Amazon Basin

• NPP is 2,500 g/m2 = so quick that it absorbs 1/4 of all carbon dioxide released by humans
• 200-300 tonnes of carbon stored per hectare
• Mean NPP = Rainforest - 2,200 g/m2, Deciduous rainforest - 1,200 g/m2
• Emergent tress called “Kapok” which can grow up to 50 metres high
• Autotrophic respiration (vegetation) + Heterotrophic respiration (decomposers) = release carbon
• Between 50-60% of precipitation in Amazonia is recycled by evapotranspiration
• High average rainfall of above 2000mm with no dry season
• Convectional rainfall peaks at 21:00 and is driest at 15:00 (highest level of incidence at midday)
• Intercepted rainfall accounts for 20-25% of all evaporation
• Brazilian shield, Guyana Shield & Andean belt = indigenous rocks - impermeable + low porosity = can’t store water
• Middle part of basin in Cenozoic rock (sedimentary rock) = permable + high porosity = stores water = less run-off
• Steep slopes at the Andean mountains and Guyana highlands = high rates of run-off
• 6 months of constant rainfall accumulating trillions of gallons of water
• River can rise up to 10m during the wet season
• The last 2 decades of wet season have had rainfall figures since the records began