Sampling (CP 10)

Question 1

State the two sampling techniques that can be carried out in an ecological study

Answer 1

Random and systematic

Question 2

State how to determine which method is appropriate based on the area of study

Question 3

Devise and valid and reliable method for carrying out systematic sampling

Answer 3

1. Lay out a transect (tape measure) along the environmental gradient
   (you may need to stipulate the length of transect)
2. Place a minimum of 10 quadrats down alongside the transect at regular intervals e.g. every 1 metre
3. Collect both relevant and valid abiotic and biotic data at sampling sites (you will need to be specific to the context of the q here, i.e. are you asked about % cover or species richness, what abiotic factors are relevant? You might need to say HOW you estimate % cover)
4. Place down another 2 parallel transects and repeat steps 1-3
5. Record data in a table (IV is the abiotic data and DV is the biotic
   data)
6. Analysis of data can be done using Spearman’s rank which analyses if there is a significant correlation between the abiotic and biotic data

Question 4

Devise a valid and reliable study for carrying out random sampling

Answer 4

In each sampling site, lay out a defined area for sampling using two tape measures (you may need to stipulate the size of area)
2. Use random co-ordinate generator to select sampling sites
3. Lay down a minimum of 10 quadrats in each area
4. Collect both relevant and valid abiotic and biotic data at randomly chosen sites (you will need to be specific to the context of the q here, i.e. are you asked about % cover or species richness, what abiotic factors are relevant? You might need to say HOW you estimate % cover)
5. Record the data in a table (IV is the abiotic data and DV is the biotic data)
6. Analysis of data can be done using Student t-test which analyses if there is a significant difference in the mean % cover/% frequency/species richness (depending on what you have been asked to devise) between the two areas

Question 5

Explain how a frame quadrat can be used to estimate how percentage cover of species

Answer 5

Number of squares that have species in it times by the percentage of a singular square in the quadrat

Question 6

Explain how a quadrat can be used to calculate species richness

Answer 6

Count all the different species within the quadrat and record number