| A | B |
|---|
| Mechanical or chemical surface processes that break rock into smaller and smaller pieces | Weathering |
| Physical processes that break rock apart without changing its chemical makeup; can be caused by ice wedging, animals, and plant roots. | Mechanical weathering |
| Mechanical weathering process that occurs when water freezes in the cracks of rocks and expands, causes the rock to break apart. | Ice wedging |
| Occurs when chemical reactions dissolve the minerals in rocks or change them into different minerals. | Chemical weathering |
| Occurs when some materials are exposed to oxygen in the air. | Oxidation |
| Average weathering pattern in an area over a long period of time; can be classified by temperature, humidity, precipitation, and vegetation. | Climate |
| A mixture of weathered rock and mineral fragments, decayed organic material , mineral fragments, water and air that can take thousands of years to develop | Soil |
| Dark-colored, decayed organic matter that supplies nutrients to plants and is found mainly in topsoil p. 190 | Humus |
| Each layer in soil profile-horizon A (top layer of soil), horizon B (middle layer), and horizon C (bottom layer). | Horizon |
| Vertical section of soil layers, each of which is a horizon p. 190 | Soil profile |
| Twigs, leaves, and other organic matter that help prevent erosion and hold water and may eventually be changed into humus by decomposing organisms. | Litter |
| Removal of minerals that have been dissolved in water. | Leaching |
| Method of reducing soil erosion; plant stalks are left in the field after harvesting and the next year's crop is planted within the stalks without plowing. | No Till Farming |
| Planting along the natural contours of equal elevation. | Contour farming |
| A farming method used to reduce erosion on steep slopes p. 199 | Terracing |
