tropical rainforest

Question 1

background on the Amazon Rainforest

Answer 1

6 million km² spanning 9 countries in south america
home to 34 million people
most biodiverse biome storing 1/5 of all carbon on Earth

Question 2

links to the water cycle

> any key stats peehaps?

Answer 2

average precipitation 2300mm
rainfall is RAPIDLY intercepted by the vegetation
About 70% of water remains in this closed loop of evapotranspiration and precipitation, with only about 30% reaching the sea

Question 3

link to the carbon cycle/ effect of climate change on this complex ecosystem

Answer 3

important carbon store of 1/5 equating to 90-140 bilion tonnes of carbon
NEGATIVE FEEDBACK: more ^productive^ due to higher levels of co2. results in more biomass so more sequestering
POSITIVE FEEDBACK: trees can die younger (dieback) and create destabilsation of the water cycle in the area

Question 4

what is the climate like in the Amazon?

Answer 4

hot and wet

Question 5

effects of deforestation (general)

Answer 5

rates of interception lowers. little evapotranspiration.
runoff increases as does risk of flooding (overland flow)
reduced precipitation levels as no clouds form directly affecting the climate
soils/topsoil exposed to the sun increasing risk of soil erosion
the biodiversity of area greatly reduces

Question 6

name ways in which water can return to the atmosphere?

Answer 6

evaporation from ground
evaporation from rivers
evapotranspiration of leaves

Question 7

why are rainforest workers deforesting the amazon?

Answer 7

● make land for commercial farming of palm oil, rice, sugar and coffee. This contributes to 70% of all deforestation in Brazil
● increased migration out of urban areas ^encouraged by government incentives^
● provide wood for furniture by logging
● building dams to provide HEP however
in Balbina it burst and flooded 2300km²

Question 8

evaluative points

> a look towards the future

Answer 8

continued deforstation will greatly affect the preciptation levels and s negatively impact existing agriculture.
however demand for commodities is increasing so the future is uncertain

Question 9

how does deforestation affect water transfer

Answer 9

less infiltration and more overland flow and surface runoff
leaching of nutrients important for the biome
less shelter so rapid evaporation forming shallow cumulus clouds which don’t cause rain
soils dry up making ‘burnt’ areas susceptible to flooding

Question 10

how much of the amazon is gone?

Answer 10

20% due to unsustainable development