Sampling

Question 1

What is a quadrat used for?

Answer 1

Quadrats are square frames that can be used to:

• Estimate population sizes
• To observe how changing conditions will effect a population of a species.

Question 2

What can a transect be used to investigate?

Answer 2

-The effect of a factor of distribution on a species.

Question 3

What is a transect line and how is it used?

Answer 3

• A piece of tape that is stretched across the habitat of interest.
• Quadrats are placed together at regular intervals at the transect line.

Question 4

What is quantitive data?

Answer 4

Specific- involves maths e.g. 60 percent.

Question 5

What is the method used to estimate population?

Answer 5

1. Randomly select 3 quadrat areas and count the amount in each.
2. Calculate the total and then divide by the number of samples to find the mean.
3. Multiply the mean by the number of quadrats in the field to get an estimate for the amount of the whole thing.

Question 6

How do you find the number of quadrats in a field?

Answer 6

Area of field/ area of quadrat

Question 7

How do you measure the effect of change in the environment on a population?

Answer 7

1. Place the transect across the sample area.
2. Use quadrats to estimate population size at regular intervals across the transect.
3. Plot continues.

Question 8

Describe how you would use a 1/2 metre x 1/2 metre quadrat frame and a 30 metre tape measure ?

Answer 8

• I would use the tape measure to produce a transect.
• I would randomly chose 3 areas to place the quadrats, making sure the quadrat is used at regular intervals along the tape.
• I would count the things of interest inside the quadrats.
• I would repeat the transect several times.