1.1- The Amazon

Question 1

Drainage Basins

Answer 1

Regional/local open systems, with a varying amount of water stored. The catchment area is determined by the topography of the land.

Question 2

The Amazon, Brazil

Answer 2

• The largest river drainage basin.
• Represents 20% of global freshwater at the ocean.
• Precipitation is extremely high given it’s at the equator due to convectional rainfall and high evaporation.

Question 3

Amazon Drainage Basin

Answer 3

Interception and evapo-transpiration is extremely high due to dense vegetation canopy cover, making it a semi-closed system. Precipitation is high though so a lot of water reaches the ground.

Question 4

Effects Of Heavy Rainfall On The Amazon

Answer 4

• High temperatures and moisture have chemically weathered the bedrock.
• Soil is thin and low on nutrients over a layer of clay causing low permeability and high surface-runoff.
• Carbonate rocks have allowed for some percolation and therefore increased groundwater storage.

Question 5

Overall Effects Of Increased Precipitation On Drainage Basins

Answer 5

Annual river runoff increases
Soil moisture increases
Evaporation increases
Evapotranspiration increases
The above cause increased precipitation

Question 6

Overall Effects Of Decreased Precipitation On Drainage Basins