4.6 Biodiversity within a community

Question 1

Define biodiversity:

Answer 1

The variety of living organisms in an area

Question 2

What are the 3 components of biodiversity?

Answer 2

1. Species diversity – the number of different species and the number of individuals of each species within a community
2. Genetic diversity
3. Ecosystem diversity

Question 3

Define habitat:

Answer 3

Places where an organism lives

Question 4

Define community:

Answer 4

All the populations of different species in a habitat

Question 5

What is local biodiversity?

Answer 5

The variety of species living in a small habitat e.g. pond / meadow

Question 6

What is global diversity?

Answer 6

The variety of species living on Earth

Question 7

What is global diversity?

Answer 7

The variety of species living on Earth

Question 8

What is species richness:

Answer 8

The number of different species in a community

Question 9

How do you measure index of diversity?

Answer 9

D / N(N-1)/Σn(n-1)

Question 10

The greater the species richness and species evenness…

Answer 10

The higher the number (index of diversity)

Question 11

Why is index of biodiversity a more useful measure of species diversity than species richness?

Answer 11

• As well as measuring the number of species, it also measures the number of individuals in a species (different proportions of species)
• So takes account for the fact that some species may be present in low/high numbers

Question 12

What farming techniques that reduce biodiversity?

Answer 12

• Removal of woodland and hedgerows
• Monoculture e.g. replace natural meadows with one cereal crop
• Use of pesticides, herbicides and inorganic fertilisers
• Crops better competitors for resources e.g. light / nutrients