Ecologists studying peatland restoration use an empirical formula to estimate the depth of the water table (in cm below the surface) based on the species diversity of soil micro-organisms:
Estimated depth (cm)=(mean number of testate amoebae species per 10 cm3)×4.25+8.6 \text{Estimated depth (cm)} = (\text{mean number of testate amoebae species per } 10\text{ cm}^3) \times 4.25 + 8.6 Estimated depth (cm)=(mean number of testate amoebae species per 10 cm3)×4.25+8.6The table below shows the data collected from five different restoration plots:
| Plot | Mean number of testate amoebae species per 10 cm310\text{ cm}^310 cm3 |
|---|---|
| Alpha | 3.2 |
| Beta | 5.6 |
| Gamma | 4.8 |
| Delta | 7.4 |
| Epsilon | 6.1 |
Calculate the estimated water table depth in Plot Gamma.
67 exam-style questions on OCR GCSE Biology 4.1 Ecosystems, covering 4.1.1 Cycling of materials in ecosystems, 4.1.2 Microorganisms in cycling materials, 4.1.3 The carbon and water cycles, 4.1.4 Factors affecting decomposition, 4.1.5 Levels of organisation in an ecosystem, 4.1.6 Abiotic and biotic factors affecting communities, 4.1.7 Interdependence and competition, 4.1.8 Trophic levels, 4.1.9 Pyramids of biomass, and 4.1.10 Efficiency of biomass transfers. Each one has a worked solution and a mark scheme showing where the marks go.