Required Practicals - Field investigations

Question 1

What is the goal of the field investigations practical?

Answer 1

To measure the population size of a common species in a habitat using varying sampling techniques to investigate the effect of a factor on its distribution.

Question 2

What is the apparatus for the random sampling field investigation practical?

Answer 2

A quadrat and a metre ruler.

Question 3

What is the method for the random sampling field investigation practical?

Answer 3

-Lay out a grid for the quadrats, numbering it.
-Then randomly select coordinates to position the quadrat
-For each measurement count the number of desired plant
-If a plant is more than half inside the quadrat, count it in your estimate.
-Repeat and calculate a mean
-Calculate the population size by counting the number of plantains counted multiplied by total area/area sampled.

Question 4

What is the apparatus for the transect sampling field investigation practical?

Answer 4

-a quadrat
-a 30m tape measure
-a light meter

Question 5

What is the goal of the transect sampling field investigation practical?

Answer 5

To investigate the effect of light intensity on plant distribution using a transect line.

Question 6

What is the method for the transect line field investigation practical?

Answer 6

-Put the 30m tape measure in a line from the base of a tree to an open area of ground
-Put the quadrat against the transect line. One corner of the quadrat should touch the 0m mark on the tape measure.
-Count the number of plants inside the quadrat.
-Use the light meter to measure the light intensity at this position.
-Record your results in a table.
-Move the quadrat 2m up the transect line and count the number of plants again and the light intensity at this position.
-Continue placing them at 2m intervals and record results in a table.

Question 7

How do you calculate coordinates for random sampling?

Answer 7

Using a random number generator

Question 8

What is the equation for total population size in the random sampling required practical!

Answer 8

Total population size = (total area / area sampled) x number of organisms of that species counted in sample.

Question 9

Why is the total population measured in the random sampling practical an estimate?

Answer 9

The area sampled may not represent the whole area.

Question 10

What factor is normally measured in the transect sampling required practical?

Answer 10

Light intensity

Question 11

Why does the abundance of a plant species increase with distance away from a tree?

Answer 11

Light intensity increases, so more photosynthesis can occur