The amazon Flashcards
(19 cards)
Basic facts about the amazon
-Largest tropical rainforest on Earth
-Covers 40% of South America
-Spread over 9 countries
-Home to 34 million people
-Covers 2.1 million square miles
-Home to 20% of species on Earth
How does the amazon link with the carbon cycle ?
-Dead amazonian trees (20% of above ground biomass) emit around 1.9 billion tons of carbon
-Absorbs 2.2 billion tons in untouched state (acting as a sink)
-over the past decade above ground biomass has declined by a third (less efficient at trapping carbon)
How does the amazon link with the water cycle ?
-Links lithosphere, atmosphere,biosphere
-Rio Negro is the 2nd largest river in the world (100m deep, 14km wide)
-Average discharge of water into the Atlantic is 175,000 m3 per second from Amazon River
-Average rainfall across basin yearly is 2300mm
-only 1/3 of rainfall reaches Atlantic (interception, evaporation, transpiration, clouds)
-Water cycle has global effects as moisture that’s created travels globally (50-80% of moisture remains in the ecosystems water cycle)Chn
What is causing changes to the water and carbon cycle ?
-Deforestation
-Logging
-Road building
-Mineral extraction
-Energy development
-Settlement/population growth
What are the impacts of these changes on the atmosphere ?
-Deforestation causes changes in energy and water balance
-Pasture/crop lands have higher albedo, decreased evapotranspiration and interception compared to forests they replace (impacts atmospheric circulation)
Describe the Amazon rainforest and its location
-The Amazon covers 40% of South America.
-Brazil, Bolivia, Peru, Ecuador, Colombia
-Sits within the Amazon River Basin.
-Home to 10 million species of insects.
-Home to 20 million people.
-Covers 5.3 million sq km
How does the carbon cycle link with the Amazon ?
-Acts as a carbon sink when untouched (absorbs 2.2 billion tonnes)
-Stores between 80-120 billion tonnes of carbon
-Approx 100 Pg C above ground biomass (huge store of carbon)
-Amazon holds 17% of the global terrestrial vegetation carbon stock
-Dead Amazonian trees emit 1.9 billion tonnes of carbon
What are the changes to the water and carbon cycle in relation to Agriculture ?
-To grow crops (soya, palm oil) or for pasture land (cattle grazing)
-Pasture land is approx 9 degrees warmer than forest land
-Converting forest to pasture land leads to less precipitation as deeper forests pump more soil moisture to the surface
Water cycle: Less trees = less evapotranspiration → less rainfall, more runoff, higher flood risk.
Carbon cycle: Trees cut/burned = more CO₂ released, less carbon absorbed → worsens climate change.
What are the changes to the water and carbon cycle in relation to logging ?
-Cutting of trees for sale of timber or pulp (wood used to build homes or make paper)
-Logging can be selective or clearing (specific trees or all)
-Slash and burn
-Water Cycle:
Reduced interception and transpiration due to tree removal
Less atmospheric moisture and lower regional rainfall
Increased surface runoff → more flooding and soil erosion
-Carbon Cycle:
Decreased carbon sequestration as trees are removed
More CO₂ released from decaying or burned vegetation
Contributes to enhanced greenhouse effect and climate change
What are the changes to the water and carbon cycle in relation to road building ?
-Less interception
-Impermeable surface
-Increases runoff
-More pollution from vehicles using it (further access deeper into forest)
-Trans Amazonian Highway has opened up large areas of Amazon ( allows development)
-Unusable in wet months
-Removal of vegetation decreases carbon sequestration
What are the changes in water and carbon cycle in relation to mineral extraction ?
-Water Cycle:
Deforestation reduces canopy cover → less interception and evapotranspiration.
Increased surface runoff and flood risk.
Disruption to local rainfall patterns.
-Carbon Cycle:
Loss of trees reduces carbon storage capacity.
Burning and decomposition release CO₂.
Disturbed soils release stored carbon.
Net increase in atmospheric CO₂ → contributes to climate change.
What are changes in water and carbon cycle in relation to energy development ?
Water Cycle: Dams flood large forest areas, reducing evapotranspiration and altering regional rainfall patterns. Reservoirs increase surface water, leading to more evaporation and possible localised humidity changes.
Carbon Cycle: Flooded vegetation decomposes anaerobically, releasing methane, a potent greenhouse gas. Deforestation for infrastructure reduces carbon sequestration and increases CO₂ emissions from biomass decay and transport activity.
-Belo monte d am generates 11,000 Mw of power anually
What are changes in the water and carbon cycle in relation to settlement and population growth ?
Water Cycle: Less vegetation reduces evapotranspiration, leading to lower humidity, reduced rainfall, and increased surface runoff, raising the risk of flooding and erosion.
Carbon Cycle: Trees are major carbon sinks. Their removal decreases carbon sequestration and increases CO₂ emissions from biomass burning and decomposition, contributing to climate change.
-2000-2010 23% pop increase
-WWF estimates 27% of Amazon biome will be lost by 2030 if current rates maintain
Describe the impacts of climate change to the Amazon
-30% of anthropogenic carbon emissions come from the burning of forests
-Higher temps will impact temp dependent species e.g. fish
-Reduced rainfall and increased temps reduce the quantity of suitable habitats during dry and warmer months
-Less rainfall in dry months could affect freshwater systems
-Change in nutrient input as result of less rainfall
-More variable climate and more extreme events
-Flooding as a result of sea-level rise, could increase 5mm per year
Describe changes in the atmosphere in the atmosphere
-Forest land has been replaced with pasture lad and croplands so evapotranspiration rate has decreased
-Contributed 50km3 per year of evapotranspiration to the atmosphere, in 2009 only contributed 40km3
-Deforestation since 1970’s caused an 18 day delay in onset of rainy season
What are the changes to the soils in the Amazon ?
-Removal of trees deprives forest of portions of its canopy which blocks sunrays and holds heat in at night resulting in extreme temp changes which are harmful to plants and animals
-Without tree cover the soil quickly dries out causing carbon to escape the top layer of soil which holds 52% of carbon stored within soil
What are changes to rivers in the Amazon ?
-Trees return water vapour, leading to precipitation
-Without trees an area can suffer more droughts
-Increased soil erosion and weathering due to no interception
-Flash floods, less interception and absorption by forest cover lowers lag time
-Increased risk of wildfires
-More soil and silt washed into rivers
-Disrupt water supplies to Brazil
How is climate change being mitigated against in the Amazon ?
-National and international agreements
-TARAPATO process to help achieve harmonous forest development
-Amazon cooperation treaty organisation (ACTO) to promote harmonious development
-Latin American Technical cooperation network on watershed management
-Creation of natural parks and forest reserves
-Forest biofuel production could compete with ethanol production from sugar can by 2030
-Reforestation much of Brazils industrial timber comes from planted forests which make up 2% of forest areas
-Enrichment of degraded forests using native species
Give an example of a feedback within the Amazon
Increased deforestation and climate change in the Amazon
Soils and environment become drier
Results in more wildfires
Increases atmospheric aerosol loads produced by fires
Decrease in rain droplet size, increase in cloud height and lifetime inhibit rainfall, particularly in the dry season
