Comp 3 - Topic 8

Question 1

Give 4 ways in which the abiotic and biotic components of the rainforest are closely related.

Answer 1

• The warm climate means that plants can grow quickly, the dense leaf cover from these plants protects the forest floor from erosion
• The agouti buries brazil nuts, the brazil nut relies on the rodent to pollinate, if they were to become extinct brazil nut population would decrease and the animals and people who rely on them bad effected.
• Epiphytes don’t have access to soil so rely on rain for nutrients.
• deforestation would mean less co2 could be absorbed from the atmosphere causing global warming

Question 2

How are plants adapted to a hot wet climate in the tropical rainforest?

Answer 2

• Emergents are the tallest trees and poke out above the canopies, they only have leaves at the top and have buttress roots.
• The main canopy is a continuous layer of trees which shades the whole forest underneath they also only have leaves at the top.
• The under canopy is full of growing trees that are yet to reach full height.
• The shrub layer is at the bottom the leaves of these plants are broad, large and contain a lot of chlorophyll to absorb sunlight.

Question 3

Give 4 adaptations of the rainforest.

Answer 3

• Drip tips with waxy coating help to stop water building up on the leaves and damaging them.
• many trees have smooth thin bark as there is no need to protect from cold temperatures
• lianas use tree trunks to grow up high
• plants drop leaves all year round so they can go on growing

Question 4

Give 7 ways which animals have adapted to living in the tropical rainforest.

Answer 4

• monkeys which live in the trees have strong limbs to climb trees
• flying squirrels have flaps of skin so they can glide
• tree frogs have suction to help them climb
• some animals are camouflaged
• some animals are nocturnal so they don’t have to deal with day heat
• anteaters are adapted to the low light conditions on forest floor
• most rainforest animals can swim to cross rivers

Question 5

How are nutrients cycled in the tropical rainforest?

Answer 5

1) Trees are evergreen so dead leaves and plant litter fall all year round.
2) The warm, moist climate means fungi and bacteria decompose this plant matter quickly, the nutrients released are soluble and are absorbed into the soil
3) dense vegetation and rapid plant growth means that nutrients are rapidly taken up by plant roots

Question 6

Why does the rainforest have such a high biodiversity?

Answer 6

• It has been around for a very long time allowing lots of time for plants an animals to evolve and form new species
• the layered structure of the forest allows for different environments for different species
• the climate is very constant meaning plants don’t have to be adapted to a changing climate.

Question 7

Why are food webs in tropical rainforests so complex?

Answer 7

• There are so many different species that there are loads of links between them e.g. jaguars eat lots of different mammals.
• some animals are both primary and secondary consumers e.g. fruit bats eat bananas and mice

Question 8

Give 7 threats to the tropical rainforest.

Answer 8

• Local demand for fuelwood, locals chop down trees for charcoal
• Commercial logging, trees chopped for furniture and buildings
• Mining means that lots of area is cleared to mine and for roads
• HEP, when constructed they flood large areas of the river behind them
• Commercial farming is where forests are cleared for cattle or palms
• subsistence farming where farmers farm for themselves
• Biofuels space must be cleared to grow them

Question 9

What are the environmental impacts of deforestation?

Answer 9

• Without roots to hold the soil together it would be washed away by rain
• Without trees to intercept water nutrients are much more easily washed away by the rain
• Trees remove co2 from the atmosphere, deforestation means more co2 in the atmosphere

Question 10

How is climate change affecting the tropical rainforest?

Answer 10

• In some areas temperature is increasing and rainfall is decreasing.
• plants and animals are adapted to moist conditions the dry weather would badly affect them
• droughts lead to forest fires.

Question 11

Why are deforestation rates increasing in some areas e.g. Borneo?

Answer 11

• Poverty - there is more subsistence farmers and more people use wood for fuel.
• Foreign debt - there is lots of money in the tropical rainforest it is an easy way to pay of debt
• Economic development - road and rail projects open up the rainforest to logging, mining and farming

Question 12

Why are deforestation rates decreasing in some areas e.g. Brazil?

Answer 12

• Government policies - it pays landowners to reforest areas and has increased bio tourism.
• International Condemnation - puts pressure on companies by naming and shaming them many countries have pledged 0 deforestation as a result
• Monitoring systems - the global forest watch can stop illegal foresting by tracking the forest with satellites

Question 13

What is REDD? What does it do? What are the advantages and disadvantages of this?

Answer 13

REDD= reduced emissions from deforestation and forest degradation, it aims to reward forest owners for not chopping down the forest.
Advantages:
- It stops the direct causes of deforestation
- biodiversity is not lost
- everyone benefits
Disadvantages:
-deforestation may continue somewhere else
-aspects of REDD are not clear as farmers can still be rewarded by cutting down tress of they replant them with something like palm trees
- It may affect local communities who rely on this

Question 14

What is CITES? What does it do? What are the advantages and disadvantages of this?

Answer 14

CITIES= convention on international trade in endangered species of wild fauna and flora, it is an agreement to tightly control trade in wild animals and plants
Advantages:
- the issue is tackled at a global level
- raises awareness of threats to bio diversity
Disadvantages:
- it doesn’t protect the animals habitat
- some rules are unclear e.g. ivory
- not all countries are part of this

Question 15

What are the economic challenges of sustainable forest management?

Answer 15

Economic:

• The economic benefits of sustainability are long term which is not good for poor countries who need immediate income.
• It is usually more expensive and requires private companies
• sustainable forestry schemes are managed by NGOs if the priorities of these companies change funding could stop

Question 16

What are the environmental challenges of sustainable forest management?

