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Pearson Edexcel GCSE (9-1) Geography B (1GB0) · Spec 8.1, 8.3 and 8.5

Forests under threat: tropical rainforests

Read the notes, then try the questions. Each one is marked the moment you press Check, and shows the right answer and why.

Key ideas

  • The layers from the top are emergent, canopy, under-canopy, shrub and forest floor. Emergent trees can reach about 45 to 55 metres.
  • Most nutrients are held in the biomass and recycled fast from leaf litter. Heavy rain washes nutrients out of the soil, so the soil itself is poor.
  • When forest is cleared, the nutrient store is removed and the soil quickly becomes infertile.
  • Threats include cattle ranching, farming, logging, mining and dams.
  • Protection includes national parks, sustainable logging and ecotourism. International schemes such as REDD give advice and some money but are voluntary and small compared with the value of the resources.

Key terms

Biomass
The total mass of living plants and animals. In a rainforest it holds most of the nutrients.
Leaching
Heavy rain washing nutrients down through the soil.
Deforestation
Cutting down forest on a large scale.
Canopy
The dense roof of leaves, below the tallest trees.
Biodiversity
The variety of living things in an area.

Common mistakes

  • Saying rainforest soil is deep and fertile. It is nutrient-poor.
  • Saying the rainforest is more biodiverse just because it has a better climate. Say what the climate does: a 12-month growing season and fast nutrient cycling support many niches.
  • Saying global schemes such as REDD pay countries in full to leave the forest alone. They do not.

Exam tip

Section B of Paper 3 is worth about 8 to 12 marks and includes 4-mark Explain two questions. Paper 3 has no 3-mark questions, so the marks come in 1, 2, 4, 8 and 12. Explain two needs two different ideas, each developed. Use the resource booklet figure when the question names it.

Free practice questions

7 questions, 13 marks. Answer, then press Check. The marking guide explains how the marks are worked out. Nothing is saved.

  1. Question 1 · Multiple choice[1 mark]

    Which organisms form the base of a rainforest food web?

  2. Question 2 · Sort into groups[3 marks]

    Sort each part of an ecosystem into the correct group.

    Fox

    Fungi

    Rainfall

  3. Question 3 · Fill the gaps[2 marks]

    Plants make food using energy from the ___, while ___ break down dead matter and return nutrients to the soil.

    Word bank: water · decomposers · sunlight · predators

  4. Question 4 · Put in order[1 mark]

    Put the rainforest layers in order, starting with the tallest.

    Use the arrows to put these in the right order, first at the top.

    1. 1Canopy
    2. 2Under-canopy
    3. 3Emergent layer
    4. 4Shrub layer
  5. Question 5 · Multiple choice[1 mark]

    Which statement about rainforest soil is correct?

  6. Question 6 · Choose more than one[2 marks]

    Which TWO are major causes of deforestation in the Amazon?

    Choose 2.

  7. Question 7 · True or false[3 marks]

    Decide whether each statement about rainforests is true or false.

    1. Rainforest soils are very fertile.

    2. Most nutrients are held in the biomass and recycled quickly.

    3. Emergent trees can reach about 45-55 m.