Ecologists investigate the distribution of one species of moss on heathland. Water from a spring enters the heathland at one edge.
The ecologists take pilot measurements of soil moisture.
| Distance from the spring edge in m | 0 | 4 | 8 | 12 | 16 | 20 |
|---|---|---|---|---|---|---|
| Soil moisture in % | 72 | 65 | 57 | 49 | 40 | 33 |
Suggest how the ecologists should sample the moss to investigate how its distribution changes with distance from the spring.
The ecologists find that the abundance of the moss decreases with distance from the spring. A student concludes that the fall in soil moisture causes the fall in moss abundance.
Explain why the results do not prove this conclusion.
109 exam-style questions on OCR GCSE Biology 6.1 Monitoring and maintaining the environment, covering 6.1.1 Field investigation of distribution and abundance, 6.1.2 Human interactions and biodiversity, 6.1.3 Maintaining biodiversity, and 6.1.4 Environmental change and distribution of organisms. Each one has a worked solution and a mark scheme showing where the marks go.