Amazon rainforst

Question 1

amazon forest key points

Answer 1

• largest tropical rainforest on earth
• sit in amazon river basin
• covers 40% of south america continent
• cover countries like Brazil, Ecuador, Peru, Colombia, Bolivia etc
• home to 20 million ppl and almost 20% of species on earth
• currently lost 20% of it due to deforestation etc
• hot and wet climate = increases evaporation rate and cloud formation etc , dense vegetation
• diverse biodiversity
• dense canopy (interception etc) = decreases water in rivers —> 75% intercepted

Question 2

carbon

Answer 2

• amazon = carbon sinks and stop (especially when untouched —> efficiency in trapping carbon down by 1/3 since 1990s) —> helped reduce global warming
• amazon holds 17% of global terrestrial vegetation carbon
• 1% amazon tree species store half the carbon
• dead amazon trees emitting less carbon annually than the rainforest absorbs

Question 3

water

Answer 3

• amazon links lithosphere , atmosphere, biosphere
• amazon river discharge = around 1/5th of total discharge from all rivers to the ocean
• average rainfall = 2300mm (some areas exceeding 6000mm
• 1/3 rainfall discharged to Atlantic = global effects —> influenced rainfall patterns in Texas, China, Europe etc
• deforestation = less water in atmosphere= less rainfall and droughts

Question 4

causes of deforestation in Amazon?

Answer 4

• agriculture- land clear for crops e.g. palm oil/for cattle grazing (65% of deforestation)
• logging- trees cut for timber (homes and furniture)/ pulp paper —> selective logging = targets high value wood , Clear-cutting = cutting all trees in area
• road building- Trans Amazonian highway (1972)= makes forest more accessible and vulnerable
• mineral extraction- mining (large scale) for gold etc
• energy development - hydroelectric power dams= displaced ppl (indigenous communities) , flood land , alter water cycles and trap sediment and disrupts ecosystems —> 150 dams planned e.g. BeloMonte Brazil
• settlement and population growth- migrants = create settlements , more housing and infrastructure

Question 5

deforestation trends

Answer 5

• WWF= estimate 27% of Amazon may be deforested by 2030

Question 6

impacts of deforestation

Answer 6

• changes energy and water balance of amazon
• less evapotrans.= reduces moisture (less clouds) and affects rainfall etc
• rainy seasons delayed (e.g. Brazil by 18 days since 1970s)
• wildfires due to deforestation, droughts etc —> creates positive feedback loop —> droughts become more severe , climate change etc
• no canopy to intercept= saturated soil etc
• less leaf litter = no humus formed= new growth harder and less carbon absorbed

Question 7

mitigation

Answer 7

• amazon region protected areas programme - created 2002 by Brazilian govt —> aims to restore deforested areas and reduce its impacts —> by 2018 , 60 mill hectares of new parks and reserves created under this
• Brazilian forest code - legalisation on land management , legally required Brazilian Amazon to permanently maintain 80% of land as forest
  BUT—> there’s little repercussions for law breakers and no incentive for farmers not to deforest land
• agroforestry = reduce soil segregation, maintains water balance
• afforestation
• selective logging= only mature trees harvested = allows for forest recovery —> govt monitoring using satellite tech and drones
• ecotourism
• UN-REDD + programme (international agreement)- offers financial incentives for forest protection= reduces emissions from deforestation in LICS —> stresses role of conservation = increase sustainable management and increase forest carbon stock BUT dependent on international funding= unreliable
• indigenous ppl act as forest protectors
• sustainable agriculture e.g. no burning techniques , crop rotation BUT more expensive and requires education etc

Question 8

mitigation issues

Answer 8

• economic pressures and development priorities (growing population and demand for resources etc )
• 2020- over 90% deforestation in Amazon = illegal
• monitoring = hard due to large remote areas = easy for illegal activities to occur
• temps still rising
• trees= take little time to grow, not immediate

Question 9

contribution to climate change

Answer 9

• moving rainforest from carbon sink to source
• 30% anthropogenic emission= from burning rainfirsss r s
• forests disturbed = store less carbon —> impact carbon cycle and climate

Question 10

impacts of climate change on Amazon

Answer 10

• species migration (to more suitable environment—> scientists predict 4% rise in temp could kill 85% of Amazon rainforest and it could be like a Savanna
• species die —> positive feedback loop (decomp of dead material etc)
• temperature effects (higher temp) impacts species etc
• less rainfall and increase temps = decrease freshwater and habitats
• river regime impacted (more floods and soil erosion due to less surface run off )= harms aquatic organisms
• rising sea levels = floods lowland areas

Question 11

impacts of climate change on soils

Answer 11

• deforestation and high temps dries soils = they hold less carbon
• no roots to hold soil = carbon transferred to hydrosphere as rain washes it away
• soil erosion= decomposition etc

Question 12

impacts of climate change on rivers

Answer 12

• disrupt water cycle , more soil erosion and weathering of soils = more flash floods
• risk of increased soil being washed into rivers (leached) etc
• reduce water supply