Soil Properties—We Dig Dirt!
This week it may have looked like we had a great time playing with dirt, but we were actually studying soil! Our young soil scientists learned about geological, biological, and topographical factors that contribute to soil formation over hundreds and thousands of years. Ask your student about the role that microorganisms play in soil formation or to explain how soil can be a solid, a gas, and a liquid.
In our activity, students examined different soils. They noticed that soil colors relate to what is in the soil, for instance, dark brown and black soils tend to contain lots of broken down organic material. Students also observed the texture of the soils, noting that some soils contain smaller particles than others. Finally, students measured field capacity, which tells us how well soils can hold water. All of these factors (color, texture, and water retaining ability) are important in determining how good a soil might be for growing plants. Have your student help you look more closely at the soil in your own yard or park!
We need to protect our soil because it is important to every living organism on earth. Healthy soil allows plants to grow, and plants are essential to life along our entire food chain. Soil also helps filter out impurities (e.g., acid rain, industrial wastes) before they can reach our water supplies. The student follow-up activity illustrates the filtering abilities of soil using dark colored grape Kool-Aid. Give it a try with your student and prepare to appreciate our soils even more. The students seemed to really enjoy the lesson and were eager to get their hands in the dirt so to speak. They were also very interactive even though this lesson has a lot of teaching time along with the hands on activities.