WATER CYCLE SPECIFIC TO TRF

• Rates of flow and distinct stores

  • High temperatures 25-30% allow large amounts of moisture to be stored
  • Absolute and relative humidity are high
  • Strong evapotranspiration-precipitation feedback loop with half of incoming rainfall returned to the atmosphere
  • High average annual precipitation throughout the year
  • High intensity, convectional rainfall
  • High interception and evaporation
  • Rapid runoff related to intense rainfall and well drained soils
  • Significant storage of water in deep soils and aquifers
  • Water losses out of the drainage basin = river flow and clouds blown out of the region
  • Inward flux of moisture blown in from the Atlantic
• Heavy daily, convectional rainfall

  1. Trees intercept

  2. Some rain reaches the ground

  3. Trees take up water from the soil

  4. Water evaporates

  5. Back to the start
• Rates of flow


  The speed at which carbon moves through the carbon cycle
• Distinct stores


  The places where carbon is stored in the carbon cycle
• Carbon cycle in large forest trees

  • 180 tonnes of carbon per hectare above the ground
  • 40 tonnes of carbon per hectare in their roots
• Carbon cycle in rainforests


  • Major global store of carbon
• Carbon cycle in soil

  • 90-200 tonnes of carbon per hectare
• Compared to other forests


  The exchanges between the atmosphere, biosphere and soil are rapid
• Warm, humid conditions


  Lead to the speedy decomposition of dead organic matter and the quick release of CO2
• Photosynthesis rates


  Are also high
• The soils are leached and therefore store limited carbon
• The fact such inherently poor soils support the biome with the highest NPP of all terrestrial ecosystems emphasises the speed at which organic matter is broken down, mineralised and recycled
• High solar input


  1. High rates of photosynthesis

  2. Large amount of leaf litter

  3. High temperatures

  4. Rapid decomposition

  5. Carbon returned to the atmosphere
• Rock permeability


  The ability of a rock to allow fluids to flow through it
• Rock porosity


  The amount of empty space within a rock
• Amazon Basin


  • Consists of impermeable, crystalline rocks
  • Minimal water storage capacity
  • Rapid surface runoff
• Amazon Basin


  • Contains some permeable and porous limestone and sandstone
  • Store water
  • Slow runoff
• Relief


  The shape and elevation of the land surface
• Amazon Basin


  • Mostly lowlands
  • Gentle relief
  • Water moves across surface or horizontally through soil to streams and rivers
• Andes mountains


  • Steep slopes
  • Rapid runoff
• Amazon Basin


  • Widespread flooding across extensive floodplain
  • Stores water for several months
  • Slows movement into rivers
• Temperature


  The degree of hotness or coldness of the environment
• Amazon Basin


  • High temperature all year
  • High evaporation
  • Strong convection
  • High humidity
  • Intense precipitation
  • Rapid cycle between land, trees and atmosphere
• Vegetation


  • Trees are the main carbon store
  • A carbon sink of global importance
  • 60% of all the rainforest's carbon is stored in above ground biomass
  • The rest is mainly in the roots and organic matter in the soil
  • Carbon cycles between the trees, animals, soils and atmosphere
  • Photosynthesis connects the rainforest to the atmosphere store
• Temperature


  • High and intense sunlight = high NPP and rapid decomposition
  • Organic matter in soil - leaf little and other dead organic matter accumulates temporarily at the soil surface
  • Rapid decomposition by fungi releases nutrients into the soil for immediate take up by tree roots and trees release CO2 back into the atmosphere
• Mineral composition of rocks

  • Most of the basin consists of granite and metamorphites which are poor in silicate and acidic, therefore the soils that sit on top are infertile
  • Chemical weathering is very rapid
  • The soil is rich in iron, therefore has a unique red colour