Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physical geography > The Amazon > Flashcards

The Amazon Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards World Geography flashcards
1
Q

What are the main charac.s the Amazon?

A
  • Worlds largest tropical rainforest and covers 40% of South American landmass
  • Hot, wet climate w/ dense vegetation
  • Home to many indigenous ppl
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What % of earth do tropical rainforests cover?

A

6%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What % of global photosynthesis do TRF account for?

A

30-50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What countries does the Amazon spread to?

A

Vast parts of Brazil plus Venezuela, Columbia, Peru and Bolivia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many tress in the Amazon store what amount of earths carbon?

A

15,000 store 1/5 of all carbon in planets biomass.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many trees in the Amazon?

A

300 billion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the intertropical convergence zone?

A

The point where the 2 Hadley cells meet at the Equator. There is low air pressure and high evapotranspiration meaning lots of rain. This results in rich vege. and biodiversity of TRF.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does the water cycle cause the Amazon to be wet?

A

Lots of evaporation over the Atlantic Ocean and air full of moisture is blown towards the Amazon. Contributes to high rainfall.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does warm temp.s mean for the water cycle in the Amazon?

A

High evaporation in rainforest increasing the amount of precipitation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the dense canopy in the Amazon mean for the water cycle?

A

High interception. As a result less water flows into rivers than expected and does so slowly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the average rainfall in the Amazon basin?

A

3000mm per yr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the av. temp. in the Amazon?

A

28 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What % of rainfall is intercepted?

A

75%. Reaches ground thro stem flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What % of all rain Evaporates?

A

25%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What % is used by plants and returned to atmos.?

A

37.5% used by plants and returns to atmos. via evapotranspiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What % infiltrates soil or flows overland into channels?

A

37.5%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What effects is deforestation having on the water cycle?

A

No tree canopy to intercept water so more reaches ground. Too much to soak into soil so there is increased surface runoff leading to flooding. Soils more exposed to sun - dry and baked.

Reduces rate of evapotranspiration - less water vapour reaches atmos. meaning fewer clouds and less rain produced. Increased risk of drought.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the impacts of reduced evapotranspiration on the water cycle?

A
  • Atmos. becomes less humid
  • Transpiration rapidly decreases
  • Reduced evap.tran from cleared areas means air less moist and reduction of cloud cover
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does removal of trees through slash and burn result in?

A

Sudden evaporation of water that was previously retained in forest canopy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is causing less rainfall in the Amazon?

A
  • Particles from burning of trees increases density of airborne aerosols around which water vapour condenses meaning smaller droplets in clouds - too small to precipitate.
  • Forests emit salts and organic fibres w/ water when they transpire. Act as condensation nuclei assisting in cloud and rain production - loss inhibits cloud formation
  • Moisture that does evaporate from deforested areas forms shallow cumulous clouds - don’t precipitate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why has flooding increased in the Amazon?

A

Increased surface runoff. Removal of trees thro slash and burn reduces porosity of soil causing faster rainfall drainage, erosion, silting of rivers and lakes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What did Spracken et al. find could happen if there is further deforestation in the Amazon?

A

Result in 20% decline in regional rainfall as air blowing from the rainforest contains less moisture.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are 3 major drivers of change in the rainforest?

A
  • Lost approx. 17% of primary forest in last 50 yrs
  • 80% of this due to cattle ranching. Other reasons include logging, mining and housing
  • Between 2000 and 2007, 19,386km squared was being destroyed a yr
24
Q

What does increasing CO2 in atmos. mean for Amazon?

A

Amazon is a carbon sink.
Increased productivity in Amazon as vege. more able to access CO2 for photosynthesis and amount of biomass has been increasing.
As result amount of CO2 sequestered by Amazon increased making it more important carbon store.

25
Q

How is carbon released from Amazon as an output?

A

Respiration by plants and animals. Decomposition as bacteria and fungi thrive in warm, wet conditions. Some carbon is also stored within soil and then removed by streams as an output of TRS.

26
Q

What effects is deforestation having on the Amazon in terms of the carbon cycle?

A

Without roots to hold the soil together heavy rail washes away nutrients rich top layer transferring carbon stored in pedosphere to hydrosphere.
Less leaf litter so humus isn’t formed. Soil cannot support new growth so less CO2 absorbed.
Trees remove CO2 from atmos. and store it so fewer trees = more atmos. carbon - greenhouse gas and climate chnge

27
Q

What are the impacts of human activity having on the carbon cycle?

A
  • Release of stored hydrocarbons in massive quantities increases atmos. CO2
  • Deforestation contributing to greenhouse gases
28
Q

What is reintroducing carbon stores and flows in TRS?

A

Replacing rainforest w/ alternatives and uses like crops and pasture reintroduces stores and flows.
Operate at less effective levels.

29
Q

How much CO2 absorb and emit annually?

A

2.2 billion tonnes absorbed annually compared to 1.9 billon tonnes released thro decomp. and respir.

30
Q

What happens when land is burnt for clearance?

A

Between 30 and 60% of CO2 is immediately released into atmos.

31
Q

How much has the Amazon been shrinking by since 2000?

A

0.3%

32
Q

What is happening to amount of carbon the Amazon absorbs?

