Topic 8 - Forests under threat

Question 1

Is climate biotic or abiotic?

Answer 1

abiotic

Question 2

Is vegetation biotic or abiotic?

Answer 2

biotic

Question 3

Is soil biotic or abiotic?

Answer 3

abiotic

Question 4

Are animals biotic or abiotic?

Answer 4

biotic

Question 5

What are biotic components of an ecosystem?

Answer 5

Living parts of an ecosystem, e.g. animals, plants

Question 6

What are abiotic components of an ecosystem?

Answer 6

Non living parts of an ecosystem, e.g. Climate, air

Question 7

How are climate and vegetation interdependent in tropical rainforests?

Answer 7

The warm and climate means that plants grow quickly. Epiphytes grow on other plants and are not rooted in the soil, therefore they depend on rainfall for nutrients and water. If lots of vegetation is deforested, the amount of CO2 being absorbed will decrease, this will enhance the greenhouse effect causing climate change (global temperature increase)

Question 8

How are vegetation and soil interdependent in tropical rainforests?

Answer 8

The dense vegetation prevents the soil on the forest floor being eroded and washed away (along with all the minerals within it) by wind and heavy rainfall. This is because the leaves intercept it and prevent it washing away the soil. The roots also hold the soil together. When the vegetation dies it releases nutrients into the soil that allows other plants to grow. Plants are also reliant on the soil to provide water and nutrients

Question 9

How are vegetation and animals interdependent in tropical rainforests?

Answer 9

Symbiotic relationships between plants and animals are common in the rainforests. The lack of wind near the forest floor means that plants have to rely on animals for pollination, some animals also rely on the vegetation for food to survive. An example of this symbiotic relationship is the Agouti and the brazil nut tree: The Agouti is one of the few animals who can crack open the hard seed pod of the brazil nut to eat the nut inside. Sometimes the agouti bury the nuts - these can sprout into new seedlings. Without the agouti the number of brazil nut trees would decline, along with all the animals that live in or feed on it for survival.

Question 10

How are animals and soil interdependent in tropical rainforests?

Answer 10

Dead animals decay and animal droppings fertilise the soil, allowing plants to grow.

Question 11

How are climate and soil interdependent in tropical rainforests?

Answer 11

For soil to be fertile, dead animals and dead vegetation must decay and release nutrients into the soil. The warm, wet climate means that the dead biotic components decay quickly and release nutrients into the soil quickly.

Question 12

What is a symbiotic relationship?

Answer 12

A symbiotic relationship is when 2 different biotic components of a ecosystem rely on each other for survival

Question 13

How have lianas (climbing plants) adapted to life in the tropical rainforest?

Answer 13

Lianas wrap around and grow on other trees. This allows them to quickly and easily reach the sunlight needed for growth. This means that they don’t waste energy on growing strong roots and a trunk

Question 14

How have Epiphytes adapted to life in the tropical rainforest?

Answer 14

Epiphytes grow on other trees. They are not parasitic and get nutrients from rainfall. They reach sunlight quickly and easily without competition

Question 15

How have Buttress roots adapted to life in the tropical rainforest?

Answer 15

Buttress roots are large wide roots that are used to support emergent trees that grow up to 70m tall. They are wide but shallow as the nutrients are near the top of the soil

Question 16

How have drip tip leaves adapted to life in the tropical rainforest?

Answer 16

Drip tip leaves are waxy and channel the water so that it runs off - this prevents standing water growing algae on the leaves. This is important as algae would limit the area for photosynthesis. It also prevents the weight of the water damaging the plant growing. The water is channelled towards the roots where it can be absorbed

Question 17

What are stratified layers?

Answer 17

There are many different layers of rainforest - emergents, main canopy, under canopy , and shrub layer

Question 18

How have emergents adapted to life in the tropical rainforest?

Answer 18

the emergents are the tallest trees, which poke out of the main canopy layer. They have straight trunks and only have branches and leaves at the top where they can get light. They also have big buttress roots to support their trunks

Question 19

How have the main canopy layer adapted to life in the tropical rainforest?

Answer 19

The main canopy is a continuous layer of trees. Like emergents, they only have leaves at the top. The dense layer of leaves shades the rest of the forest

Question 20

How has the under canopy adapted to life in the tropical rainforest?

Answer 20

The under canopy is made up of younger trees that have yet to reach their full height. They can only survive where there are breaks in the canopy to let a little bit of light through

Question 21

How have the shrub layer adapted to life in the tropical rainforest?

Answer 21

The shrub layer is nearest to the forest floor where it is quite dark. Shrubs have large, dark, broad leaves to absorb as much of the available light as they can

Question 22

How are some animals adapted to the fact that food is in the canopy in the tropical rainforest?

