By Derek Guise
Soil Permeability is dependent upon soil particle size, and the type of material which makes up the soil. Different types of soils across the country, state, and locally affects how much water will make it down into the subsoil and how much will stand on the surface. This lab activity will demonstrate how soil composition affects soil permeability.
To demonstrate the permeability of clay, sand, and organic soil.
- Ring stand
- Circular Clamp
- Clear PVC or other type of tubing at least 20 cm long
- Filter paper or fine screen
- 600 ml beaker
- 250 ml beaker
- Plastic funnel to fit around bottom of PVC tubing
- Stop watch
- Samples of sand, clay and organic potting soil or garden soil
- Place the PVC tubing into the circular ring clamp and connect to the ring stand high enough to allow a 600 ml beaker to be placed beneath the tube.
- Place filter paper or screen into the plastic funnel and attach the wide part of the funnel to the tube with tape. Be sure to tape all the way around the funnel so at to create a watertight barrier.
- Place 100 ml of sand into the tube.
- Add 250 ml of water into the tube. Have a lab partner time how long it takes for water to flow through the sand until all dripping has stopped.
- Repeat steps 3 and 4 with the clay and organic soil.
- Have students create a data table displaying data.
- Have students graph material vs. time in a bar graph.
- Which soil sample demonstrated the most permeability?
- 2 If you were to plant a garden or were a farmer looking for the best type of soil in which to plant a crop, which soil type would you use and why?
- How does soil particle sizes affect the permeability?