4.2

Question 1

Define biodiversity.

Answer 1

Measure of variation found in the living world

Question 2

Define habitat.

Answer 2

Where an organism lives

Question 3

Define species.

Answer 3

a group of organisms that can freely interbreed to produce fertile offspring

Question 4

How is random sampling carried out?

Answer 4

• sample sites inside habitat randomly selected

- random selection through computer generated co ordinates

Question 5

Advantage of random sampling?

Answer 5

• Data is not bias

Question 6

Disadvantages of random sampling?

Answer 6

• May not cover all areas

- Species with low presence may be missed leading to underestimate of biodiversity

Question 7

How is opportunistic (non-random) sampling carried out?

Answer 7

• Sample decisions made using prior knowledge or during data collection
• May sample area where particular species can be seen

Question 8

Advantages of opportunistic (non-random) sampling?

Answer 8

• Easier and quicker then random sampling.

Question 9

Disadvantages of opportunistic (non-random) sampling?

Answer 9

• Bias -> colourful area

- Overestimate of biodiversity due to overestimate of importance

Question 10

How is stratified sampling (non-random) carried out?

Answer 10

• Divide habitat in equal sized areas which appear different

- Sample separately

Question 11

What are the advantages of stratified sampling (non-random)?

Answer 11

• All habitat samples

- Species not under represented

Question 12

Disadvantage of stratified sampling?

Answer 12

• Possible over representation

Question 13

How is systematic sampling carried out?

Answer 13

• Sample taken at intervals

- Line or belt transect used

Question 14

Advantages of systematic sampling?

Answer 14

• Useful when clear gradient in habitat

Question 15

Disadvantage of systematic sampling?

Answer 15

• Only species on line or within belt sampled leading to possible underestimation of biodiversity

Question 16

How do you sample invertebrates?

Answer 16

• Sweep net through vegetation in wide arcs
• Net will capture insects
• Empty net on white sheet
• Pooter in case they fly away
• Suitable for low vegetation

Question 17

How to collect samples from trees?

Answer 17

• Place white sheet under the tree
• Hit branches with stout stick
• Vibrations will dislodge small animals causing them to fall on white sheet
• Count and identify samples

Question 18

How does a pitfull trap work?

Answer 18

• Container set in soil with rim underneath the surface
• Insect falls into container
• Little water and scrunched paper to avoid crawling away
• Rainy conditions should have shelter

Question 19

How does tullgren funnel work?

Answer 19

• Leaf litter in funnel
• Light bulb drys up and heats leaf litter
• Insects move downwards falling through mesh into a jar

Question 20

How does light trap work?

Answer 20

• Collects fly’s at night
• Vessel underneath containing alcohol will collect fly’s
• Ultraviolet used

Question 21

How does logworth trap work?

Answer 21

• MAR technique
• Humane way
  1) Capture sample of animals
  2) Make each individual and record as C1
  3) Release back into environment, set trap for a period of time
  4) New captured animals recorded as C2
  5) Re-captured animals marked as C3
  6) Total population = (C1 x C2) / C3

Question 22

What are the limitations of logworth trap?

Answer 22

• Animals may come again as a