Case Study - Amazon - p1

Question 1

effects of deforestation

Answer 1

• decrease in biodiversity
• increased gg emissions
• incraesed ssoil erosion
• drier climate, disrupts water cycle

Question 2

where is tropical rainforest in brazil

Answer 2

• lowland basin
• in west
• quite accesible

Question 3

deforestation in brazil

Answer 3

20% destroyed since 70s

Question 4

7 causes of deforestation

Answer 4

• Settlement and population
• Logging
• Illegal trade in Wildlife
• Commercial farming: cattle
• Energy Development
• Mineral Extraction
• Road building
• Commercial farming: crops

Question 5

Settlement and population

Answer 5

• Most of the uses of the tropical rainforest have a common knock-on effect: they need workers, and workers and their families need homes and services
• This, in turn, means clearing forests to build settlements where these people can live
• huge challenges presented by these causes of deforestation are their scale, speed and wasteful use of the forests land and resources.

Question 6

Logging

Answer 6

• Logging is the first step in conversion of forest land to other uses, but the final use of cleared rainforest that is recorded as the land use
• Only trees chopped down by Timber companies are recorded as logging
• Timber companies are most interested in trees like mahogany + teak, + sell them to other countries to make furniture (selective logging)
• Smaller trees are often used as wood for fuel / made into pulp or charcoal
• Vast areas of rainforest are cleared in one go (clear felling)

Question 7

Illegal trade in Wildlife

Answer 7

• Hunting, poaching and trafficking in wildlife and animal parts are still big business in Brazil
• though this isn’t a direct cause of deforestation, it is endangered species like jaguars, golden-bellied capuchin + golden lion tamarind
• It’s also upsetting the natural balance of the rainforest ecosystem and therefore degrading it

Question 8

Commercial farming: cattle

Answer 8

• Large areas of the amazon rainforest have been cleared to make way for livestock rearing
• rearing of cattle is believed to account for 80% of the tropical rainforest destruction in Brazil
• However, the land can’t be used for long
• quality of the pasture quickly declines
• cattle farmers then have to move on and destroy more rainforest to create new cattle pastures

Question 9

Energy Development

Answer 9

• An unlimited supply of water + ideal river conditions have encouraged dams to be built to generate hydroelectric power (HEP)
• This often involves flooding vast areas of rainforest
• Often dams have a short life
• submerged forest gradually rots, making water very acidic
• This then corrodes the HEP turbines
• dams also become blocked with soil washed down deforested slopes by the heavy rain

Question 10

Mineral Extraction

Answer 10

• some of the minerals developed countries need are found beneath stretches of tropical rainforest
• In the Amazon, mining is mainly about gold
• In 1999, there were 10,000 hectares of land being used for gold mining
• Today the area is >50,000 hectares
• The rainforest suffers badly as it is clear-felled
• same applies to the extraction another mineral: bauxite from which aluminium is made

Question 11

Road building

Answer 11

• Roads are needed to bring in equipment and transport products to markets, but road building means cutting great swathes through rainforests
• Additionally a road built for one particular commercial activity makes forest accessible to other exploiters of rainforest resources
• The Trans-Amazonian Highway began construction in 1972 + is 4,000km long
• though only a small part of it is paved, it has played an important in opening up remote areas of the Amazon rainforest

Question 12

Commercial farming: crops

Answer 12

• forest is being cleared to make way for vast plantations, where crops like bananas, palm oil, pineapple, sugar cane, tea + coffee are grown
• cultivation of soybean has caused much forest clearance in Amazonia
• amount of rainforest cleared for this crop doubled in 1990 - 2010
• soil won’t sustain crops for long
• After a few years, farmers have to cut down more rainforest for new plantations
• Growing sugar cane for biofuel is beginning to become a major crop

Question 13

value of rainforest

Answer 13

• home for indigenous tribes
• medicine
• sense of awe and wonder
• source of wealth for NEEs
• habitats for ENDEMIC species
• biodiversity (170000 plant species, 487 tree species in 1 hectare, 50000 species lost yearly)
• carbon sink
• interdependence

Question 14

global impacts of deforestation

Answer 14

global warming + biodiversity

Question 15

global warming

Answer 15

• tree canopy absorbs CO2 in atmosphere, stops when trees are felled so more CO2 remains in air
• fire used to clear forests means CO2 returns to atmosphere
• leads to other sources of GG eg methane
• a main contributor to greenhouse effect

Question 16

loss of biodiversity

Answer 16

• individual species become endangered/extinct
• estimated 137 plant, animal + insect species lost daily
• new research shows parts could lose 30-40% of main species by 2030
• possible cures for diseases disappear with extinction

Question 17

local impacts of biodiversity

Answer 17

• droughts
• soil erosion + fertility
• river pollution
• decline of indigenous tribes
• conflicts

Question 18

droughts

Answer 18

• climate change
• disrupts water cycle
• fewer trees, less evapotranspiration
• water recycling = a cooling system
• as recycling is reduced, becomes warmer
• drier atmosphere
• bad agriculture etc

Question 19

soil erosion + fertility

Answer 19

• less interception, torrential + convectional rainfall
• when cleared, thin top soil is quickly removed by heavy rain
• bare slopes are prone to gulleying and soil erosion
• once topsoil is removed there is little chance of regrowth
• also leads to silting up of river courses
• even when soil is protected, it loses its little fertility
• grazing + plantations do little to help
• decline in fertility leads to abandonment of pastures + plantations so more area are cleared

Question 20

river pollution

Answer 20

• gold mining causes deforestation
• mercury used to separate gold from ground enters rivers
• fish + ppl are poisoned
• also polluted by soil erosion

Question 21

decline of indigenous tribes

Answer 21

• only 240 tribes left vs 330 in 90s
• many forced to leave by construction of roads, logging, creation of ranches, plantations + reservoirs, opening of mines
• most displaced ppl forced into towns + cities
• addicted to drugs + alcohol is common + many die young
• detailed knowledge (e.g. medicine) lost
• home to 1mil
• make living through substinence farming/ hunting/ gathering/ lo impact harvesting
• now know they have right to remain so are less easily persuaded

Question 22

conflicts

Answer 22

• disputes between indigenous + loggers + other developers of rainforest end in conflict
• different views

Question 23

Why does the tropical rainforest need to be managed sustainably?

Answer 23

• If goods + services of rainforest aren’t protected, then they will soon be lost forever.
• Sustainable management means using goods + services in a way that they are available for people in the future
• Further large-scale deforestation has no place in sustainable management of the rainforest as resources will become exhausted
• Lungs of the earth – Carbon sink, impacts global warming + climate change
• Endangered species – many species that live/grow only in rainforest will become endangered/extinct
• Possible undiscovered cures for illnesses
• Finely balance ecosystem – knock on effect on other ecosystems
• Economic value – many countries with rainforests LIC/NEE though they need to develop the rainforest for economic development, they need it to be sustainable, if rainforests are destroyed economic uses such as logging become unviable

Question 24

stratageies for managing tropical rainforests

Answer 24

• ecotourism
• selectibe logging
• international agreements
• debt reduction
• conservation + education