy – this means that interception is high. As a result, less water flows into rivers than might otherwise be expected, and at a slower speed.
• The water cycle affects the Amazon environment – it is populated by species that are adapted to high humidity and frequent rainfall.

Question 6

The importance of the carbon cycle on the Amazon

Answer 6

• The amazon rainforest stores lots of carbon in its vegetation and soil, so it’s a carbon sink.
• The increasing concentration of CO2 in the atmosphere has led to increased productivity in the Amazon rainforest because the vegetation is able to access more CO2 for photosynthesis – the amount of biomass has been increasing.
• As a result, the amount of CO2 sequestered by the Amazon rainforest has increased, making it an even more important carbon store.
• However, it has been suggested that although trees are growing more quickly, they’re also dying younger.
• As a result, we may not be able to rely on the Amazon rainforest to continue to be such an effective carbon sink in the future.

Question 7

Impact of climate change of the Amazon rainforest

Answer 7

Climate change can severely impact tropical rainforests. In some areas temperature is increasing and rainfall is decreasing, which leads to drought. The Amazon had severe droughts in 2005, 2010 and 2015-16.

Plants and animals living in tropical rainforests are adapted to moist conditions, so many species die in dry weather. Frequent or long periods of drought could lead to extinction of some species. Drought can also lead to forest fires, which can destroy large areas of forest, releasing lots of CO2 into the atmosphere.

Scientists predict that a 4’C temperature rise could kill 85% of the Amazon rainforest. This would result in lots of carbon being released into the atmosphere as the dead material decomposed, and less carbon dioxide being taken in from the air by trees for photosynthesis.

Question 8

Methods to limit the human impact on the Amazon

Answer 8

• Environmental Law
• Selective Logging
• Replanting
• Protection

Question 9

How can selective logging limit human impacts on the Amazon?

Answer 9

Only some trees are felled - most are left standing.

This is less damaging to the forest than felling all the trees in an area. If only a few trees are taken from each area the forest structure is kept - the canopy is still there and the soil isn’t exposed. This means the forest is able to regenerate, so the impact on the carbon and water cycle is small.

Question 10

How can replanting limit human impacts on the Amazon?

Answer 10

New trees are planted to replace the ones that are cut down. For example, a project in Peru replanted over 115 acres of forest between 2016 and 2019.

It’s important that the same type of trees are replanted that were cut down, so that the variety of trees is kept for the future and the local carbon and water cycles return to their intiial state.

Question 11

How can protection schemes limit human impacts on the Amazon?

Answer 11

Many countries have set up national parks and nature reserves to protect rainforests.

Within national parks and nature reserves, damaging activities such as logging can be monitored and prevented.

Question 12

How can environmental law limit human impacts on the Amazon?

Answer 12

Environmental laws can help protect rainforests. For example:

• Laws that ban the use of wood from forests that are not managed sustainably.
• Laws that ban excessive logging.
• Laws that control land use, e..g the Brazilian Forest Code says that landowners have to keep 50-80% of their land as forests.