A

Capacity to absorb carbon is declining. In the 1990s it was absorbing 2 billion tonnes, in 2015 it absorbed 1 billion tonnes. This is less than the total amount of CO2 emitted by Latin America in the same yr.
No longer represents a continental carbon sink.

33
Q

What is the most significant impact of deforestation on the carbon cycle?

A

Photosynthesis ceases until a new plant begins to grow.

34
Q

What is happening to respiration and decomposition?

A

Plant and animal respiration drops to nearly 0 and decomposers are largely absent from the environment.

35
Q

What occurs when it rains in area where trees have been burned?

A

Rain washes ash to the ground which increases soil carbon content. If there is heavy rainfall carbon in run off will increase.

36
Q

How much carbon does the Amazon store?

A

80 - 120 billion tonnes

1-3 gtc

37
Q

What is a negative feedback system in TRS?

A

Biomass is increasing in TRs due to an increase in sequestration of CO2 concentrations.
Assumed that increased Co2 levels encourage biomass growth. Rainforests are growing quicker but dying sooner.

38
Q

How much has rainforest temp.s increased by?

A

0.26 degrees C every 10 yrs since mid 1970s.

By 2050 its estimated that temp.s will increase by 2-3 degrees.

39
Q

How much land was lost a yr between 2000 and 2010?

A

3.6 mil hectares

40
Q

What impact is climate change having on vegetation?

A
  • Species adapted to rainforest conditions, tolerance to temp. seasonality and other changes limited
  • 2009 study - 2 degree temp. rise above preindustrial levels would = 20-40% of Amazon trees dying in 100yrs
  • 3 degree rise would destroy 75% of forest, mainly thro drought
41
Q

What impact is CC having on soils in the TRS?

A
  • Amazonian soil contains 4-9kg of carbon in upper 50cm of soil layer
  • Forest cleared and burned - 30-60% lost to atmos. unburnt veg decays and lost within 10yrs. Soil fungi and bacteria used to recycle dead veg dies off
42
Q

How does CC affect the rivers?

A

Changes in total precip., extreme rainfall events and seasonality:

  • overall reduction in river discharge
  • increase of silt washed into rivers, disrupt river transport routes
  • flash flooding
  • destroy freshwater ecosystems - remove protein source and income to locals
  • destroy water supply of locals
43
Q

What may warming water temp.s do?

A
  • Kill off dependent species
  • Change biodiversity of river system by intro of new species, kills others
  • Reduce water dissolved oxygen concentrations, destroy eggs and larvae which rely on dissolved oxygen
44
Q

What is selective logging and how is it used as mitigation?

A

Only some trees felled, most left standing.
Less damaging than felling all trees in an area. Keeps structure of forest area and canopy is there so soil not exposed.
Means forest can regenerate so limited impact on carbon and water cycles.

45
Q

How is replanting being used as mitigation?

A

New trees replanted to replace those cut down. E.g. Peru replanted over 115 acres between 2016 and 2019.
Important that the same type of tree that is cut down is replanted so variety is kept and local carbon and water cycles return to initial state.

46
Q

What is the TARAPOTO process?

A

Began 1995. Forest policy makers from 8 member countries identified 12 criteria to help manage forest sustainability at management, national and global level.

47
Q

What are the national level priorities of TARAPOTO?

A
  • Investment in research, education and tech transfer

- Existence of policies and legal framework for land-use planning through ecological and economic planning

48
Q

What are the management level priorities

A
  • Proportion of environmental protection areas against permanent production areas
49
Q

What is the Amazon Cooperational Treaty Organisation?

A

Aimed at promoting sustainable development. Made up of 8 member countries. Reverse loss of forest cover worldwide thro sus. management - protection, restoration, afforestation and reforestation. Prevent illegal logging.
Protected areas at regional level can have conservation corridors going thro more than 1 country.

50
Q

What local policies are there for mitigation?

A

Creation of national parks and reserves. Jau National Park is over 5.6 mil hectares and is a UNESCO site. Para rainforest reserve cover 15 mil hectares (bigger than England) and links to existing reserves to form vast conservation corridor in northern Amazon.

51
Q

What is agroforestry and how is it used as mitigation?

A

Combination of crops and natural plants/trees. Many social and environmental advantages over predominant land uses in Amazonia.
Forest not cut away for agriculture - holds more carbon than veg otherwise occupying the site.

52
Q

What is the Brazilian Forest Code?

A

Says that landowners have to keep 50-80% of their land as forest.

53
Q

What natural reserve has been set in Brazil?

A

The Central Amazon Conservation Complex set up in 2003 and protects biodiversity in an area 49,000 km squared big whilst allowing local ppl to use it sustainably.

54
Q

What is reforestation and how is it used as mitigation?

A

Planting trees in area w/ almost no trees. Carbon is sequestered, incorporated into tree biomass and can be stored for varying amounts of time.

55
Q

How is sus. forest management used as mitigation?

A

Often suggested as form of sequestration. Carbon in wood converted to long-lived wood products remains out of atmos while trees in location can regrow and continue to absorb carbon.

56
Q

What can enhance reforestation efforts?

A

Seedlings of native species can be grown in local nursery and planted in degraded forests. Encourages growth of native tree species including threatened ones to increase biodiversity.

Physical geography (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions