Living World – 9 The Value of the Tropical Rainforest

●Watch the video below for a recap from this unit and a reminder what will be covered this week from Mr Price at BMA who is leading this lesson.

Specification points covered in this blog

Why should tropical rainforests be protected?

In our last blog we looked at the impact of deforestation, the process of removing trees for other purposes, such as cattle ranching, mining or hydro-electric power production. It was clear to see that whilst the deforestation did create some economic and social advantages, the impact on the environment was and is devastating.

In today’s blog we will consider the reasons why rainforests should be protected from further deforestation. It will look at how the rainforest is worth more to us left as it is, than cut down for economic gain in developing nations. Task: Start by watching the video clip below, and then attempting the questions.

Questions:
1. How much of the planet’s freshwater is found in the Amazon?
2. What is the animal they spot up a tree near the start of the clip?
3. From the blog post a couple of weeks ago – can you remember an adaptation of this animal?
4. How many species of fish are found in the Amazon river?
5. How high was the water level when the river floods?
6. How much of the world’s oxygen is produced in the Amazon?
7. What percentage of tropical plants have been tested for their medicinal properties?

Click below for answers:

Answers:

  1. 2/3rds
  2. A sloth
  3. Slow moving / camouflage / nocturnal
  4. 2,000
  5. 9 metres
  6. 20%
  7. Less than 1% (!)

Study the inforgraphic below about how medicines derive from plants in the rainforest:

Task: Look at the infographic above and use it to answer the questions. Click to reveal the answers.
1) How any prescription drugs come from rainforest plants?
2) What proportion of all drugs with cancer fighting properties come from the rainforest?
3) What can vampire bat saliva be used to treat?
4) What can be used to help treat HIV?
  1. 120
  2. 2/3rds
  3. Heart attacks
  4. Secretions from frogs

Goods vs Services

Medicine from plants in the forest is an example of the rainforests providing ‘goods’. These are physically products that can be taken and used, often for economic profit.

Services are harder to measure as they often do not have a financial value. An example of a ‘service’ provided by the rainforest is that it helps to purify the atmosphere by removing carbon dioxide.

Below are a selection of ‘goods’ and ‘services’ provided by the rainforest:

Goods and services card sort
  • Task: a. Go through the statements above and decide whether or not you think it is a ‘good’ or a ‘service’ provided by the rainforest. b. Pick 2 ‘goods’ and 2 ‘services’ from the list and explain the benefits and value of what is being provided.

The three most important and most valuable services provided by the rainforest, are vital for the health of the entire globe. They are: 1. Regulating the composition of the atmosphere (carbon dioxide and oxygen) 2. Regulating the water cycle 3. Maintaining soil health in the rainforest

Below are three images of the above ‘services’. The first image shows how carbon and oxygen are regulated by the trees and animals. The second image is a very simplified version of the water cycle acting in the rainforest, and finally, and image of the nutrient cycle – whereby ‘biomass’ is the trees in the rainforest.

Task: Use the diagram of the water cycle, and your own wider knowledge – fill in the blanks below using the following key words:

Water: In the Amazon rainforest is usually rains every afternoon. South-Easterly winds blow moisture-laden air in off the _______________________. This water is combined with the water vapour that has _______________________ off leaves or is being released from the plant through________________________. The warm air rises during the morning and then cools during the afternoon leading to condensation and rainfall. Much of this water is _________________by the leaves on the trees and then the cycle begins again.

Missing words answers:
  1. Atlantic
  2. evaporated
  3. transpiration
  4. interception

Task to finish:
Based on everything you have covered in this blog and the last, write a response to the following statement. Back up your response with examples, and try to consider both sides of the arguement.

‘The rainforest is worth more when it is left intact than when it is destroyed.’

Extension:

Watch the video below, up to 4 minutes. Then answer the questions below:

1. Why is the Amazon often called the ‘lungs’?
2. How do the trees cause the winds which help the water cycle?
3. How much carbon dioxide is taken out of the atmosphere by the Amazon rainforest?
  1. The trees in the rainforest exchange oxygen and carbon dioxide through the process of photosynthesis.
  2. Through the process of transpiration/evapotranspiration.
  3. 1 trillion tonnes

Some activities and images used have been resourced from GCSE Geography AQA -Simon Ross, Nicholas Rowles, David Holmes, Bob Digby. Published by Oxford.