Unit 4 - Biodiversity within a community

Question 1

What is biodiversity?

Answer 1

A measure of the variety of living organisms within a particular habitat

Question 2

Definition of Species diversity

Answer 2

Refers to the number of different species and the number of individuals of each species within any one community

Question 3

Definition of Genetic Diversity

Answer 3

The number of different alleles of genes within a population

Question 4

Definition of Ecosystem diversity

Answer 4

The range of different habitats from a small local habitat to the whole of the earth.

Question 5

Definition of species richness

Answer 5

A measure of the number of different species in a community

Question 6

Definition of Index of diversity

Answer 6

Describes the relationship between the number of species in a community and the number of individuals in each species

Question 7

How to calculate index of diversity

Answer 7

N(N-1)
d = ———-
En(n-1)

N = total number of organisms of all species 
n = total number of organisms of each species

Question 8

Processes that have directly removed habitats and reduced species diversity

Answer 8

• Removal of hedgerows and grubbing out woodland
• Creating monoculture, eg replacing natural meadrows
  and cereal crops of grass for silage
• Filling in ponds and draining marshland and other
  wetland
• Over grazing of land preventing regeneration of
  woodland

Question 9

Other practices that have had a more indirect effect (Farming on environment)

Answer 9

• Use of pesticides and inorganic fertiliser
• Escape of effluent from silage stores and slurry
  tanks into water courses
• No crop rotation

Question 10

Examples of conservation techniques

Answer 10

• Maintain existing hedgerows - beneficial height and
  shape
• Plant hedgerows rather then erect fences as field
  boundaries
• Maintain existing ponds
  -reduce use of pesticides and use biological controls
  instead