Tropical Rainforests

Question 1

Where are tropical rainforests found?

Answer 1

Deserts are located in the Tropics, the Tropic of Cancer and the Tropic of Capricorn, 30° north and south of the Equator. They are located on every continent except from Antarctica. The largest desert is the Sahara, and it covers 11 countries, including Egypt, Morocco, Niger, Mali, Chad, Sudan, Eritrea and Mauritania.

Question 2

What is the soil profile like in the tropical rainforest?

Answer 2

The O Horizon (humus layer, usually formed of decomposing animals, litter and leaves) is very thin. This is because the material decomposes very fast in the tropical climate. The A Horizon (buildup of humus which has decayed) is very large, as the leaf litter is abundant, and it breaks down easily. There is no B Horizon (sturdy soil, made up of clay) in the tropical rainforest, and this makes it loose and vulnerable to washing away. The C Horizon (rock) and the bedrock are thin layers also.

Question 3

What do the different layers of soil do in a tropical rainforest?

Answer 3

The A Horizon is made up of decayed material low in minerals and nutrients, and does not support plant life. The O Horizon is washed away easily by rainstorms that occur almost every day. The rainforest depends on the soil for its nutrients, and this is called the nutrient cycle.

Question 4

What are some examples of interdependence in the rainforest?

Answer 4

The Brazil Nut Tree depends on the agouti to scatter its seeds, and the tree gives the agouti shade and shelter, as well as a place to live.

Question 5

What is the forest floor of a rainforest like?

Answer 5

The forest floor gets around 2% of light. The height of this layer is from 0 - 5m, and many insects live here, as well as jaguars, gorillas, humans, pumas and snakes. There is no grass here, and it is the most humid part of the rainforest. The underlying soil is hidden by a thin layer of rotting leaves. Fungi and termites decompose this layer.

Question 6

What is the shrub layer of a rainforest like?

Answer 6

The shrub layer goes from 5 - 20m above the ground and it is the layer with the densest plant growth, where there are shrubs, saplings and ferns. It receives about 25% of light.

Question 7

What is the understorey layer of a rainforest like?

Answer 7

The understorey goes from 15 - 20m above the ground. It is dark, meaning that there aren’t many plants, however ferns, mosses, vines, insects and birds live here. It gets around 50% of light.

Question 8

What is the canopy layer of a rainforest like?

Answer 8

The canopy goes from 20 - 30m above the ground, around receives around 75% of light. There are birds, insects, arachnids, reptiles, mammals, possums and vines all living here.

Question 9

What is the emergent layer of the rainforest like?

Answer 9

This layer is full of very tall trees, stretching 35 - 40m into the air. The conditions are very windy, and hot, however macaws, monkeys and insects live here. This layer gets 100% of light.

Question 10

How has the spider monkey adapted to living in the rainforest?

Answer 10

The spider monkey can grow up to 2 feet, and they have a powerful tail which they use as an extra limb. They hang upside down from tree branches, which makes them look like a spider. They can swing from branch to branch at high speeds, and spend most time in the canopy.

Question 11

How has the toucan adapted to living in the rainforest?

Answer 11

Toucans have large and colourful bills, which helps them to attract mates. It is also very lightweight, and their calls are harsh and raspy. The toucan’s bill is sharp and has saw like edges, which they use to tear fruits off trees. They eat smaller birds, reptiles and lizards.

Question 12

How has the fan plant adapted to living in the rainforest?

Answer 12

Fan palms have large, fan shaped leaves that are good at catching sunshine and water. Their leaves are segmented, meaning excess water can drain away. The fan shape also provides shade.

Question 13

How has the liana adapted to living in the rainforest?

Answer 13

Lianas are woody vines that start at ground level, and use the trees to climb up to the canopy, where they spread from tree to tree, to get as much light as possible. They bury their roots deep within the ground, meaning they have a stable base. Many lianas grow to 200m, and supports weaker trees in heavy wind and rain.

Question 14

What is deforestation?

Answer 14

Deforestation is the process in which natural forest is cleared through burning and cutting the trees for both commercial and private uses. 36 football fields a minute of rainforest are cut down.

Question 15

What are the impacts of deforestation?

Answer 15

Reduced biodiversity, as animals lose their habitat, and 50% of the world’s plant and animal species are found in the rainforest. Greenhouse gases are also produced, and deforestation accounts for 15% of the global greenhouse gases that are produced. Trees can no longer absorb water from the soil, meaning the water cycle is disrupted. This can make the climate drier. Increased soil erosion also takes place, as the trees no longer hold the soil in place.

Question 16

What are the causes of soil erosion?

Answer 16

Compaction is where the soil becomes squashed because there is no vegetation to protect it. The loss of soil structure means that the layers in the soil profile are disrupted, and the nutrient cycle becomes ineffective. As trees are cut down, there is no longer any leaf litter to provide nutrients. When the water evaporates, lots of salt is left behind, killing crops and plants.

Question 17

Why is palm oil a cause of deforestation?

