Forests Under Threat

Question 1

What is biotic ?

Answer 1

Living component of a rainforest

Question 2

What is abiotic?

Answer 2

Non living components

Question 3

Biotic and abiotic are closely related. If one changes the others are affected. Give an example.

Answer 3

Agouti (rodent) are one of only animals who crack open the hard seed pod of the Brazil nut to eat the nut. Sometimes, agouti bury the nut - these can sprout into new seedlings. If agouti become extinct, brazil nut trees would decline and so could all the other animals who live in or feed on the Brazil nut trees. People who sell them are also affected

Another example : Warm and went climate means that plant grows quickly. The dense leaf cover protects the forest floor from wind + heavy rainfall, while root systems hold the soil together - this stops it being eroded.

Question 4

Name the tropical rainforest layered structure in order.

Answer 4

Emergents
Main Canopy
Under canopy
Shrub Layer

Question 5

How is emergents adapted to the hot, wet climate?

Answer 5

Tallest trees, have straight trunks and only have branches and leaves at the top where they can get light. Have buttress roots to support their trunks.

Question 6

How is main canopy adapted to the hot, wet climate?

Answer 6

Continuos layer of trees. They have leaves at the top. Dense layers of leaves shades the rest of the forest.

Question 7

How is the under canopy adapted to the hot, wet climate?

Answer 7

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

Question 8

How is the shrub layer adapted to the hot, wet climate?

Answer 8

Nearest to ground where it’s quite dark. Shrubs have large, broad leaves to absorb as much of the available light as they can.

Question 9

What other adaptations do plants have?

Answer 9

Plants have thick, waxy leaves with pointed tips. Drip tips channel the water to a point so it runs off.

Many trees have smooth, thin bark as there is no need to protect the trunk from cold temperatures. Smooth surface also allows water to run off easily.

Plants drop their leaves gradually throughout the year, meaning they can go growing all year around.

Question 10

How are animals adapted to the physical conditions?

Answer 10

Many animals spend their entire lives high up in the canopy. They have strong limbs so they can spend all day climbing/leaping

Some are camouflaged

Many rainforest animals can swim. Allows the to cross river channels.

Question 11

What is a nutrient cycle?

Answer 11

The way nutrients move through an ecosystem

Question 12

What are the three ways nutrients are stored in the ecosystem?

Answer 12

• living organisms (biomass)
• dead organic material
• the soil

Question 13

Most nutrients are stored as biomass and the transfer of nutrients is very rapid. This is because:

Answer 13

1) Trees are evergreen, so dead leaves and other material fall all year round.
2) The warm + moist climate means that fungi and bacteria decompose the dead organic matter quickly. Nutrients released are soluble and are soaked up by the soil.
3) dense vegetation and rapid plant growth mean that nutrients are rapidly taken up by plants’ roots.

Question 14

What is biodiversity?

Answer 14

The variety of organisms living in a particular area - both plants and animals.

Question 15

Do rainforests have high biodiversity?

Answer 15

Yes, they contain 50% of the worlds plant, animal and insect species.

Question 16

Why do rainforests have high biodiversity?

Answer 16

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

Rainforests are stable environments - it’s hot and wet all year round. They are also very productive 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 they are able to specialise

Question 17

Why do rainforests have complex food webs?

Answer 17

There are so many different species that there are loads and loads of links

Some animals can be both primary and secondary consumers

Question 18

What is the order of a food chain?

Answer 18

Producer - plants
Primary consumer - fruit bats and insects
Secondary consumer - snakes
Tertiary consumer - crocodiles and jaguars

Question 19

Deforestation is a direct threat to tropical rainforests. What are some of the reasons why areas of tropical rainforests are destroyed?

Answer 19

Local demand for fuel wood - local people chop down trees to use as fuel for cooking or to burn to make charcoal

Mineral resources - minerals are often found in tropical rainforests

Electricity (HEP) - many tropical rainforests have large rivers. Building dams to generate hydroelectric power floods large areas of forest behind the dams.

Commercial logging - trees are felled to make furniture and for construction. Road building for logging also requires more tree clearance

Commercial farming - forest cleared to make space for cattle grazing

Subsistence farming - forest cleared so farmers can grow food for themselves and their families

Question 20

What environmental impacts does deforestation have?

