1. Choose one soil sample, A, B or C. 2. Place 10 cm of the soil into a clear jar and fill to the top with water. 3. Shake the jar well and leave to settle for twenty-four hours. 4. After this period, the soil will have settled into the heaviest material at the bottom and lighter material on top.
5. The lightest material (humus) will be on top.
6. Measure this material to discover humus content.
7. Record your measurements and draw a diagram/take a photograph of your soil jar. (Refer to the results table, p. 238.)
Shaken & settled Soil sample
Humus Clay Silt
Sand Cloudy water in the top of the jar indicates plenty of clay
Task 4: Measure the moisture and air content of one soil sample You will need
Oven tray Weighing scales Instructions
1. Choose one soil sample, A, B or C. 2. Weigh your soil sample and record the result. (Refer to the results table, p. 238.) 3. Place soil sample on a tray and put it into an oven on a high heat for ten minutes. (If you don’t have an oven, place the sample near a radiator for a few hours to give it time to dry out.)
4. Remove sample from oven and weight it again.
5. Record the new weight. 6. Subtract the ‘after heating’ measurement from the ‘before heating’ measurement. The difference between the weights is as a result of the removal of moisture/air due to heating.
7. You could take photographs of the soil sample before and after heating. 235
