Tropical rainforests

Question 1

where are Tropical rainforests ?

Answer 1

• found in a narrow band between 10 degrees north and 10 degrees south of the equator
• there are some exceptions, particularly in the southern hemisphere
• there are rainforests in South and Central America, Africa, Oceania, and Asia

Question 2

why are tropical rainforests located here?

Answer 2

• high levels of insolation by the equator - ground is heated intensely by the sun
• this causes the air to rise which creates a low-pressure zone on the earth’s surface
• as the air rises, it cools and forms cumulonimbus clouds

Question 3

climate

Answer 3

• very wet - 2000mm of rainfall per year
• very warm - average daily temp of 28 degrees C
• hot & humid
• same climate all year round - no seasons

Question 4

soils

Answer 4

• red in colour (rich in iron)
• not fertile - heavy rain washes the nutrients out of the soil, but a thin layer of fertile soil is found at the surface where decomposers break down leaves, recycling the nutrients

Question 5

biodiversity

Answer 5

• TRF have a high level of biodiversity - higher than any other biome
• the warm and wet conditions are perfect for plant growth, which supports other species
• rainforests contain 50-90% of the world’s species

Question 6

interdependence

Answer 6

• main components: climate, soil, vegetation and animals
• it is also possible for indigenous tribes to live as part of, and in harmony with the ecosystem
• equally, human activity can badly upset the ecosystem’s balance

Question 7

layers

Answer 7

• emergents
• canopy
• under canopy
• shrub layer
• forest floor

Question 8

animal adaptations

Answer 8

3 toed sloth:
algae grows on their fur - helps with camouflage
curved feet and sharp claws to grasp branches
flying frog:
oversized toe pads - to help them stick to tree trunks
skin flaps on each arm and leg - allows it to glide from plant to plant

Question 9

plant adaptations

Answer 9

kapok tree:
buttress roots - help support base of tree and transport water
large surface area - help CO2/O2 exchange
liana:
climb up the trees to reach sunlight - gets nutrients from the air
thick, woody stems - attach onto trees

Question 10

deforestation

Answer 10

the large-scale cutting and/or burning of forests

Question 11

how have rates of deforestation changed?

Answer 11

-increased from 1700 to 1979 by 32 times
-since 1979 the rate of deforestation has fallen by at least 100 million hectares.
-rates of deforestation have increased in Asia and South America
-Brazil has seen the highest annual deforestation rates (over 3 million hectares) closely followed by Indonesia with just over half Brazil’s rate of
deforestation

Question 12

where is the Amazon rainforest?

Answer 12

• located between the latitude of approximately 10 degrees North and 20 degrees South of the Equator
• the Amazon rainforest is in the North of South America
• the Amazon is in nine different countries, but 60% of it is in Brazil

Question 13

causes of deforestation in the Amazon

Answer 13

80% - cattle ranching
10% - commercial farming
3% - logging
2% - road building
2% - energy development
2% - mineral extraction
1% - building new settlements

Question 14

negative impacts of deforestation

Answer 14

-loss of biodiversity - species such as golden-bellied capuchin and the golden lion tamarind
are endangered - illegal trade in wildlife
-soil erosion - no trees to intercept rainfall, eroded soil is washed into rivers, polluting them

Question 15

positive impacts of deforestation

Answer 15

• mining industry creates jobs for local people e.g. the Buenaventure mining company employs over 3,100 people
• these TNCs pay taxes to the government which can be used to improve public services such as education, healthcare and water supply

Question 16

what goods are provided from TRF?

Answer 16

Goods are things that can be obtained directly from the rainforest

• rubber
• food such as nuts and fruit
• medicines

Question 17

what services are provided from TRF?

Answer 17

Services are benefits that the rainforest can offer to both people and the environment

• the rainforest is a natural carbon sink - absorbs carbon dioxide
• rainfall is intercepted, which reduces the risk of flooding,
• air purification

Question 18

what international agreements have been put in place to manage TRF?

Answer 18

-The International Tropical Timber Agreement
(ITTA) was signed in 2006 by both producers and consumers of timber - aims to promote sustainable timber trade and restrict illegal felling;
trees are marked with a registration number
-CITES is another international agreement. Created in 1973, it aims to reduce illegal trade of wild animals and plants.

Question 19

debt reduction

Answer 19

countries are relieved of some of their debt in return for protecting their rainforests.

Question 20

how can conservation and education manage TRF?

Answer 20

• NGOs help by educating the public, training conservation workers and even buying up threatened areas in order to create nature reserves
• rely on donations and volunteers to operate.

Question 21

selective logging and replanting

Answer 21

Selective logging is when trees are cut down when they are fully grown, while smaller trees are left to mature and grow.
Replanting involves growing seeds in a nursery; the saplings are then planted into deforested areas.

Question 22

ecotourism

Answer 22

• ecotourism is defined as: “Responsible travel to natural areas that conserves the environment and improves the welfare of local people”.
• Whilst it benefits indigenous communities, often the visitors have travelled thousands of miles, and so it does have environmental impacts