Answer 22

Much of the food is in the canopy, this means they must be able to reach the food. Adaptations include, apposable thumbs for climbing (monkeys), strong limbs (jaguars), claws to climb (sloths), flaps of skin that allow them to glide between trees (flying squirrels), and suction cups for climbing (tree frogs)

Question 23

How are some animals adapted to the fact that there are predators in the tropical rainforest?

Answer 23

Many animals are prey to other predators meaning they must be able to protect themselves or prevent being spotted. Adaptations include: Camouflage to hide from predators (leaf-tailed gecko)

Question 24

How are some animals adapted to high temperatures in the tropical rainforest?

Answer 24

Many animals are nocturnal (for example, sloths), this means that they sleep through the day and feed at night when it is cooler, this helps to save energy

Question 25

How are some animals adapted to water and rainfall in the tropical rainforest?

Answer 25

Many animals are able to swim due to large bodies of water. example of this are jaguars and sloths. This allows them to cross river channels

Question 26

How are some animals adapted to low light levels in the tropical rainforest?

Answer 26

Some animals are adapted to the low light levels on the rainforest floor, e.g. anteaters have a sharp sense of smell and hearing, so they can detect predators without seeing them

Question 27

What are the 3 nutrient stores in a tropical rainforest?

Answer 27

Biomass, Litter, Soil

Question 28

What is the largest store of nutrients in the tropical rainforest?

Answer 28

Biomass

Question 29

Why is biomass the largest store of nutrients in the tropical rainforest?

Answer 29

Layers of vegetation and huge trees store large amounts of nutrients

Question 30

Why is there rapid decomposition in the tropical rainforest?

Answer 30

In hot and wet conditions, bacteria and fungi decay dead matter quickly, returning nutrients to the soil

Question 31

Why is soil poor/infertile in the tropical rainforest?

Answer 31

heavy rainfall throughout the year brings in nutrients, but the constant flow of water through the soil removes them (leaching)

Question 32

Why are nutrients washed out of the soil in a tropical rainforest?

Answer 32

Leaching and a constant water flow washes the nutrients out of the soil in a tropical rainforest

Question 33

Explain the nutrient cycle in a tropical rainforest and why it is very rapid

Answer 33

Trees in a tropical rainforest are evergreen deciduous trees, this means that there is a constant supply of litter all year round. The warm, moist climate means that fungi and bacteria quickly decompose the dead organic matter. The nutrients are soluble and are soaked up by the soil. The weathering and breakdown of rocks beneath the soil also releases nutrients into the soil. However, some of the nutrients in the soil are washed out of the soil by leaching and a constant water flow. Dense vegetation and rapid plant growth means that nutrients are rapidly taken up by plant’s roots

Question 34

What is an example of a producer in the tropical rainforest?

Answer 34

Banana tree

Question 35

What is an example of a primary consumer in the tropical rainforest?

Answer 35

grasshoppers

Question 36

What is an example of a secondary consumer in the tropical rainforest?

Answer 36

Tree Frogs

Question 37

What is an example of a tertiary consumer in the tropical rainforest?

Answer 37

Jaguar

Question 38

Explain why the rainforest has such a rich and complex food web:

Answer 38

There are many different layers in the rainforests food web, this means that a producer (such a banana tree) are vital to the survival of a tertiary consumer (such as a jaguar) even though the tertiary consumer could not survive by eating them. This is because without the producer (such a banana tree), primary consumers (such as a grasshopper) could not survive, therefore secondary consumers (such as a tree frog) could not survive as they hunt and eat the primary consumers. As a result the tertiary consumers (such as a jaguar) could not survive as they hunt and eat the secondary consumers

Question 39

What is a producer in a food web?

Answer 39

A producer makes their own food, i.e. by using photosynthesis. They are eaten by primary consumers

Question 40

Are animals confined to 1 category within the food web?

Answer 40

No, some animals can be in multiple categories. For example, fruit bats are both primary and secondary consumers as they eat the fruit of banana trees but also eat mice, which in turn have eaten grass

Question 41

What is biodiversity?

Answer 41

Biodiversity is the variety of organisms living in a particular area - both animals and plants

Question 42

Why does the tropical rainforest have such a high level of biodiversity?

Answer 42

Rainforests have a high level of biodiversity, they contain 50% of the worlds plant, animal, and insect species This is because:

• The rainforest has been around for a long time and without the climate changing
• The layered structure and stratified layers of the rainforest provides many different habitats
• Rainforests are stable environments - it is hot and wet all year round

Question 43

Why does the fact that the rainforest has been around for a long time and without the climate changing very much cause high biodiversity in the tropical rainforest?

