160 likes | 541 Views
Grade 7 Science . Earth and Space Science: Earth’s Crust and resources (EC). Lesson 8 a . What is soil?. Soil is not one thing but rather a blend of many constantly changing components Did you know that three to six different types of soil may be found in your backyard?. Soil.
E N D
Grade 7 Science Earth and Space Science: Earth’s Crust and resources (EC)
What is soil? • Soil is not one thing but rather a blend of many constantly changing components • Did you know that three to six different types of soil may be found in your backyard?
Soil • What is in soil? • Sand – composed of silicates and is porous -Nutrients leech out easily -little ability to hold moisture • What does porous mean? • Why is this important? • It allows air and water to penetrate through the soil to reach plant roots
Silt – made up of smaller particles - helps hold moisture and nutrients • Clay – made up of finely ground materials that cling together - rich in nutrients -Why can too much clay in soil cause problems? • Too much clay in soil will cause it to become impenetrable to moisture and air