1. How important are air spaces between soil particles?
2. Why does vegetation vary with soil variation?
3. Which soil allows water to drain more efficiently?
| Purpose: | 1. To identify components of soil and how
those components determine soil function.
2. To explain how different soil types determine ecosystem characteristics. 3. To predict how soil affects water filtration (percolation). |
| Materials: | small garden trowel, hand lens, small plastic sandwich bags, beakers with stirring rods or clear plastic jars with lids, pan balance scales, water, 100ml graduated cylinder, graph paper, small metric ruler |
| Procedure: | 1. Determine 5 soil collection sites where
you may obtain characteristically different soil samples. Place them in
the plastic bags and label as to site.
2. Examine soil samples. For each sample, create a report that answers the following fundamental questions. a) Where is the soil site?3. Measure 100ml of dry soil from each sample into each beaker or jar using the graduated cylinder. 4 . Record weight of soil and beaker in a table similar to the one below. 5. Slowly pour water into the beaker until it reaches the top edge of the soil. 6. Weigh each container again and fill the remaining spaces in
the table.
7. Continue to add water until the level is 5cm above the soil. 8. Shake or stir the sample vigorously. 9. Allow samples to settle completely (app. 2hr.) 10. Record observations about layers. |
|
Think about this:
1. How important are air spaces between soil particles? 2. Why does vegetation vary with soil variation? 3. Which soil allows water to drain more efficiently? |
Extension:
1. Graph soil profile results by comparing layers in each sample. (Ratios of sand to silt or clay in each sample.)
2. Obtain a copy of your county’s soil survey or a map of aerial photographs
marked for different types of soil. Compare types of soil with what is
evident in each area. Are there roads, highways, farmland, ponds, etc.?