Biodiversity

Question 1

What is a species?

Answer 1

• A group of individual organisms that are similar in appearance, anatomy, biochemistry and genetics
• Members are able to interbreed freely to produce fertile offspring

Question 2

What is a habitat?

Answer 2

• Place where an organism lives
• Specific locality with a specific set of conditions
• Organisms are well adapted to their habitats

Question 3

What is biodiversity?

Answer 3

• The variety of living organisms
• Degree of nature’s variety
• Allows for permanent stability of an ecosystem
• Involves an equilibrium between species

Question 4

3 levels which biodiversity can be considered on

Answer 4

• Habitat
• Species
• Genetic

Question 5

What is habitat biodiversity?

Answer 5

• Range of habitats
• Within a habitat or a community
• Diverse habitats can lead to diverse species
• Essential to conserve them

Question 6

What is species biodiversity?

Answer 6

• Difference between species - within habitat or community
• Difference can be structural or physical
• Can collect data about different species
  (Species richness and evenness)

Question 7

What is genetic biodiversity?

Answer 7

• Exists within a species
• Degree of allelic variation between members of a species
• Lack of variation results in lack of ability to adapt
• Natural selection depends on variation

Question 8

Calculating genetic diversity

Answer 8

Calculate % of loci in a population with more than one allele
Formula :
genetic diversity = number of polymorphic gene loci/ total number of loci x100

Question 9

Human factors affecting biodiversity

Answer 9

• Hunting for food
• Over harvesting
• Killing for protection/removal of competitors for food
• Pollution
• Habitat destruction
• Population growth
• New predators to flora and fauna

Question 10

Consequences of climate change

Answer 10

• Migrations
• Disease
• Agriculture

Question 11

What is species richness?

Answer 11

• Number of species present in a habitat
• More species present, richer the habitat
• Does not count the number of individuals of each species

Question 12

What is species evenness?

Answer 12

• The number of individuals of each species
• Relative to population size
• Relative abundance of each species
• Habitat of even number of species is likely to be more diverse than dormant species
• Quantitative survey is carried out

Question 13

Survey frequency of plants

Answer 13

• Count number of each species present in sample area
• Smaller plants is easier to calculate percentage cover

Question 14

How does migration affect biodiversity?

Answer 14

• Loss of genetic variation
• Reduction in gene pool
• Decrease genetic variation, limit ability to evolve
• Unable to adapt to changing environment
• Only alternative is them to move
• Animals in protective areas may be forced out for survival

Question 15

How does agriculture affect biodiversity?

Answer 15

• High C02, temp and increasing growth rates
• Longer growing seasons
• Greater evaporation and precipitation
• Loss of land due to sea level rising
• Domesticated plants have little variation therefore at greater risk
• Farmers find yields decreasing (forced to change crops, climate change

Question 16

How does disease affect biodiversity?

Answer 16

• Crops grown in new areas will encounter new pests
• May not be resistant to new pests
• Pest population may increase due to longer growing periods
• Human diseases thrive most in moist tropics, migrate to poles
• Cause spread of disease

Question 17

How does population growth affect biodiversity?

Answer 17

• Destroy habitats to support own agriculture needs
• Alter ecosystems to provide settlement and food
  (Reduction by reducing suitable habitat)
• More people = more carbon dioxide

Question 18

Maintaining biodiversity for moral reasons

Answer 18

• Last living members of species will die if not maintained
• 784 recorded extinctions since 1500
• Spread of humans mean extinction rate has risen for other species
• Extinction primarily caused because of human activity

Question 19

Benefits of having large biodiversity

Answer 19

• Extinction reduced biodiversity
• Human clearing of land for agriculture reduces habitats rise in extinction
• Monoculture of plants
• Genetic erosion reduces biodiversity
• Prevent organisms from adapting to survive in changes in environment

Question 20

Economic and ecological reasons to maintain biodiversity

Answer 20

• Nature provide us with future developments
• Help with technological problems
• Regulate the atmosphere
• Purify fresh water
• Recycle nutrients
• Crop pollination
• Growth in timber, food and fuel

Question 21

Aesthetic reasons to maintain biodiversity

Answer 21

• All organisms have the right to live
• Loss of habitat may displace organisms
• Humans feel joy from observing nature
• Natural systems are very important for physical, social, mental health

Question 22

Other reasons why we should maintain biodiversity?

Answer 22

• Allow genetic diversity to decline, may lose natural solution to problems
• Nature is a potential source for new medicines
• Nature may be the solution to problems (transgenic species, survive climate change)

Question 23

Difference between in situ and ex situ methods

Answer 23

In situ : supporting natural ecosystems in the wild (within)
Ex situ : Moving endangered species into man-made environments

Question 24

In situ methods - Minimise human impact on environment

Answer 24

• Legislation (prevent human activities, may only be specific to one area)
• Conservation Parks (permanent protection,conflict arise if animals escape)
• Repopulation ( rebuilding biodiversity, costly, unknown impact on environment)

Question 25

Ex Situ methods : risk disturbance to natural environment

Answer 25

- Zoos ( lowers likelihood of extinction, not kept in natural environment) - Seed Bank (Have infinite options for future use, storage needs to be controlled, seed germination + viability needs to be tested annually)

Question 26

Simpson's Index of Biodiversity

Answer 26

- Takes richness and evenness into account - Gives an idea of number of each species relative to population size - Small and large populations treated differently

Question 27

High index of biodiversity means...

Answer 27

- Diverse habitat - Many species live there - Small change to environment may only affect one species - Total effect on habitat is small, tends to be stable habitat

Question 28

Low index of biodiversity means...

Answer 28

- Suggest it is dominated by few species - Small change to the environment may affect one of the major species - Could damage or destroy the whole species - Small change have large impact on environment - Much less stable environment

Question 29

Ways to sample animals

Answer 29

- Sampling may disturb the habitat - Animals may be frightened away - unrepresentative sample - Swamp netting, collecting from trees, pitfall trap. tullgren funnel, light trap Estimate after they have been caught

Question 30

How to sample plants?

Answer 30

- Square frame quadrat , define sample area - Abundance measured (ACFOR abundance scale, estimate % cover, key to identify species)

Question 31

ACFOR abundance scale

Answer 31

A : Abundant C : Common F : Frequent O : Occasional R : Rare

Question 32

What is sampling? What does it allow us to do?

Answer 32

- When a small, random portion of a habitat is selected and studies carefully - Allows us to see impacts on environment, estimate effects of a planned development on the environment

Question 33

Random Samples

Answer 33

- Must be chosen randomly - Avoid bias/subjectivity - Estimate size of the habitat and decide where to take samples