# A conservation team is comparing the biodiversity of two woodland sites, Site A and Site B. Site A is an ancient semi-natural woodland with a wide variety of tree species, ground flora, insects and fungi. Site B is a recently planted commercial conifer plantation with a single tree species and very little ground flora. Explain why Site A has greater biodiversity than Site B, using the concept of species richness and species evenness in your answer.

> OCR A-Level Biology A (H420) — 4.2 Biodiversity · Explain · 4 marks

> Site A: ancient semi-natural woodland containing 24 different plant species, 61 invertebrate species and 15 fungal species, with no single species dominating. Site B: commercial conifer plantation containing 1 tree species and 4 invertebrate species, with the conifer accounting for over 95% of all individual organisms recorded.

## Mark scheme (4 marks)

1. Site A has greater species richness than Site B
2. Site A has greater species evenness than Site B
3. Greater variety of plant species in Site A provides more ecological niches / habitats
4. The monoculture in Site B reduces habitat diversity, limiting the species that can survive there

## Key terms

- [biodiversity](https://www.gradenine.co.uk/glossary/biodiversity)
- [species richness](https://www.gradenine.co.uk/glossary/species-richness)
- [species evenness](https://www.gradenine.co.uk/glossary/species-evenness)

## Related

- [Revision notes for OCR A-Level Biology A (H420)](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-conservation-team-is-comparing-the-e8ecbc78) · Published by Druglandscape Ltd.