Answer 43

The rainforest has been around for a long time and without the climate changing very much, so there has been lots of time for plants and animals to evolve and form new species

Question 44

Why does the fact that there is a layered structure and stratified layers cause high biodiversity in the tropical rainforest?

Answer 44

The layered structure and stratified layers provides many different habitats within 1 ecosystem. Plants and animals adapt to become highly specialised to their particular environment and food source so many different species develop

Question 45

Why does the fact that Rainforests are stable environments cause high biodiversity in the tropical rainforest?

Answer 45

Rainforests are stable environments - they are hot and wet all year round. They are also very productive (plants grow very quickly, creating lots of biomass) because of the high rate of nutrient cycling. This means that plants and animals don’t have to cope with changing conditions and there is always plenty to eat - so many offspring survive and they are able to specialise

Question 46

What does interdependent mean?

Answer 46

The components of the ecosystem are closely linked and are dependent on each other - if 1 changes, the rest are affected

Question 47

How are climate and vegetation interdependent in taiga forests?

Answer 47

The cold climate causes plants to grow slowly and also decompose very slowly. In summer, the trees absorb heat and shade the ground below, this prevents the permafrost from thawing. The permafrost also provides water for the plants

Question 48

How are soil and vegetation interdependent in taiga forests?

Answer 48

Plants gain nutrients and water from the soil. The plants decompose and provide nutrients for the soil, however the plants decompose very slowly causing the soil to be relatively low in nutrients - further reducing the ability of plants to grow

Question 49

How are climate and animals interdependent in taiga forests?

Answer 49

herbivores must migrate south in the winter to areas where the moss is able to grow as the ground freezes in the north, carnivores (such as wolves) must then follow the herbivores.

Question 50

How are animals and soil interdependent in taiga forests?

Answer 50

When animals die, their bodies decompose in the soil and provide nutrients in the soil

Question 51

How are plants and animals interdependent in taiga forests?

Answer 51

Animals spread the seeds of plants in their dung, this helps plants to reproduce. Many animals (herbivores) rely on vegetation such as mosses to survive.

Question 52

How are cone shaped trees adapted to life in the taiga?

Answer 52

The heavy winter snowfall can slide straight off the branches without breaking them. The branches are also quite bendy meaning that they are less likely to snap

Question 53

How are needle like leaves adapted to life in the taiga?

Answer 53

Trees in the taiga have needles instead of flat leaves, this reduces water loss from strong, cold winds because it reduces the surface area.

Question 54

How are tall trees adapted to life in the taiga?

Answer 54

Being tall allows the trees to absorb as much sunlight as they can

Question 55

How are dark coloured trees adapted to life in the taiga?

Answer 55

The trees are dark green, allowing them to absorb as much light as possible. They are also evergreen and do not lose all their leaves at once

Question 56

How are woody pine cones adapted to life in the taiga?

Answer 56

Seeds are protected by woody pine cones

Question 57

What type of trees are found in the taiga forest?

Answer 57

Conifers

Question 58

How are some animals in the taiga adapted to the temperatures?

Answer 58

Many animals are well-insulated against the winter cold, an example of this is thick fur or layers of feathers. Some animals also hibernate to conserve energy and survive the winter

Question 59

How are some animals in the taiga adapted to predators?

Answer 59

Some animals have white coats in the winter, so they are camouflaged against the winter snow - this helps them hide from predators. Camouflage also helps predators sneak up on prey undetected. Some animals also have large ears to allow them to hear better and hear prey or predators1

Question 60

How are some animals in the taiga adapted to changing seasons?

Answer 60

During colder winters the land in the northern areas freezes over meaning that food cannot grow. This causes many larger mammals to migrate in search of areas where food can still grow

Question 61

What is the largest nutrient store in the taiga?

Answer 61

Litter

Question 62

Why is litter the largest nutrient store in the taiga?

Answer 62

Leaf fall is abundant as the trees are evergreen, this means that the needles drop all year round. Decomposition is slow due to low temperatures and little precipitation

Question 63

What is the smallest nutrient store in the taiga?

Answer 63

Soil

Question 64

Why is soil the smallest nutrient store in the taiga?

Answer 64

Decomposition of litter is slow due to low temperatures and little precipitation. There is also few nutrients added as there is little rain or snow and breakdown of rock is slow

Question 65

explain why biomass has a moderate level of nutrients in the taiga

Answer 65

There are not many nutrients in the soil and the climate is cold causing poor conditions for growth. However vegetation is evergreen meaning that plants maintain their pines all year allowing them to photosynthesise throughout the year and grow all year round

Question 66

Why is there slow nutrient cycling and slow plant growth in the taiga?

