amazon rainforest case study

Question 1

key facts

Answer 1

amazon covers 40% of South America
very hot and wet climate - 2000mm rainfall annually, evenly distributed seasonally
home to many endangered species

Question 2

water cycle

Answer 2

high rates of evaporation over the Atlantic Ocean, wind blows wet air over the amazon which leads to high rates of precipitation (2000mm per year)
warm temperatures induce high rates of evaporation = increased precipitation
dense canopy increases interception, less water flows overland into rivers

Question 3

carbon cycle

Answer 3

amazon is a huge carbon store due to its biosphere and pedosphere
increased productivity of photosynthesis, increases concentration of CO2 in atmosphere
CO2 sequestered by amazon is increasing
however, trees are being cut down/dying which suggests that amazon may not be very reliant in future

Question 4

deforestation impact on water cycle

Answer 4

• no tree canopy, less interception, higher rates of surface runoff, increased flooding
• reduced evapotranspiration, less water vapour in atmosphere, fewer clouds, increased risk of drought

Question 5

deforestation impact on carbon cycle

Answer 5

• no roots to hold soil together causes rainfall to wash away nutrient rich layer of topsoil, transfers carbon from pedosphere to atmosphere
• less trees absorb less CO2, reduces effectiveness as a carbon store, increased carbon in atmosphere exacerbates positive feedback effect
• slash and burn practices produce carbon

Question 6

climate change

Answer 6

temperature increasing, rainfall decreasing = increases risk of severe drought
= increased rate of forest fires, emit huge amounts of CO2
scientists state a 4 degree rise in temperatures would kill 85% of the amazon

Question 7

mitigation: selective logging

Answer 7

only some trees are deforested, majority of trees are protected
- protects soil structure
- provides canopy

Question 8

mitigation: replanting

Answer 8

replanting = trees are replanted to replace trees that are deforested
- Peru replanted 115 acres between 2016-2019

Question 9

mitigation: environmental laws

Answer 9

environmental laws = laws that ban unsustainable use of trees
- ban excess logging
- controlling land use = Brazil state that landowners must keep 50-80% land as forest