6 Do you think this method introduces a source of error? If so, how might the error be reduced?
The following data was collected by one group of students:
Quadrat number Number of rushes 1
2 3 4 5 6 7 8 9
10
2 4 3 0 0 2 1 3 2 1
7 Calculate the mean number of rushes per quadrat. Calculate the range of rushes per quadrat.
8 Using your answer to question 3, calculate an estimate of the total number (abundance) of rushes in the habitat.
Over the next week, the students analysed the percentage moisture content of each of their fresh soil samples. The raw data is recorded in the table below.
Quadrat number 1
2 3 4 5 6 7 8 9
10
Mass of fresh soil (g) 2.04
2.03 2.09 1.97 2.01 2.14 1.87 2.05 2.05 2.03
Mass of oven-dried soil (g) 1.29
1.10 1.30 1.48 1.47 1.48 1.33 1.19 1.37 1.44
9 Using this data, calculate the percentage soil moisture for each quadrat using the following formula:
Percentage soil moisture = ( [Mass of fresh soil – mass of oven-dried soil] [Mass of fresh soil]
10 With the aid of a labelled diagram, describe the steps taken in the measurement and calculation of soil moisture content.
11 Produce a scatter plot of soil moisture content (x-axis) versus number of rushes (y-axis). Do you see any trend in the data? If yes, explain why you think this is the case.
12 Could the results of this survey be used to assess the effects, if any, of a drainage scheme within the park? Would a similar follow-up study be necessary?