Answer 66

The taiga has a cold climate and dos not have much rainfall

Question 67

Why is there rapid nutrient cycling and fast plant growth in the Tropical rainforest?

Answer 67

The tropical rainforest is a warm climate with abundant rainfall

Question 68

Explain the nutrient cycle in the taiga and why it is slow

Answer 68

In the taiga, trees are evergreen so they drop their needles throughout the entire year, this creates a large supply of litter. However, surface run off such as snow melt carries some of these nutrients away. Despite the constant leaf fall, low temperatures mean that it takes a long time for the litter to decompose and be added to the soil - conditions are too harsh for many decomposers. There is also few nutrients added as there is little rain or snow and breakdown of rock is slow. This means that the soil is not very fertile. The cold climate and infertile soil also means that plants grow slowly - the rate of transfer of nutrients from soil to plants is low.

Question 69

Explain why taiga forests have low biodiversity compared to Tropical Rainforests

Answer 69

• The land was much colder and used to be covered by ice
• The simple structure means there are not many habitats
• Taiga forests are much less productive than Tropical rainforests
• Some groups of animals are under-represented

Question 70

Explain why the fact that the land in the taiga was much colder and used to be covered by ice causes it to have low biodiversity

Answer 70

The land was much colder and was covered by ice until around 15,000 years ago. Species have had relatively little time to adapt to the current climate. Plant growth is also slower, this means there is not as much food available, causing there to be fewer animals and animal species

Question 71

Explain why the fact that the taiga has a simple structure causes it to have low biodiversity

Answer 71

The simple structure means that there aren’t many different habitats - there are fewer ecological niches for organisms to fill, so fewer varieties of species

Question 72

Explain why the fact that the taiga forest is much less productive than tropical rainforests means that it has low biodiversity

Answer 72

Taiga forests are much less productive than tropical rainforests (plants grow slowly, so there is less biomass) and nutrients take a long time to be returned to the soil because it is so cold. The growing season is also very short - just a few months in the summer. This means that there is not much food available, so there is a constant struggle for survival

Question 73

Explain why the fact that some groups of animals in the taiga are under-represented means that there is low biodiversity

Answer 73

Some groups of animals are under-represented, there aren’t many amphibians or reptiles because they cannot cope with the cold climate (reptiles are cold blooded meaning they cannot regulate their own body temperature and depend on the sun to stay warm)

Question 74

What is a direct threat?

Answer 74

A direct threat is an immediate human impact

Question 75

What is an indirect threat?

Answer 75

An indirect threat is a long term impact that happens unintentionally (caused by a direct impact)

Question 76

Name 6 direct impacts to the tropical rainforest:

Answer 76

• Commercial Farming
• Logging
• Minerals
• Subsistence Farming
• HEP (Hydroelectric power)
• Biofuels

Question 77

How is commercial farming a threat to the tropical rainforest?

Answer 77

Forest is cleared to make space for cattle grazing, or for huge palm oil or soya plantations

Question 78

How is Logging a threat to the tropical rainforest

Answer 78

Trees are felled to make furniture and for construction. Road building for logging also requires more tree clearance. Local people chop down trees to use as fuel or to burn to make charcoal

Question 79

How are mineral resources a threat to the tropical rainforest?

Answer 79

Minerals (e.g. gold, copper, and iron ore) are often found in tropical rainforests. Explosives are sometimes used to clear earth or deep pits are dug to reach the deposits

Question 80

How is subsistence farming a threat to the tropical rainforest?

Answer 80

Parts of the forest is cleared so that farmers can grow food for themselves and their family. In small quantities this is fine, but it is happening too often by too many people so the soil is becoming infertile and the forest cannot regrow

Question 81

How is HEP (Hydroelectric power) a threat to the tropical rainforest?

Answer 81

Many tropical rainforests have large rivers. Building dams to generate hydroelectric power floods large areas of forest behind the dams

Question 82

How are biofuels a threat to the tropical rainforest?

Answer 82

Biofuels are fuels made from plants. Growing the crops needed to make biofuels takes up large amounts of land - trees have to be cut down to make space for them

Question 83

List 4 reasons for why deforestation is increasing in the tropical rainforest

Answer 83

• Poverty
• Debt
• Economic Development
• Demand for resources

Question 84

List 4 reasons for why deforestation is increasing in the tropical rainforest

Answer 84

• Poverty
• Debt
• Economic Development
• Demand for resources

Question 85

How does poverty increase the demand for deforestation in the tropical rainforest?

