| A | B |
|---|
| Soil | the loose material that covers much of Earth's land surface |
| natural resource | any useful material from Earth, such as tress, petroleum, air, and water |
| conservation | the wise use of natural resources |
| topsoil | mixture of weathered rock and humus (Top layer) |
| Humus | decayed plant and animal matter |
| Subsoil | reddish or yellowish layer made of clay particles that have been weathered (2nd layer-right under topsoil |
| weathered rock | rock that lies under the looser soil above it(or right above the bottom layer) |
| Bedrock | Hard lower surface of soil (Bottom layer) |
