Biodiversity

Question 1

What is biodiversity?

Answer 1

• variety of living organisms in an area, inc species diversity, genetic diversity + ecosystem diversity

Question 2

What is species diversity?

Answer 2

• NO° of diff species + NO° of individuals of each species within a community

Question 3

What is species richness?

Answer 3

• NO° of diff species in a community

Question 4

What is genetic diversity?

Answer 4

• NO° of diff alleles of genes in a population

Question 5

What is index of diversity?

Answer 5

• measure of species diversity, describing relationship between NO° of species in a community + NO° of individuals in each species

Question 6

How do you calculate index of diversity (d)?

Answer 6

d = N(N-1)/Σn(n-1)
- N = total NO° of organisms
- n = total NO° of individuals of each species

Question 7

What farming techniques reduce biodiversity?

Answer 7

• destruction of hedgerows
• selective breeding
• monocultures
• over grazing
• ponds filled in + wetlands drained

Question 8

How does destruction of hedgerows dec biodiversity?

Answer 8

• bc hedgerows provide habitat for insects + small birds + animals

Question 9

How does selective breeding dec biodiversity?

Answer 9

• organisms w desirable characteristics are selected to reproduce, ensuring these characteristics are expressed in future gens
• narrows down gene pool, dec diversity

Question 10

How do monocultures dec biodiversity?

Answer 10

• only 1 type of crop species grown
• dec diversity bc attracts same insects that feed on it

Question 11

How does over-grazing dec biodiversity?

Answer 11

• livestock left to overgraze, so dec plant species affecting food web

Question 12

How does draining wetlands dec biodiversity?

Answer 12

• removes habitats for aquatic species to provide space for farming

Question 13

What are the compromises between conservation + farming?

Answer 13

• remove only a certain NO° of hedgerows
• only selectively breed in a particular area + to particular species
• crop rotations for monocultures

Question 14

What is a niche?

Answer 14

• role of a species within its ecosystem, inc its habitat + interactions w biotic + abiotic factors

Question 15

Describe the method used for random sampling.

Answer 15

• lie 2 tape measures at a right angle to form a coordinate grid (big so is representative of area)
• use a random NO° generator to generate random coordinates
• place quadrat + collect data (NO° of individuals of species)
• repeat many times + calculate mean

Question 16

Describe the method used for systematic sampling.

Answer 16

• stretch a tape measure across area along envi gradient being studied
• place a quadrat at regular intervals along line (e.g. every 2m)
• collect data (NO° of individuals of species)
• use data to observe how species distribution changes along transect