Amazon Rainforest

• where is the Amazon rainforest located?

  South America, and occupies 6 million Km2

  
• what % is the Amazon rainforest located in Brazil?

  70%
• what type of trees dominate the rainforest ?

  tall,evergreen, hardwood trees
• The rain forest water cycle

  High average annual temperatures ( 25- 30)

  Small seasonal variation in temperature

  High average annual rainfall (2000mm) with no dry season.

  
• what does cloud cover ensure?

  cloud cover ensures that maximum temperatures do not reach the extremes of subtropical desert climates. intense insolation results in high temperatures.
• between what %s of percipitation in Amazonia is recycled by evapotranspiration?

  between 50 & 60%
• what are the six flows and stores in the water cycle in Amazon rainforest?

  1. Precipitation

  2.Evapotranspiration

  3.Run-off

  4.Atmopshere

  5.Soil/groundwater

  6. Vegetation
• what are the characteristics of rainfall in the Amazon rainforest?

  Rainfall evenly distributed throughout the year, though some short dry seasons. High intensity, convectional rainfall. interception by forest trees is high ( 10%). Intercepted rainfall accounts for 20-25 % of all evaporation.
• What are the characteristics of evapotranspiration in the Amazon Rainforest?


  High rates of evaporation and transpiration due to high temperatures, abundant moisture and dense vegetation. strong evapotranspiration - precipitation feedback loops sustain high rainfall totals. Half of incoming rainfall is returned to atmosphere by et. Most evaporation is from intercepted moisture from leaf surfaces. moisture lost in transpiration is derived from the soil via tree roots.
• Net primary productivity


  is high, averaging 2500 grams/m2/year and the biomass is between 400 and 700 tonnes/ha
• how much carbon does the typical large forest tree hold?

  180 tonnes above ground

  40 tonnes in roots
• how much carbon can soil store ?

  between 90 and 200 tonnes
• How much carbon is absorbed in the Amazon rainforest per year?

  2.4 billion tonnes a year
• forest ecosystems


  compared to normal forest ecosystems, exchanges of carbon between the atmosphere, biosphere and soil are rapid.
• what do warm,humid conditions ensure?

  ensures speedy decomposition of dead organic matter and the quick release of CO2. meanwhile, rates of carbon fixation through photosynthesis is high.
• Amazons leached and acidic soils contain only limited......

  carbon and nutrient stores.
• What are the physical factors that affect flows an stores of water?

  Geology, relief and temperature
• What effect does geology have on the hydrograph?

  impermeable catchments have minimal water storage capacity resulting in rapid run-off. permeable and porous rocks such as limestone and sandstone store rainwater and slow run-off.
• What effect does relief ( slopes ) have on the hydrograph?

  most of amazon is lowland. in areas of gentle relief water moves across the surface (overland flow) or horizontally through the soil (through flow) to streams and rivers. west - Andes create steep catchments with rapid run-off. widespread inundation (flooding) across extensive floodplains occurs annually, storing water for several months and slowing its movement into rivers.
• What effect does temperature have on the hydrograph?

  hight temps create high rates of evapotranspiration. convection is strong leading to high atmospheric humidity. the development of thunderstorm clouds and intense precipitation. water is cycled continually between the land surface, forest trees and the atmosphere by evaporation, transpiration and precipitation.
• How much carbon does the Amazon rainforest release?

  1.7 billion tonnes a year
• where is 60% of carbon stored?

  above ground, in the biomass of tree stems, branches and leaves. the remainder is below, mainly as roots and soil organic matter.
• what connects the rainforest to the atmosphere carbon store?

  Photosynthesis
• leaf litter and dead organic matter ....


  accumulates temporarily at the soil surface and within rainforest soils.
• what do high temperatures and humid conditions promote?

  promote rapid decomposition of organic litter by bacteria, fungi and other soil organisms.
• what does decomposition release?

  releases nutrients into the soil for immediate uptake by the roots and emits Co2, which is returned into the atmosphere.
• what geology dominates the Amazon basin?

  ancient igneous and metamorphic rocks
• what geology can be found in the west of the basin, close to the Andes?

  outcrops of limestone occur
• What human factor that affects stores and flow of water, averaged around 17,500 km2 between 1970 and 2013?

  Deforestation

  
• how much of the rainforest has been destroyed or degraded?

  almost 1/5 since 1970
• in 2014, what river did the devastating floods occur ?

  Madeira River
• how many people died in the flood and how many people where evacuated?

  60 people died

  68,000 families evacuated
• what diseases where a result of this flood?

  cholera and leptospirosis