An ecological study investigates the relationship between the volume of distinct marine reef sectors and the age of their primary coral structures. The age of a primary structure can be estimated using the mean species richness index, SSS, of the sector using the following formula:
Age (years)=S×18+50 \text{Age (years)} = S \times 18 + 50 Age (years)=S×18+50where S S\,S is the mean species richness index per cubic meter.
The scientists recorded data for five distinct reef sectors, as shown in the table below:
| Sector | Volume of Sector (m3\text{m}^3m3) | Mean species richness index (SSS) |
|---|---|---|
| P | 450 | 3.5 |
| Q | 150 | 5.4 |
| R | 800 | 2.2 |
| S | 300 | 4.5 |
| T | 1200 | 1.3 |
Calculate the estimated age of the primary structures in Sector S.
Modern marine conservation policies often prioritize larger reef sectors. Does the data support the claim that older primary structures tend to be located in smaller sectors? Explain your answer with reference to the calculated ages or indices of the largest and smallest sectors.
111 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.