Answer 17

Palm trees produce red fruits which have a very high yield of oil. Palm oil is used for makeup, chocolate and biodiesel. A single hectare can produce 7 tonnes of oil. It is a good alternative to fossil fuels. However, the increase in palm oil production is linked to the decrease in rainforest cover. For example, in Indonesia, in 1964, there was no palm oil produced, but 120 million hectares of forest, and in 2006 there was 16.1 million tonnes of palm oil produced, and 80 million hectares of forest.

Question 18

Why is road building a cause of deforestation?

Answer 18

Roads have to be constructed to provide access to mining areas. In the Amazon Rainforest, 30,000 miles of rainforest was cut down for roads. Around 10,000 miles of roads were built in Brazil each year from 2004 to 2007. The Trans - Amazonian Highway in Brazil is 5,300 km long and has destroyed many habitats.

Question 19

Why is subsistence farming a cause of deforestation?

Answer 19

One of the methods used in subsistence farming is called slash and burn. It makes the soil unfertile, as much of it washes away in the rain, it can be sustainable, provided that the trees are given long enough to grow back, but it often isn’t. Slash and burn makes up 70% of all deforestation, and makes up 17% of the world’s greenhouse gases. This technique is used by 300 million people worldwide, and it was estimated 500,000 small farmers were clearing a hectare a year through this method.

Question 20

Why is logging a cause of deforestation?

Answer 20

Malaysia is described as “mega diverse” by Conservation International and its rainforests host around 20% of the world’s species. However, Malaysia had the highest rate of forest loss in the world between 2000 and 2012. 30% of the Congo has been allocated for logging, and 90% of Malaysia’s lowland forests have been allocated as well. Only $8 million is being earned by the Malaysian government from logging, 12 cents per person.

Question 21

Can logging be a good thing?

Answer 21

It can be, because the World Bank suggests that the logging industry could create 300,000 new jobs in Malaysia. If 1 - 2 million cubic metres of timber were sold, Malaysia could generate $200 - 400 million from this.

Question 22

Why is mineral extraction a cause of deforestation?

Answer 22

Yasuni National Park in Ecuador has over 20 endangered mammals in it. The Ecuadorian government said it wouldn’t drill for oil there, as long as they got $3.6 billion, but they only received $13 million. In Malaysia, annual output of bauxite ore has increased to 20 million tonnes. It is strip mined, however Malaysia only has 10 years worth of the reserves left. The noise affects residents and a broken pipeline spilled 400,000 gallons of oil into the Coca River. This left 65,000 people without water.

Question 23

Can mineral extraction be a good thing?

Answer 23

Malaysia is now the world’s top producer of bauxite, and it accounts for half of the supplies to the Chinese aluminium industry. The project in the Yasuni National Park in Ecuador will help to stop poverty, and will generate around $7 billion for the country. By 2019, Ecuador hopes to extract a quarter of a million barrels per day.

Question 24

Why is energy development a cause of deforestation?

Answer 24

The Bakun Dam in Sarawak, at 205m, is Asia’s highest dam outside China. The dam’s reservoir flooded over 700 square kilometres of forest and farmland. They account for 5% of total deforestation. However, people have to be displaced and wildlife can be killed. The dams can get clogged with silt, which makes them useless, and they can reduce flow downstream which affects farmers. The standing water in the reservoirs can also cause malaria.

Question 25

Can energy development be a good thing?

Answer 25

The demand for energy in Malaysia is steadily increasing, as in 1970, there was around 4 thousand gigawatts of demand, and in 2010 there was 100 thousand gigawatts of demand. The hydroelectric power plants also provide jobs to people.

Question 26

Why is population growth a cause of deforestation?

Answer 26

There is a strong relationship between countries with large population growth and the amount of forest that is lost through deforestation. In Malaysia, poor urban people were encouraged by the government to move into the countryside from the cities, and this is called transmigration. Between 1956 and the 1980s, around 15,000 hectares of forest was felled for the settlers, who set up plantations.

Question 27

Why is cattle farming a cause of deforestation?

Answer 27

The global demand for beef is growing because the population is increasing, and more people are becoming wealthier so they can afford to eat meat more often. The Yanomami are an isolated tribe in Brazil. More than 1,000 ranchers are working on the Yanomami's land, illegally, transmitting diseases like malaria and polluting the rivers and forests. Cattle ranchers are deforesting their land, and they use the roads they have built as an access point to chop down more.

Question 28

What are the overall positives of the oil industry?

Answer 28

250,000 jobs have been created, and the oil sector accounts for around 50% of Ecuador's export earnings, and 1/3 of their tax revenues. They have oil reserves of 7.2 billion barrels, worth $8 billion. It has increased local employment and has enhanced infrastructure.

Question 29

What are the overall negatives of the oil industry?

Answer 29

Social inequality has become more obvious, and health workers have reported problems like skin conditions and cancers, believed to be caused by exposure to dangerous chemicals. Oil operations have discharged 4.3 million gallons of toxic waste into the Oriente's environment each day. Toxic contamination in drinking water has reached 1000x the safe standard. Before the oil operations started, Ecuador was debt free, however the external debt is $16 billion, 80% of their GDP.

Question 30

What is sustainable management?

