# A farmer grows the same crop in the same field every year without adding fertilisers. After several years, the crop yield decreases significantly. Explain why the crop yield decreases and state two elements that a fertiliser would need to supply to restore the soil.

> Cambridge International IGCSE Chemistry (0620) — 10.2 Fertilisers · Explain · 4 marks

## Mark scheme (4 marks)

1. Plants absorb / remove mineral ions (nutrients) from the soil as they grow
2. Repeated cropping means minerals are not replaced / soil becomes deficient in minerals
3. First correct element named (nitrogen / phosphorus / potassium)
4. Second correct element named, different from the first (nitrogen / phosphorus / potassium)

## Key terms

- [fertiliser](https://www.gradenine.co.uk/glossary/fertiliser)
- [crop yield](https://www.gradenine.co.uk/glossary/crop-yield)

## Related

- [Revision notes for Cambridge International IGCSE Chemistry (0620)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-farmer-grows-the-same-crop-6c8476b9) · Published by Druglandscape Ltd.