Answer 20

With no trees to hold the soil together, heavy rain washes it away. This can lead to landslides and flooding,

Trees remove Co2 from the atmosphere. Also, burning vegetation to clear forest produces Co2. Deforestation means more Co2 in the atmosphere, which adds to greenhouse effect

Question 21

Why is climate change a threat to tropical rainforests?

Answer 21

Some areas temperature is increasing and rainfall is decreasing, which leads to drought. Droughts lead to ecosystem stress - plants and animals are adapted to moist conditions so may die in dry conditions. Frequent or long periods of drought could lead to extinction of some species.
Drought can also lead to forest fire which can destroy large areas of forest.

Question 22

Why is deforestation increasing in some parts of the world?

Answer 22

Poverty - population growth and poverty mean there are many more small - scale subsistence farmers.

Foreign debt - huge market for goods from tropical rainforests, so it’s am easy way for poor countries to make money to pay back the debt they owe to richer countries.

Economic development - road and rail projects to promote development open up areas of the rainforest to logging, mining and farming

Question 23

Why is deforestation decreasing in some parts of the world?

Answer 23

Government policies - eg Costa Rican government has invested in ecotourism and pays landowner to reforest areas.

International condemnation - puts pressure on companies by naming and shaming those involved in deforestation.

Monitoring systems - Global Forest Watch provides satellite data to track forest loss. This means authorities can act more quickly to stop illegal logging.

Question 24

REDD (Reduced Emissions from deforestation and forest degradation) is a global action to protect tropical rainforests what is its overview?

Answer 24

A scheme that aims to reward forest owners in poorer countries for keeping forest instead of cutting them down.

Question 25

What is an advantage of REDD.

Answer 25

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 its a relatively cheap option

Question 26

What is a disadvantage of REDD.

Answer 26

Deforestation many continue in other areas.

Aspects of REDD are unclear, meaning that it may be possible to cut down rainforests, but still receive rewards is they are replaced with other types of forest e.g palm oil which is low on biodiversity

Question 27

CITIES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) is a global action to protect tropical rainforests what is its overview?

Answer 27

An agreement to tightly control trade in wild animals and plants.

Question 28

What is an advantage of CITIES?

Answer 28

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

Raise awareness of threats to biodiversity through education.

Question 29

What is a disadvantage of CITIES?

Answer 29

Some rules are unclear

Not all countries are members.

Question 30

What are the economic challenges involved in a successful sustainable forest management?

Answer 30

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.

Question 31

What are the environmental challenges involved in a successful sustainable forest management?

Answer 31

If trees are replanted, the new forest may not resemble the natural forest.

Trees that are replanted for logging in the future can be very slow growing - companies may chop down more natural forest whilst they are waiting for new trees to mature

Question 32

What are the social challenges involved in a successful sustainable forest management?

Answer 32

Generally provide fewer jobs for local people than conventional forestry, so many locals won’t see the benefits. Some may turn to illegal logging, which is difficult to police.

Question 33

Alternative livelihoods might be a better long term option. Name some alternative ways.

Answer 33

Ecotourism - minimises damage to the environment and benefits local people

Sustainable Farming - techniques protect the soil so that the land remains productive - there is no need to clear new land every few years

Question 34

Taiga forests are interdependent ecosystems. What is meant by interdependent?

Answer 34

All parts of the taiga forests are dependent on one another - if any one of them changes, everything else is affected.

Question 35

Give an example of interdependent ecosystem.

Answer 35

Plants gain nutrients from the soil, and provide nutrients to the animals that eat them. In turn, animals spread seed through their dung, helping the plants to reproduce.

The cold climate causes plants to grow slowly and also to decompose very slowly. Meaning that the soil is relatively low in nutrients - further reducing the ability of plants to grow.

Question 36

How are plants adapted to cool, dry climate in Taiga Forests?

Answer 36

They are evergreen - so they can make best use of the available light.

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

Cone shaped - heavy winter falls can slide off.

Question 37

How are animals adapted to cool, dry climate in Taiga Forests?

Answer 37

They are well insulated against the winter cold.

Some animals hibernate