Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

Which type of soil is smooth and tends to hold water effectively?

1. Loamy soils

2. Sandy soils

3. Clay soils

4. Gravel soils

The correct answer is: Clay soils

Clay soils are characterized by their small particle size and smooth texture. These fine particles allow clay to hold water effectively, making it capable of retaining moisture for plants and other organisms that rely on water availability in the soil. The compact nature of clay contributes to its ability to hold water better than coarser soils, such as sandy or gravel soils, which have larger particles and generally drain water more quickly. Clay soils also benefit from their ability to bind together, creating a dense structure that reduces porosity and limits water movement. As a result, they can become waterlogged in wet conditions but are also beneficial in retaining moisture during dry periods. This property makes them particularly useful for certain types of agriculture and gardening where water retention is essential.