Answer 16

• If trees are replanted this will not resemble the natural forest, the trees are replaced but the ecosystem may not be restored.
• trees which are replanted take a long time to grow and companies may chop down more forest whilst they wait
• selective logging is still damaging

Question 17

What are the social challenges of sustainable forest management?

Answer 17

• sustainable forest management generally provides fewer jobs for local people
• if the population increases the demand for resources in the forest increases

Question 18

What is ecotourism and how does it keep the rainforest safe?

Answer 18

It is tourism which minimises damages and benefits the local people.
Only a small amount of people are let into an area at one time and waste management is good as to not contaminate environment.
It is a source of income for local people as they act as the tour guide so they don’t have to deforest for money

Question 19

What is sustainable farming and how does it keep the rainforest safe?

Answer 19

It protects the soil so that the land remains productive, there is no need to clear new land.

• Agro-forestry is when trees and plants are planted at the same time so plant leaf allows nutrients and also strengthens soil through roots.
• Green manure plants which add nutrients to the soil are planted to maintain soil fertility
• crop rotation is when the crops are cycled from field to field to allow the soil to recover

Question 20

Describe 5 ways in which the taiga forest is interdependent.

Answer 20

• Plants gain nutrients from the soil which provide nutrients for animals who in turn spread seeds through their dung.
• The cold climate causes plants to grown slowly, this means the soil is not very nutrient.
• herbivores migrate to areas with food, carnivores follow
• in summer trees absorb suns heat, it means that the permafrost doesn’t melt. It provides water for the trees
• climate change and deforestation would cause the permafrost to melt, this would flood land and releases trapped co2

Question 21

How are plants in the taiga forest adapted to the cool, dry climate?

Answer 21

• they are evergreen, so they can make good use of the sunlight
• they have needles rather than leaves to reduce water loss by strong cold wins because the SA is reduced.
• the trees are coned shaped so heavy snow doesn’t snap the branches
• the branches are flexible so they snap less easily.

Question 22

How are animals in the taiga forest adapted to the cool, dry climate?

Answer 22

• many larger mammals are migratory, so they can find food.
• many animals are well insulated against the cold temperatures
• some animals hibernate as to survive the cold winters
• some animals have camouflage, snowshoe hares have a white coat

Question 23

Describe the nutrient cycle in a taiga forest.

Answer 23

• Trees are evergreen, so drop their needles all year round
• despite the constant dropping of leaves low temperatures mean it takes a long time for them to decompose this means soil isn’t very fertile.
• the cold climate also means plants grow slowly the rate of transfer of nutrients from soil to plants is low.

Question 24

Why is the biodiversity in taiga forests low?

Answer 24

• The land was cold and covered with ice 15000 years ago which means the plants and animals have had little time to adapt
• There aren’t many different habitats for animals to live leading to a lack of species
• plants grow slowly due to cold climate, leading to a lack of nutrients in the soil. The summers are short meaning less sunlight
• reptiles and amphibians cannot cope with the cold conditions

Question 25

Give 4 ways in which the taiga forest is being exploited

Answer 25

- Logging for softwood, wood for furniture and housing - pulp and paper production, tress are shredded for paper - HEP flood large areas of the forest - mineral mining means clearing lots of the forest - exploitation of fossil fuels: Tar sands are found under boreal forests and can be processed into fossil fuels, it often involves open pit mining, this causes wide scale deforestation

Question 26

How does Acid rain cause a loss of biodiversity in taiga forests?

Answer 26

- burning fossil fuels releases gases such as sulphur dioxide which dissolve in water in the atmosphere to form acids when it rains the acids are deposited on plants and soils. - acid rain effects a plants leaves, the nutrients in the soil and the wildlife living in rivers

Question 27

How do pests and diseases cause a loss of biodiversity in taiga forests?

Answer 27

- normally pests or disease affect one type of tree. Because there is normally only one type of tree in an area in a taiga forest they can cause lots of damage. - it is thought that climate change is making it easier for pests to survive

Question 28

How are forest causing a loss of biodiversity in taiga forests?

Answer 28

- They are a natural part of the ecosystem, they allow new growth and regenerate the forest. - It is thought that climate change is increasing the frequency of forest fires which is not good for the ecosystem

Question 29

What is a wilderness area? What are its strengths and its weaknesses?

Answer 29

It is an are that is undisturbed by human activity that is managed with the aim of protecting the landscape - It has the highest level of protection, most human activity is banned to keep it as untouched as possible, usually covers a large area so migration can take place But: - the areas are hard to police - there us economic pressure on governments to exploit the are - there is pressure to build roads to allow greater access.

Question 30

What is a national park ? What are its strengths and its weaknesses?

Answer 30

An area which is left mostly in its natural state and is managed to protect biodiversity. - it may be established to protect a particular species, often covers a large area and unsustainable activities such as logging and mining are not permitted. But: - they must take in the needs of indigenous communities who may hunt - tourism may be needed to pay for conservation leading to some pollution

Question 31

What is sustainable forestry? What are its strengths and its weaknesses?

Answer 31

It is a way of harvesting wood without damaging the area in the long term. - limits can be placed about the size and number of trees which can be felled, companies may be required to regenerate after logging, selective logging means some trees are left to be part of new forest But: -some countries struggle to enforce these rules - there may be a lack of clear management of the ecosystem -Different groups may not agree with the rules and restrictions

Question 32

What are the views on protecting and exploiting the taiga forest?

Answer 32

- they store lots of carbon, destroying would increase climate change - some species are only found in taiga meaning the destruction of their habitat could lead to extinction - indigenous peoples lives would be altered and destroyed - the demand for resources is increasing - logging provides lots of jobs - the exploitation of the forest is worth lots of money to the country involved