Answer 85

Population growth and poverty in many low income countries can cause an increase in small-scale subsistence farming, local people cut down small areas of forest for land to farm because they have no other way of making a living, therefore increasing deforestation

Question 86

How does foreign debt increase the demand for deforestation in the tropical rainforest?

Answer 86

Many poorer countries have large foreign debts which can be difficult to pay off, there is a huge market of goods in the tropical rainforest, so countries are driven to cut down forests, export timber, or grow cash crops as an easy way to pay off debts that they owe to richer countries

Question 87

How does economic development increase the demand for deforestation in the tropical rainforest?

Answer 87

Most tropical forests are in the developing world. In order to develop their economies, forest is sacrificed in place of roads, expanding cities, and to dam rivers and build hydroelectric power. Road and rail projects are also created to promote further development. These open up areas of the rainforest to logging, mining, and farming

Question 88

How does a demand for resources increase the demand for deforestation in the tropical rainforest?

Answer 88

Tropical rainforests contain raw materials. These include timber, but also oil, gas, iron ore and gold. To get these, forest has to be destroyed. Land is also needed to feed growing populations

Question 89

List 3 reasons why deforestation is decreasing in the tropical rainforest

Answer 89

• Government policies
• International condemnation
• Monitoring systems (satellite technology and GIS)

Question 90

How do government policies cause deforestation to decrease in some places?

Answer 90

In some countries government policies help to reduce deforestation. An example of this is the Costa Rican government investing in ecotourism and paying landowners to reforest area. This causes forest cover to increase

Question 91

How does international condemnation cause deforestation to decrease in some places?

Answer 91

International condemnation puts pressure on companies by naming and shaming those that are involved in deforestation. Many companies have pledged zero-deforestation as a result

Question 92

How do monitoring systems cause deforestation to decrease in some places?

Answer 92

Until recently, it was hard to know how much forest was being cut down. Satellite technology allows this to be tracked and it is much easier to find out what has been deforested. They can also track areas that should be protected and track if there is any illegal logging happening, if so it means that the authorities can act more quickly to stop the illegal logging. An example of this is “Global Forest Watch” which provides satellite data to track forest loss

Question 93

Explain 3 environmental impacts of deforestation

Answer 93

1) With no trees to hold the soil together, heavy rain washes it away (soil erosion). This can lead to landslides and flooding
2) Without a tree canopy to intercept rainfall and tree roots to absorb it, more water reaches the soil. This reduces the soil fertility as nutrients in the soil are washed away (leached), out of reach of plants
3) Trees remove carbon dioxide from the atmosphere. Also, burning vegetation to clear forest produces carbon dioxide. Therefore, deforestation means that there is more carbon dioxide in the atmosphere which adds to the enhanced greenhouse effect

Question 94

Is climate change a direct or indirect impact to the forest?

Answer 94

Indirect imact

Question 95

Explain how climate change is an indirect impact to tropical rainforests

Answer 95

Climate change can severely impact tropical rainforests. In some areas temperature is increasing and rainfall is decreasing, which can lead to drought. Droughts lead to ecological stress - plants and animals living in tropical rainforests are adapted to moist conditions, so many species die in dry weather. Frequent or long periods of drought can lead to extinction of some species. Droughts can lead to forest fires, which can destroy large areas of forest

Question 96

Explain how droughts are an indirect impact to the tropical rainforest

Answer 96

Droughts are in indirect impact to the tropical rainforest. Droughts dry the lead litter so that decomposer organisms die out, threatening the nutrient cycle. It also causes leaves in the canopy to die, reducing the food supply and affecting food webs. Droughts struck southern Amazonia in 2014, some scientists now argue that deforestation is making droughts more common and more severe . Also, with fewer trees there is less evaporation and transpiration, this means fewer clouds and less rain

Question 97

Explain what impacts forest fires could have on the rainforest

Answer 97

Forest fires destroy trees and vegetation, this destroys habitats and food for animals, causing them to migrate to other areas. Forest fires also cause a loss of trees and vegetation, this reduces the number of trees that can photosynthesise causing an increase in global temperatures, this can cause permanent damage

Question 98

explain how droughts can lead to ecosystem stress

Answer 98

As temperatures increase and the environment becomes drier and hotter, this can cause droughts which can lead to ecosystem stress. As conditions become drier and hotter, plant and animal species adapted to these conditions would spread out and outcompete the other species which are not adapted to these conditions, this could disrupt the natural cycle. Droughts also increase the possibility of natural forest fires, this can destroy large areas of forest and kill many animals. This could disrupt the natural nutrient cycle, putting stress on the ecosystem

