Rough Draft Experimental Design Diagram
Location: My Backyard
When you take the mass before and after you have to find the change in percentage so you can find the percentage of moisture that was in the soil sample after each visit. If you take the difference in the two masses it will be different based on how much dirt you used. Use at least 30g of the material you are drying out.
http://www.currentresults.com/Weather/US/average-state-precipitation-in-fall.php
Average rainfall in the months of September-November decreases steadily. If you look at the average rainfall in Michigan for the summer and winter months it steadily decreases as time passes. Spring time is the only time when the precipitation increases.
Hypothesis: If the amount of time increases, then the amount of soil moisture will decrease because it doesn’t rain as much in the fall and there isn’t much precipitation until snow falls.
5 controlled variables
-same location of rain gauge
-amount of time spent in the incubator
-depth of the sample dirt
-location of sample dirt
-same container for the dirt in the incubator
Materials
-ziploc bags, small garden shovel, bucket for rain gauge, incubator
Procedure:
1. Gather a bucket for a rain guage on the first visit only, a small gardening shovel, and a small ziploc bag.
2. Go to the selected spot in the plot of land
3. Use the small shovel to dig a small hole about 3 inches deep.
4. Take a shovelful of soil and place into the ziploc baggie.
5. Put your name on the bag and your visit number so you won’t lose it in the incubator.
6. Take the bag to school
7. Put a crucible on the scale and tear it so it will subtract the weight of the crucible.
8. Place your dirt sample in 3 crucible and take the masses.
9. Place your crucibles into the incubator for between 24-48 hours depending on the moisture in the soil.
10. Take the soil sample out of the incubator when finished.
11. Take the mass of the soil sample once again.
12. Take the percentage of change between the two masses not the difference between the two.
13. Write down the percentage change on a chart
14. Repeat steps 1-13 for each of the 6 visits.
Data Tables
Percent Change in Mass
depends on the Date
|
|
|
|
Visit No#
|
Before Masses (grams)
|
After Masses (grams)
|
Percent Changed (percent)
|
#1 Sept 9
|
27.73, 28.28, 28.30
|
26.01, 26.59, 26.62
|
0.062, 0.059, 0.058
|
#2 Sept 25
|
27.81, 31.08, 28.23
|
26.52, 29.48, 26.88
|
0.046, 0.051, 0.048
|
#3 Oct. 14
|
28.78, 28.76, 26.55
|
26.68, 26.53, 24.75
|
0.073, 0.051, 0.048
|
#4 Oct. 30
|
26.78, 26.69, 28.02
|
24.66, 24.79, 25.67
|
0.079, 0.071, 0.084
|
#5 Nov. 13
|
25.59, 30.65, 29.70
|
23.54, 28.44, 27.44
|
0.081, 0.072, 0.076
|
#6 Nov. 22
|
27.78, 28.65, 28.52
|
25.61, 26.50, 26.24
|
0.078, 0.075, 0.080
|
Source:
|
Daniel Walters
|
November 2013
|
|
Precipitation depends on the Dates
|
|
Dates
|
Precipitation (in.)
|
Sept. 2-8
|
0.00
|
Sept. 9-15
|
0.61
|
Sept. 16-22
|
0.90
|
Sept. 23-29
|
0.45
|
Sept. 30-Oct. 6
|
1.45
|
Oct. 7-13
|
0.27
|
Oct. 14-20
|
3.03
|
Oct. 21-27
|
2.88
|
Oct. 28-Nov. 3
|
2.24
|
Nov. 4-10
|
3.25
|
Nov. 11-17
|
1.74
|
Nov. 18-24
|
1.57
|
Nov. 25-Dec. 1
|
0.00
|
Source:
|
Daniel Walters November 2013
|
