Biodiversity within a community Flashcards – AQA A-Level Biology - (7402)

What is biodiversity?

The variety of living organisms in an area.

At what spatial scales can biodiversity be considered?

From a small local habitat to the whole Earth.

What is species richness in a community?

The number of different species present.

What does species richness not describe about a community?

How individuals are distributed among the species.

What two features of a community does an index of diversity take into account?

Species richness and how evenly individuals are distributed among the species.

What is the formula for the index of diversity $d$, and what do its variables represent?

$d = \frac{N(N - 1)}{\sum n(n - 1)}$

$N$ is the total number of organisms of all species; $n$ is the number of organisms of each species.

What does a greater index of diversity indicate?

Greater diversity.

How can farming techniques reduce biodiversity?

By removing or altering habitats and reducing populations of organisms that live in or use farmland.

How can intensive farm management affect the variety of organisms present?

It can favour a limited range of organisms over a more varied community.

What does biodiversity conservation seek to maintain?

Habitats and species.

What trade-off is involved in balancing biodiversity conservation with farming?

The benefits of protecting biodiversity must be weighed against the land, resources and management needed to produce food and remain economically viable.