Fichas
tropical rainforest - Amazon
Fichas del conjunto (37)
- 1where is the Amazon Rainforest ?south America - it spreads across 9 countries
(Bolivia, Brazil, Peru, Ecuador, Colombia, Venezuela, Guyana, Suriname, french Guiana) - 2the amazon basin is the world's largest rainforest and one of the most biodiverse, its 300 billion trees and 15,000 species store how much of all the carbon in the planets biomass ?1/5
- 3today the amazon rainforest covers around how many km2 and is spread across 9 countries ?5.5 million km2
- 4CARBON: the Amazon is estimated to store between 80 - 120 billion tons of carbon, along with other tropical rainforests around the globe it forms a carbon sink of what ?1-3 GtC/year
- 5CARBON: studies have shown that these forests have been increasing in above-ground biomass per year and that the rising productivity of tropical forests is due to what ?sequestering of increased CO2 concentrations in the atmosphere
- 6CARBON: the increase in above ground biomass, the rising productivity and the sequestering of increased CO2 = negative feedback seems to have done what ?offset rising atmospheric levels of CO2
- 7CARBON: a study completed in 2015 revealed that the Amazon forest is loosing its capacity to absorb CO2 from the atmosphere - the net uptake has now what ?halved from the peak of 2 billion in 1990s
- 8CARBON: it appears that for the amazon basin an increase in atmospheric CO2 has lead to what ?led to a growth spurt for the Amazon's trees, the growth stimulation feeds through the system causing trees to live faster and so die younger - led to a surge in the rate of trees dying across this amazon
- 9WATER: the average discharge of water into the Atlantic ocean by the Amazon is approximately how many m3/s ?175,000
- 10WATER: what tributary of the Amazon is the second largest river in the world in terms of water flow ? - it is 100m deep and 14 km wide near its mouth in BrazilRio Negro
- 11WATER: average rainfall across the amazon basin is approximately how many mm annually ?2,300 mm
- 12WATER: in some areas of the northwest portion of the amazon basin it can exceed up to what?6,000 mm
- 13WATER: up to half of this rainfall never reach the ground - why ?it is intercepted by the forest canopy and re-evaporated from the ground and rivers or is released into the atmosphere by transpiration from leaves
- 14DRIVERS OF CHANGE : between 2000 and 2007 in the Brazilian Amazon what was happening at a rate of 19,368 km2deforestation
- 15DRIVERS OF CHANGE : brazil is the worlds fourth largest what ?climate polluter
- 16DRIVERS OF CHANGE : the removal of forest was done using slash and burn techniques which does what ?- reduces the retention of humidity in the soil's top layer down to a depth of 1m
- facilitates sudden evaporation of water previously retained in the forest canopy
- increases albedo and temperature
- reduces porosity of soil causing faster rainfall drainage, erosion and silting of rivers and lakes - 17DRIVERS OF CHANGE : any moisture that evaporates from deforested areas forms what ?shallow cumulous clouds which usually do not produce rain
- 18DRIVERS OF CHANGE : if destroyed what will be released in the atmosphere ?the vast carbon store
- 19DRIVERS OF CHANGE : there are a range of differences between tropical rainforest and the pasture land it is generally replaced with - what are these ?- forests absorb approx 11 % more solar radiation
- average temperature in the rainforest is approx 24 degrees in pastures its 33 degrees
- the moisture content in the upper 1 metre of pasture soil is about 15% less than under nearby forest
- deeper forest roots can pump more moisture to the surface producing 20-30% more air humidity - 20CLIMATE CHANGE : studies investigating all tropical rainforest regions predict that a by the year 2050, temperatures in the Amazon will increase by what ?2-3 degrees
- 21CLIMATE CHANGE : there has also been evidence of more frequent and increased extremes in temperature - amazonia experienced falling amounts of rainfall between when ?1920s - 70s
- 22VEGETATION CHANGE : there has been a massive net loss of forests in the Amazon Basin about how many hectares per year between 2000 - 2010 ?3.6 million hectares
- 23VEGETATION CHANGE : a significant amount of the vegetation loss is caused by deliberate deforestation, a significant amount has been a result of what ?climate change
- 24VEGETATION CHANGE : some species are limited by the tolerance to temperature change, drought and seasonality - climate change can affect species sustainability how ?directly altering the conditions needed to grow and survive
- 25VEGETATION CHANGE : what in recent years may also be a role in killing millions of trees although the tree mortality increases began well before one of these things in 2005 ?droughts and unusually high temperatures
- 26VEGETATION CHANGE : a 2009 study concluded that a 2 degrees temperature rise above pre-industrial levels would see what % of the amazon die off within 1000 years20-40%
- 27SOIL: Amazonian soils contain from 4-9 kg of carbon in the upper 50cm of the soil layer while pasturelands contain what ?1 kg/m2
- 28SOIL: when forests are cleared and burned, 30-60% of the carbon is lost to the atmosphere; unburned vegetation decays and is lost within 10 years - what will also die off ?the soil fungi and bacteria that used to recycle dead vegetation die off
- 29SOIL: when forest clearance first occurs, the soils are what ?exposed to the heavy tropical rainfall
- 30SOIL: this rapidly washes away the topsoil and attacks the deep weathered layer below - what happens to most of the soil ?most of the soil is washed into rivers
- 31RIVERS: changes in total precipitation, extreme rainfall events and seasonality may do what ?- lead to an overall reduction in river discharge
- cause an increase in silt washed into the rivers, which could disrupt river transport routes
- lead to flash flooding
- destroy freshwater ecosystems
- destroy water supply which fulfils the needs of amazonian peoples - 32RIVERS: warming water temperatures may do what ?- kill of temperature dependent species
- change the biodiversity of the river system by introducing new species and killing others
- reduce water-dissolved oxygen concentrations - 33MITIGATION: the creation of national parks and forest reserves - give an example ?- the Tumucumaque National parks (3.84 mill hectares) or para rainforest reserve (15mill hectares)
- 34MITIGATION: forest biofuel production could compete with what ?ethanol production from sugar cane by 2030
- 35MITIGATION: reforestation - much of Brazil's industrial timber comes from planted forests which makes up how much of the forest area ?2 %
- 36MITIGATION: enrichment of degraded forests using what?native species
- 37MITIGATION: national and international agreements such as ?- The Latin American Technical Cooperation Network on Watershed Management
- The TARAPOTO process to help achieve harmonious forest development
- Amazon Cooperation Treaty Organisation to promote harmonious development
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- (water and carbon) geography case studies / examples Fichas sobre tropical rainforest - Amazon, creado por niamh bergin el 22/04/2018.
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- niamh bergin
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