AMAZON RAINFOREST Flashcards
(36 cards)
size of amazon
worlds largest tropical rainforest
covers 40% of SAm land mas
covers 68% of brazil
conditions of amazon
very hot and wet
vegetation is very dense
what lives there
many indigenous people
1 million plant species
500 species of mammals
2000 species of fish
- particularly endangered species of them all
what causes the amazon to be so wet
evaporation from the Atlantic ocean being blown over
what causes high evapotranspiration
warm temperatures
what causes high interception rates. what’s does this mean for the water cycle
dense canopy
less water flows - flows more slowly into the river
what are the species adapted towards
the high humidity
what dos the amazon store, what does this make it
carbon - in vegetation and soil
carbon sink
how much of the amazon is considered a carbon source
1/5
negative feedback loop - CO2 and plants
increase CO2
increased productivity - plants absorb more CO2 for photosynthesis
biomass increases
how much CO2 absorbed in 1990s vs 2015
1990 - 2 billion tonnes
2015 - 1 billion tonnes
how much of the original land has been lost to deforestation
17%
what % of deforestation is associated with farming
90% - cattle and agriculture
- arable and pastoral
what impact does deforestation - farming have on the water cycle
no tree canopy to intercept rainfall - more water reaches ground surface
fills up water table
becomes runoff
increase flood risk
decreased river discharge
what does deforestation do to evapotranspiration.
what does this mean - neg
reduces it
less water in the atmosphere, fewer clouds and rainfall is reduced. 1/3 of the areas rainfall is recycled - could lead to drought
what does reduced evapotranspiration mean after deforestation.
- change weather patterns locally
- affects carbon cycle
what does reduced evapotranspiration mean after deforestation - change weather patterns locally
become wetter/windier at local scale
cleared areas warm up faster and warm air rises, creating low pressure - drawing in moist air from surroundings
vegetation breezes create clouds and rain
what does reduced evapotranspiration mean after deforestation - affects carbon cycle
w/o roots to hold soil, heavy rain washes away top layer of soil
= transfers carbon from soil –> hydrosphere
human activities that affect carbon and water cycles
deforestation
climate change
what does fewer trees mean
less photosynthesis
less CO2 taken up
global warming increased
how many tonnes of carbon per hectare do tropical rainforests hold
500
how many tonnes of carbon per hectare does farmland hold
5 tonnes
100 times less than tropical rainforests
more CO2 left in the atmosphere
what has drought been experienced
what years has this happened
temp increasing
rainfall decreasing
2005, 2010, 2015-16
what does drought encourage
forest fires
- releases more carbon into atmosphere, increased GHE
