4.2.2 Sampling to Determine Biodiversity Flashcards
1
Q
Why sample?
A
Measure distribution and abundance of species in an area
2
Q
When do we randomly sample?
A
When there seems to be no patterns in the data, and to avoid bias to fairly represent the data for that area
3
Q
What is a quadrat good for?
A
Good for randomly sampling plants or slow moving animals
4
Q
Methods of random sampling?
A
- Sweeping nets (catch insects in air or grass)
- Pitfall traps (catches ground dwelling insects or invertebrates)
- Pooters (place tube over insect, suck through other end, insect falls into container)
5
Q
What are methods of non-random sampling?
A
- Opportunistic
- Stratified
- Systematic
6
Q
Opportunistic Sampling notes
A
- Picking and choosing sampling locations
- Based off non-random factors
- Eg. Safest sampling locations coz kids are on a field trip
7
Q
Stratified sampling notes
A
- Matching number of sampling locations in a particular habitat
- With relative proportion of area that that habitat covers in the whole area studied
- Eg. If an area contains 10% woodland and 90% grassland, of 100 samples, 10 would be in the woodland habitat and 90 in the grassland habitat
8
Q
Systematic Sampling notes
A
- Where there is a clear change in the physical conditions across the area studied
- Eg. Changes in altitude, soil pH, light intensity
- Using transects is good for this
- A transect line is a measuring tape along which samples are taken
- At equal distances along line
- Record identities of organisms that touch the line. Produces QUALITATIVE data
- (for a belt transect place quadrats at equal intervals and record abundance / percentage cover of each species within quadrat. Produces QUANTITIVE data)
