Exam-style Questions: Ecosystems

  1. a) Describe the effects of tropical storms.

    (3 Marks)

    b) Why are the effects of droughts worse in LEDC's than MEDC's?

    (4 Marks)

    c) What are the consequences of drought in LEDC's?

    (4 Marks)

    (Marks available: 11)

    Answer

    Answer outline and marking scheme for question: 1

    a) Give yourself marks if you mentioned any of the following points:

    • Deciduous forest/coniferous forests/dense shrub land.
    • Oaks and pines/maquis/garrigue.

    (3 marks)

    b) Give yourself 1 - 2 marks if you mention the following points:

    • Waxy leaves/long roots/fire resistant.

    Give yourself 3 - 4 marks if you can expand the above points:

    • Waxy leaves prevent water loss.
    • Long roots reach water found deep below the surface.
    • Small trees and shrubs are fire resistant.
    • Rosemary rolls up its leaves to reduce moisture loss.
    • Thick bark protects against the heat.

    (4 marks)

    c) Give yourself marks if you mentioned any of the following points:

    • Much woodland has been cleared for fuel and building materials.
    • Areas have been cleared for farming.
    • Topsoil containing nutrients is washed away.
    • Grazing has caused damage to shrub land.
    • Fires have destroyed woodland.
    • Soil left infertile.

    (4 marks)

    (Marks available: 11)

  2. Which of the statements below are true and which are false?

    a) Soils in the tropical rainforest are very fertile.

    b) Soils in the tropical rainforests are called brown earths.

    c) Soils in the tropical rainforest have a thick humus layer.

    (3 Marks)

    d) Describe how humans use the tropical rainforest.

    (6 marks)

    e) Explain how the vegetation in the tropical rainforests have adapted to the climate.

    (3 marks)

    (Marks available: 12)

    Answer

    Answer outline and marking scheme for question: 2

    a) False.

    b) False.

    c) True.

    (3 marks)

    d) Give yourself 1 - 2 marks if you mentioned the following points:

    • Logging/ranching/damning.
    • Subsistence farming/mining.

    Give yourself 3 - 4 marks if you expanded the above points:

    • Large-scale forest clearence has taken place for cattle ranching.
    • Dams are built to provide power for industries.
    • Areas along the sides of roads have been cleared for subsistence farming.

    Give yourself 5 - 6 marks if you can write about the uses in depth and give case studies:

    • The Carajas project set up in the tropical rainforests in Brazil mines iron ore.
    • The Tucurui Dam was built in the northern rainforests of Brazil to provide power for mines and papermills in the area.

    (6 marks)

    e) Give yourself marks if you mentioned the following points:

    • Wide shallow roots collect the water in the top layer of the soil.
    • Leaves are found at the top of trees to best use the light.
    • Buttress roots stop the trees toppling over.
    • Leaves have drip tips to allow rainfall to fall quickly.

    (3 marks)

    (Marks available: 12)

  3. Which of the statements below are true and which are false?

    a) Podsols are acidic soils.

    b) Podsol soils have many earthworms.

    c) Earthworms mix the soil.

    (3 marks)

    d) Describe the climate found in areas where there are coniferous (Boreal) woodlands.

    (3 marks)

    e) Describe the soils found in deserts.

    (2 marks)

    f) Explain how desert vegetation has adapted to the climate.

    (4 marks)

    (Marks available: 12)

    Answer

    Answer outline and marking scheme for question: 3

    a) True.

    b) False.

    c) True.

    (3 marks)

    d) Give yourself marks if you mentioned the following points:

    • Warm summers/very cold winters/half the year below 0oC.
    • Summer temperatures between 12-18oC/low annual rainfall.
    • Snow in winter/rain mainly in summer.

    (3 marks)

    e) Give yourself marks if you mentioned any of the following points:

    • Alkaline/very dry/little humus/not infertile.

    (2 marks)

    f) Give yourself marks if you mentioned any of the following points:

    • Waxy skin and spikey leaves reduce transpiration.
    • Thick stems store water.
    • Deep roots get underground water.
    • Roots close to surface to collect rainfall.
    • Plants widely space to collect the maximum amount of rainfall.
    • Seeds only germinate when the rain come.

    (4 marks)

    (Marks available: 12)

  4. a) Explain why deforestation can reduce soil fertility.

    (3 Marks)

    b) How can deforestation affect people who live in these areas?

    (4 Marks)

    c) Describe how tropical rainforests can be managed.

    (3 Marks)

    (Marks available: 10)

    Answer

    Answer outline and marking scheme for question: 4

    a) Give yourself marks if you mentioned the following points:

    • Humus is not replaced.
    • Nutrients are washed away downwards.
    • Leaves do not fall to create humus.
    • The vegetation creates most of the nutrients.

    (3 marks)

    b) Give yourself 1 - 2 marks if you mentioned the following points:

    • Increased flooding/homes lost/moved to urban areas.
    • Created jobs.

    Give yourself 3 - 4 marks if you can expand any of the above points. You may also use case studies:

    • Increased surface runoff due to deforestation can cause increased flooding, which can lead to the destruction of infrastructure.
    • Homes of native groups of people living in the forests can be lost.
    • As the soil becomes less fertile farmers in North and Central Brazil have moved to shanty towns, like Rochina, in urban areas.
    • The Carajas mining project has created 2000 jobs.

    (4 marks)

    c) Give yourself marks if you mentioned the following points:

    • Sustainable development.
    • Replacing the same amount of trees as you remove.
    • Create more National Parks where deforestation cannot occur.
    • Reduce the mass burning of trees.

    You may also gain marks for using relevant case studies.

    (3 marks)

    (Marks available: 10
    )