Measuring biodiversityAQA A-Level Biology: Mind map

Exam questions on Measuring biodiversity

1. Two ponds were each surveyed with the same sampling effort. Each pond contained four species and 100 individuals in total. In pond A the individuals were shared equally between the four species. In pond B, one species made up 97 of the individuals and each of the other three species was represented by a single individual.
   Explain why species richness alone is not a sufficient measure of the biodiversity of the two ponds.2 marks
2. An ecologist calculated the index of diversity (d) for ground beetles in two habitats. The value for a hedgerow was 1.8 and the value for an area of ancient woodland was 14.5.
   Suggest why the community in the woodland is likely to be more stable than the community in the hedgerow when the environment changes.2 marks
3. A survey of ground beetles in a woodland used randomly placed pitfall traps and recorded five species, with 12, 8, 5, 3 and 2 individuals of each. A sample collected in the same way in a neighbouring conifer plantation contained three species, with 25, 4 and 1 individuals of each.
   Calculate the index of diversity (d) for the woodland sample, using $d = \frac{N(N-1)}{\sum n(n-1)}$. Show your working.3 marks