Question 99

explain, step by step, the changes the tropical rainforest faces as global warming increases

Answer 99

1) Global warming will increase global temperatures
2) this will result in the tropical rainforest becoming drier and warmer
3) This will increase the rate of transpiration and evaporation and decrease rainfall
4) This can cause droughts
5) Droughts increase the risk of natural forest fires
6) Forest fires destroy habitats and vegetation
7) The loss of photosynthesising plants causes more climate change
8) This causes desertification and permanent damage to the rainforest

Question 100

Name 3 direct threats to the taiga:

Answer 100

• Deforestation - Logging for softwood
• Deforestation - Pulp and paper production
• HEP (Hydroelectric power)

Question 101

Name 4 indirect threats to the taiga forest:

Answer 101

• Melting permafrost
• Exploitation of materials
• Exploitation of fossil fuels (tar sands)
• HEP (Hydroelectric power)

Question 102

Explain how logging for softwood is a direct threat to the taiga

Answer 102

Trees are cut down so that they can be made into housing, furniture, and matches

Question 103

Explain how Pulp and paper production is a direct threat to the taiga

Answer 103

Felled trees are mashed into pulp and used to make paper. The demand for paper is constant and is rapidly increasing, this is due to an increasing population and therefore demand for paper. This threatens the taiga as it is a large an easily accessible source for paper production. This is because the trees are in high density making them easy to extract and there is a large area to build factories in to turn the wood into pulp and then into paper

Question 104

Explain how exploitation of materials is an indirect threat to the taiga:

Answer 104

Many taiga forests are rich in minerals such as iron ore, gold, copper, and silver. Lots of trees are chopped down to make way for mines and access roads

Question 105

Explain how exploitation of fossil fuels is an indirect threat to the taiga:

Answer 105

Tar sands is earth containing thick, black oil, which can be processed into fossil fuels. Tar sands are found underneath taiga forests. Extraction of the tar sands often involves open pit mining or strip mining - digging up the land surface in strips to get to the sands beneath. This causes large scale deforestation as trees must be cleared to extract the tar sands

Question 106

Explain how HEP (Hydroelectric power) is a direct/indirect threat to the taiga

Answer 106

Many taiga forests contain large rivers. Building dams to generate hydroelectric power floods large areas of land behind the dam

Question 107

Explain how melting permafrost is an indirect impact to the taiga forest

Answer 107

Permafrost melts due to deforestation. Trees provide shade and a cool area beneath them meaning that the permafrost does not melt, without these trees the permafrost melts and infiltrates into the soil. This leaches the soil and increases surface sun off, potentially causing flooding. This can limit the plant growth in the area due to limited nutrients and flooding

Question 108

Explain how a direct impact can lead to an indirect impact in the taiga

Answer 108

Deforestation causes a lack of tree cover and shade, this can cause permafrost to melt and infiltrate into the soil

Question 109

Explain how a direct impact can lead to an indirect impact in the tropical rainforest

Answer 109

Deforestation causes less CO2 to be absorbed from the atmosphere and the commercial farming releases methane into the atmosphere. This can increase climate change and global temperature increase. This can then lead to droughts and natural forest fires

Question 110

Explain 2 impacts of the extraction of tar/oil sands for the environment

Answer 110

• Tar sands are extracted by either deforesting the taiga and strip mining the surface or by steaming the tar out so it melts and can be collected. Either method destroys the forest, and produces toxic waste collected in ponds
• Mining uses 2-4 tonnes of water for every tonne of oil produced, plus natural gas to heat water into steam

Question 111

Explain how forest fires can indirectly affect the taiga biome

Answer 111

Wildfires are a natural part of the ecosystem - they allow net growth and regenerate the forest. However, its thought that climate change is leading to warmer, drier conditions in taiga forests. This is increasing the frequency of fires and making the fire season longer. Forest fires can destroy huge numbers of trees and may change the distribution of species as some species are better at recolonising burnt areas. They may also break forest up into smaller sections, which makes it hard for migratory animals that need a lot of space to find enough food

Question 112

Explain how pests and diseases can indirectly affect the taiga biome

Answer 112

Pests and diseases cause damage to organisms. Many pests and diseases are specific to one species, e.g. Spruce Bark Beetles attack spruce trees. As there is often a single tree species in a particular area in taiga forests, it is easy for the pests and diseases to spread and multiply - they can do a lot of damage. It is thought that warming caused by climate change is making it easier for pests and disease causing pathogens to survive - new pests and diseases are arriving and the frequency of attack is increasing

