Populations in Ecosystems - Sampling Techniques

Question 1

abundance

Answer 1

number of individuals

Question 2

2 ways of measuring abundance of animals

Answer 2

mark, release, recapture
kick sampling

Question 3

how to measure abundanceof plants

Answer 3

quadrats

Question 4

3 measurements using quadrats

Answer 4

1. countig individuals to calculate density
2. estimate % cover
3. estimate % frequency

Question 5

when would you use % cover?

Answer 5

when you can’t distinguish individuals

Question 6

5 assumtions of MRR

Answer 6

1. there are few biths/deaths
2. there’s no migration
3. proportion of marked:unmarked is same proportion in whole population
4. marked individuals distibute themselves evenly
5. method of marking isn’t toxic, lost, rubbed off or making them more conspicous

Question 7

distribution of a species

Answer 7

the area or volume in which the species is found

Question 8

2 things needed to measure distribution of plants

Answer 8

tape measure (2) and quadrat

Question 9

3 things to consider when choosing a quadrat

Answer 9

1. size (determined by size of species)
2. number (minimum 20)
3. positioning (systematic or random)

Question 10

when would you place quadrats systematically?

Answer 10

in a non-uniform habitat

Question 11

3 steps of random sampling using quadrats

Answer 11

1. set up axes with 2 tape measures
2. random number generator for 2 coordinates
3. measure abundance

Question 12

2 steps of using a belt transect

Answer 12

1. place quadrats at regular intervals along tansect
2. measure abundance

Question 13

how to use a line transect?

Answer 13

count individualswhich touch the line or tape measure

Question 14

4 ways to summarise and draw conclusions from data?

Answer 14

1. mean
2. range
3. SD
4. diversity index

Question 15

biodiversity

Answer 15

the number of different species and the number of individuals i each populations

Question 16

how to calculate diversity index

Answer 16

(N(N-1))/(Σ n(n-1))

Question 17

when is a kite diagram useful? (2 things)

Answer 17

1. when diffiult to distinguish b/w individuals and % cover is easier to measure
2. when different species are different sizes, it gives a better comparison

Question 18

what does a kite diagram show us about competition

Answer 18

shows where species are competing and who is winning