3.4.6 Biodiversity

Question 1

What is biodiversity

Answer 1

Variety of living things

Question 2

Different ways that biodiversity can be considered

Answer 2

Genetic diversity - variety of alleles of different genes within a population.
Species diversity - no of different species in a community and number of individuals of each species
Ecosystem diversity - range of habitats

Question 3

What is the index of diversity

Answer 3

• ways of quantifying species biodiversity
• comparing both the species richness and species evenness in different community

Question 4

Simpson’s index

Answer 4

d = N(N-1) / En(n-1)

Where N = total number of organisms of all species
And n = number of individuals in each species

Question 5

Causes of reduced species diversity

Answer 5

• herbicides
• rapid growth of crops & clearing area for crop growth
• monoculture
• reduced ecosystem diversity

Question 6

Causes of reduced ecosystem diversity

Answer 6

• draining the land
• filling ponds
• removing hedgerows
• grazing
• reducing the diversity of plants, fewer food sources and habitats / nesting sites for animals, so animal diversity reduced

Question 7

Conservation measures include:

Answer 7

Increasing ecosystem diversity:
- replanting / maintaining hedgerows
- digging ponds
- producing hay from natural meadows

Increasing opportunities for species diversity
- biological control rather than pesticides
- crop rotations
- natural fertilisers