Question 113

Explain how Acid rain can indirectly affect the taiga biome

Answer 113

Burning fossil fuels releases gases, such as sulphur dioxide and nitrogen oxides. These dissolve in water in the atmosphere to form acids. When it rains or snows, the acids are deposited on plants and soils. Acid rain damages plants’ leaves and makes it harder for them to cope with the cold. It can also make the soils too acidic to support growth and kills organisms in lakes and streams

Question 114

Explain why deforestation in the taiga is less of an issue than in the tropical rainforest

Answer 114

Taiga biomes are extremely large and vast, despite Russian and Canadian deforestation accounting for over 40% of all deforestation between 2000 and 2013, only 8% of intact taiga has been lost. In the tropical rainforest there are many endangered species that are under threat, this is not an issue in taiga forests. Also, much of the taiga is isolated and “out of sight” in the frozen north latitudes

Question 115

Explain why logging can have a direct impact on the loss of nutrients in the taiga forest

Answer 115

In the taiga nutrient cycle, leaf litter is the largest nutrient store, followed by biomass. As trees grow they drop pines which decompose and release nutrients into the soil, these nutrients are then used to help other trees grow. If there is logging in the forest then there will be no trees to release litter and they will not release nutrients back into the nutrient cycle, causing a loss of nutrients. This will in turn make it more difficult for other trees to grow as there is not enough nutrients for them to grow and survive

Question 116

Explain how the taiga forest is threatened both directly and indirectly by human activity

Answer 116

A direct threat from human activity on the taiga forest is deforestation. Humans’ cut down trees and log for softwood for many reasons such as paper production and manufacturing. This reduces the area of the taiga and threatens the wildlife that lives there. This is because it further reduces the already limited biodiversity and destroys habitats for the wildlife. An indirect threat is the melting of permafrost due to deforestation. Trees provide shade and a cool area beneath them meaning that the permafrost does not melt, without these trees the permafrost melts and infiltrates into the soil. This leaches the soil and increases surface sun off, potentially causing flooding. This can limit the plant growth in the area due to limited nutrients and flooding.

Question 117

What is REDD?

Answer 117

REDD is an acronym for “Reduced Emissions from Deforestation and forest Degradation”. It is a scheme that aims to reward forest owners in poorer countries for keeping forests instead of cutting them down

Question 118

What are advantages of the REDD scheme?

Answer 118

• It deals with the cause of climate change as well as direct impacts of deforestation
• The forest is protected so remains a habitat for species - biodiversity is not lost
• Everyone benefits from reducing emissions and it is a relatively cheap option for doing so

Question 119

What are negatives of the REDD scheme?

Answer 119

• Deforestation may continue in another area
• Aspects of REDD are not clear, meaning that it may be possible to cut down forests, but still receive the rewards if they are replaced with other types of forest, e.g. with palm oil plantations, which are low in biodiversity
• Preventing activities, e.g. agriculture and mining, may affect local communities which depend on the income from them

Question 120

What is CITES?

Answer 120

CITES is an acronym for “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

Question 121

What are 2 ways in which the tropical rainforest is being preserved?

Answer 121

The CITES and REDD schemes

Question 122

What are advantages of CITES?

Answer 122

• The issue is tackled at a global level, which means the trade of endangered species is controlled all over the world and not just in a handful of countries
• It raises awareness of threats to biodiversity through education

Question 123

What are disadvantages of CITES?

Answer 123

• Although individual species are protected from poaching but it does not protect their habitat - they could still go extinct, e.g. due to the impacts of climate change
• Some rules are unclear, e.g. on the trade of ivory
• Not all countries are members - some countries even promote the trade of materials from endangered species

Question 124

What economic reasons cause Sustainable forest management to be a challenge?

Answer 124

• The economic benefits of sustainable management are only seen in the long term. This affects poorer countries who need income immediately
• Sustainable forestry is usually more expensive so it can be difficult to persuade private companies to adopt sustainable methods
• Many sustainable forestry schemes are funded by government departments and NGO’s. If the priority of these organisation changes then funding could stop quite quickly

Question 125

What social reasons cause Sustainable forest management to be a challenge?

Answer 125

• Sustainable forest management generally provides fewer jobs for local people than conventional forestry, so many locals wont see the benefits. Some may turn to illegal logging, which is difficult to police
• If the population of a forest area increases, the demand for wood and land from the forest increases. Sustainable forestry is unlikely to provide enough resources to match the increasing demand

Question 126

What Environmental reasons cause Sustainable forest management to be a challenge?

