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