Answer 30

It involves conserving the ecosystems for future generations, and making sure it isn't used faster than it can be reused. Local people need to make sure the ecosystem still provides them with resources, and schemes that educate local people, and help them make decisions can be set up. Sustainable schemes allow people to make a profit from eco - tourism. It also involves being environmentally friendly, and encourages selective logging.

Question 31

What is the culture in the rainforest like?

Answer 31

The Congo Basin has been inhabited by humans for more than 50,000 years. It is home to 75 million people, and nearly 150 different ethnic groups. 500 years ago, an estimated 10 million Indians lived in the Amazon, but now, only 1 million survive. They are divided into 400 tribes.

Question 32

What is the biodiversity in the rainforest like?

Answer 32

More than half of the world's 10 million species of plants, animals and insects live in tropical rainforests. The Amazon biome spans 6.7 million square kilometres, and houses 10% of the world's biodiversity.

Question 33

What are medical innovations from the rainforest like?

Answer 33

Digitalis, a medicine to treat heart failure, comes from the rainforest, which comes from the foxglove plant. Currently, over 120 drugs comes from plant derived sources, and of 3,000 plants found good for cancer treatments, 70% are in the tropical rainforest. There are around 10,000 species of plants in the Congo, and 30% are unique to the region. However, deforestation has destroyed over hundreds of unique species of plants.

Question 34

What are the resources from the rainforest like?

Answer 34

Due to deforestation, the Earth loses an estimated 137 plant, animal and insect species each day, and the tropical rainforest could be all gone within 40 years. 25% of our medicines come from the tropical rainforest, but only 1% of the materials have been tested. The world has 80% of its dietary items come from the rainforest, like oranges, lemons, grapes, avocados, figs, sugar cane, rice, coconuts and squash.

Question 35

What is the carbon cycle?

Answer 35

During the carbon cycle, plants, during photosynthesis, absorb carbon dioxide from the atmosphere. When a plant respires, dies or burns, the carbon dioxide within the plant is released into the environment. It is released into rivers, where it becomes fossil fuels, which animals breathe in. When the animal dies, it is released, and the process starts again. The rainforest absorbs 2.2 billion tonnes of carbon dioxide each year, however when forests are burned or cleared 30 - 60% of this carbon dioxide is released to the atmosphere.

Question 36

What is the water cycle?

Answer 36

The water cycle is where the trees intercept the daily heavy convectional rain, and absorb it. Some of the rain reaches the ground, and the trees take up water from the ground. The water then evaporates, or transpires. This constant process means that the Congo Rainforest releases 190,000 litres of water each year.

Question 37

What is agroforestry?

Answer 37

This is where trees and crops are grown at the same time. The farmers take advantage of the shelter from the canopy of the trees, and the crops benefit from the nutrients of dead forest matter. In the Amazon Rainforest, in Brazil, farmers use this method for cocoa, guava and avocado plantations.

Question 38

What is the impact of agroforestry?

Answer 38

It tries to preserve the nutrient recycling system, and allows both parties to benefit, because the trees are not cut down, and the farmers' crops get shade and nutrients. The soil does not wash away due to a lack of trees and the same land can be used multiple times.

Question 39

What is re - planting?

Answer 39

Replanting is where local people living in the rainforest help to replant trees in areas where deforestation has happened. Charity Save The Orangutan has been working in Rantau Upak, in Borneo, to educate the locals on the importance of replanting.

Question 40

What is the impact of re - planting?

Answer 40

Save The Orangutan estimates that, in the last four or five years, they would have planted 100,000 trees in the villages in Borneo. They have also managed to make Rantau Upak a permanent protected area. The trees that are chosen have been specially picked to encourage endangered species to come back to the area.

Question 41

What is conservation?

Answer 41

The act of conservation is to try and protect the rainforest, before it is completely ruined. Forest is quite cheap to buy, as the Rainforest Trust bought 11,000 acres of the rainforest, at $4 an acre. Charity Cool Earth also encourages people to donate to save an area of the forest.

Question 42

What is the impact of conservation?

Answer 42

The Rainforest Trust protected the Sierra de las Minas Biosphere Reserve, and this protects an important watershed in the rainforest. Conserved places can also be used for tourism, as well as for scientific research.

Question 43

What is debt reduction?

Answer 43

Debt reduction is where a debt owed to another country is reduced, and this is done through conservation projects. The US and Brazil has signed an agreement worth $13.5 million, and this will help Brazil to conserve its Atlantic coastal rainforest. The USA and Guatemala have also struck a $24 million deal.

Question 44

What is the impact of debt reduction?

Answer 44

The US has signed deals with 16 countries, and this means that countries who may have not had enough money to conserve the rainforest before, now do. Both sides benefit, the rainforest, and the country.

Question 45

What is eco - tourism?

Answer 45

Eco - tourism is a sustainable way for locals to make money. It could taking people on tours around the rainforest. At Volcanoes in Rwanda, local people are given the option to build a lodge on their land, which the locals could then rent out to tourists. This means that they can benefit tourists, as well as themselves, as they make a profit, as well as protecting the rainforest.