Answer 126

• If trees are replanted, the new forest may not resemble the natural forest - the trees are replaced but the entire ecosystem may not be restored
• Trees that are replanted for logging in the future can be very slow growing - companies may chop down more natural forest whislt they are waiting for the new trees to mature
• even selective logging can damage lots of trees in the process of removing target trees

Question 127

Explain how sustainable Farming offers a long term solution to conserving the rainforest?

Answer 127

Sustainable farming techniques protect the soil so that the land remains productive - there is no need to clear new land every few years. These techniques include:

• Agroforestry - trees and crops are planted at the same time, so that the tree roots bind the soil and the leaves protect it from heavy rain
• Crop rotation - crops are moved between different fields each year with one left empty so the soil has time to recover
• Green manure - Plants which add nutrients to the soil as they grow are planted to maintain soil fertility

Question 128

Explain how ecotourism offers a long term solution to conserving the rainforest?

Answer 128

Ecotourism is tourism that minimises damage to the environment and benefits local people.

• Only a small number of visitors are allowed into an area at a time. Environmental impacts are minimised, e.g. by making sure waste and litter are disposed of properly to prevent land and water contamination.
• Ecotourism provides a source of income for the local people, e.g. they act as guides and provide accommodation and transport.
• It can also raise awareness of conservation issues and bring in more money for rainforest conservation.
• If local people are employed in tourism, they do not have to log or farm to make money, meaning fewer trees are cut down.
• If a country’s economy relies on ecotourism, then there is an incentive to protect the environment

Question 129

What is a wilderness area?

Answer 129

A wilderness area is an area that is undisturbed by human activity that is managed with the aim of protecting the landscape

Question 130

What is a national park?

Answer 130

An area that is mostly in its natural state that is managed to protect biodiversity and promote recreation

Question 131

What is sustainable forestry?

Answer 131

Ways of harvesting the timber from the forest without damaging it

Question 132

What are 3 methods used to conserve the taiga?

Answer 132

• Creating a wilderness area
• Creating a national park
• Sustainable forestry

Question 133

What are the advantages of creating a wilderness area?

Answer 133

Creating a wilderness area has the highest level of protection - most human activity is banned. The area is kept as pristine as possible. It usually covers a very large area so large-scale natural processes can still take place, e.g. migration

Question 134

What are the advantages of creating a national park?

Answer 134

A national park may be established to protect particular species, e.g. wood bison. It often covers a large area. Unsustainable human activity such as logging and mining is not permitted. There is good access for tourists and recreational users

Question 135

What are the advantages of sustainable forestry?

Answer 135

• Limits can be placed on the number of trees felled or the size of clear-cut areas to allow the forest to regenerate.
• Companies may be required to regenerate the area after logging.
• Selective logging means that some trees remain to become part of the new forest

Question 136

What are the disadvantages of creating a wilderness area?

Answer 136

• The large, remote area is difficult to police.
• There is economic pressure on governments who want to use the resources.
• There is pressure from companies and tourists to build roads to allow greater access

Question 137

What are the disadvantages of creating a national park?

Answer 137

National parks must take into account the needs of indigenous communities, who may use the land for hunting etc. Tourism may be required to pay for the conservation, but access roads, infrastructure, and pollution from tourists can harm the ecosystem.

Question 138

What are the disadvantages of sustainable forestry?

Answer 138

Some countries struggle to enforce the restrictions, e.g. Russia - lots of illegal logging takes place. There may be a lack of clear management or information about the ecosystem. Different groups may not agree with the rules and restrictions, e.g. indigenous people, loggers, government, environmentalists

Question 139

Explain the point of view of people who think the taiga should be protected

Answer 139

• Taiga forests store lots of carbon - deforestation will release some of this as CO2, which causes global warming
• Some species are only found in the taiga. Because they are adapted to the conditions, the destruction of the habitat could lead to their extinction
• Many indigenous people, e.g. the Sami people of Scandinavia, depend on the forest for their traditional way of life

Question 140

Explain the point of view of people who think the taiga should be exploited

Answer 140

• The demand for resources is increasing - people need the wood, fuel, and minerals that the forest provides
• Forest industries, e.g. logging and mining, provide a lot of jobs (e.g. forestry and logging employ 25,000 people in Canada)
• The exploitation of the forest generates a lot of wealth for the countries involved (e.g. the forestry industry in Sweden is word nearly US$15 billion each year)

Question 141

What is sustainable forest management?

Answer 141

Sustainable forest management is when the forest is used in a way that prevents long-term damage, whilst allowing people to benefit from the resources it provides in the present and in the future

Question 142

What factors are causing a loss of biodiversity in the taiga?

Answer 142

• Exploitation of resources
• Acid rain
• Pests and disease
• Forest Fires