Cambridge IGCSE Environmental Management: Ecosystems, Biodiversity and Fieldwork — Practice Questions (0680)

These questions test all of Topic 5, Ecosystems, biodiversity and fieldwork, in Cambridge IGCSE Environmental Management (0680, 2027-2029). They move from definitions to energy calculations, a mangrove case and a fieldwork investigation of the kind set on Paper 2, Environmental Management in Context.

These are original questions written for Marlbridge, for revision and practice on this content. They are not reproduced past-paper questions, and they do not replicate the exam’s exact structure, question count or mark tariffs — Cambridge International holds copyright in its own papers. Use these alongside the official past papers available free from your board.

Related: Ecosystems study guide and revision notes

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Section A

1. Define niche. [1]

2. State three abiotic components of a freshwater ecosystem. [3]

3. Write the word equation for photosynthesis. [2]

4. State what is meant by an invasive species. [1]

Section B

5. A food chain in a mangrove forest is: mangrove leaves → crabs → fish → herons

(a) Identify the secondary consumer. [1] (b) The mangrove leaves fix 50 000 kJ of energy. Calculate the energy reaching the herons, assuming 10% transfer at each level. [2] (c) Explain why energy is lost between trophic levels. [3] (d) Explain why a pyramid of numbers for this chain might not be pyramid-shaped, whereas a pyramid of energy always is. [3]

6. Describe how wind pollination leads to the formation of seeds. [3]

7. Describe how carbon moves from the atmosphere into a fish and back again. [4]

8. Mangrove forest along a coast is cleared for shrimp farms and a new road. (a) Describe three impacts of this deforestation. [3] (b) Explain two reasons why the mangroves should be managed sustainably. [4]

9. Define sustainable management of forests. [2]

10. A student investigates whether the number of plant species changes with distance from a footpath across a field. (a) Suggest a hypothesis. [1] (b) Identify the independent and dependent variables. [2] (c) Describe how the student could use a transect and quadrats to collect the data. [4] (d) The student records one quadrat with 19 species where the others nearby have 4-6. Suggest how this anomaly should be dealt with. [2]

11. Name the sampling technique most suitable for each: (a) beetles active on the ground at night; (b) insects in tall grass; (c) the area of forest lost over a large region. [3]

Section C

12. Discuss the benefits and limitations of random and systematic sampling for measuring the population of a plant species. [6]

13. Discuss the benefits and limitations of national parks and of zoos with captive breeding as ways to conserve endangered species. [6]

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Answers

1. The role of a species in its ecosystem. [1]

2. Any three: temperature; water; oxygen; carbon dioxide; salinity; light; pH. [3]

3. carbon dioxide + water → glucose + oxygen. [2] (1 for reactants, 1 for products.)

4. A species that is not native to an area and has been introduced, which can spread and harm native species. [1]

5. (a) Fish. [1] (b) 50 000 → 5 000 (crabs) → 500 (fish) → 50 kJ (herons). [2] (c) Energy is used in movement [1] and respiration [1]; some is lost in digestion and excretion and is not passed on [1]. (d) Numbers depend on organism size: one mangrove tree supports many crabs, so the bottom bar may be narrow [1]; energy decreases at every level because about 90% is lost [1], so each bar of an energy pyramid is always smaller than the one below [1].

6. Pollen is carried by wind from an anther [1] to a stigma of a flower [1]; this leads to fertilisation, followed by seed and fruit formation [1].

7. Carbon dioxide is taken in by plants or algae in photosynthesis [1]; it becomes glucose and other carbon compounds [1]; the fish eats the plants or smaller animals (feeding) [1]; carbon returns to the atmosphere as carbon dioxide through the fish’s respiration or decomposition after death [1].

8. (a) Any three: habitat loss for crabs, fish and birds [1]; loss of biodiversity [1]; soil erosion [1]; silting and flooding [1]; global warming from released carbon [1]; genetic depletion. [max 3] (b) Any two explained: mangroves are carbon sinks and stores, so keeping them limits global warming [2]; they protect against flooding and erosion of the coast [2]; they provide food and raw materials, such as fish nurseries and wood, for local people [2]; they offer ecotourism and education [2]. [max 4]

9. Balancing the needs of the environment, wildlife and humans [1] while conserving forests for future generations [1].

10. (a) The number of plant species increases with distance from the footpath. [1] (b) Independent: distance from the path [1]; dependent: number of plant species [1]. (c) Lay a tape measure at right angles to the path [1]; place a quadrat at regular intervals, such as every 2 m (systematic sampling) [1]; count the different species in each quadrat [1]; repeat with further transects to improve reliability [1]. (d) Check the identification or recount if possible [1]; otherwise exclude it from the mean and note it, or repeat the sample at that point [1].

11. (a) Pitfall trap [1]; (b) sweep net [1]; (c) aerial photography, satellite images or drones [1].

12. [6] Random: avoids bias because every point has an equal chance [1]; suits a uniform area [1]; but may leave parts unsampled by chance [1]. Systematic: covers the area evenly and shows change along a gradient, such as from a path [1]; easy to carry out [1]; but may miss or exaggerate patterns that coincide with the sample interval [1]. Credit a conclusion that the choice depends on the aim.

13. [6] National parks: benefit - protect whole habitats and many species at once, and can fund themselves through ecotourism; limitation - need guards and funding, poaching may continue, local people may lose land. Zoos and captive breeding: benefit - can save species with very small populations and educate visitors; limitation - expensive, small gene pool, and animals may not survive release if their habitat is gone. Conclusion: in-situ protection is usually needed for long-term success, with captive breeding as a back-up.

A note on exam technique for this topic

In fieldwork questions, link each step to reliability or accuracy. “Repeat” earns a mark only with a reason, such as allowing a mean to be calculated. In energy questions, show each trophic level so method marks are not lost.

Frequently asked questions

Do I need to name flower parts? No. The 0680 syllabus states that knowledge of the structure and naming of flower parts is not required; only the anther-to-stigma transfer.

How do I identify an anomaly? It is a result that does not fit the pattern of the others. Suggest checking or repeating it, and explain whether it is excluded from the mean.

Which energy figure should I use? Use 10% transfer between trophic levels unless the question gives different data.

Official syllabus

Cambridge IGCSE Environmental Management (0680) syllabus for 2027, 2028 and 2029 - official syllabus PDF.