| A | B |
|---|
| weathering | the process by which rock materials are broken down by physical and chemical processes |
| mechanical weathering | the breakdown of rock by physical means such as abrasion, wind, water, and gravity |
| frost action | the alternate freezing and thawing of soil and rock |
| ice wedging | a type of frost action where water seeps into rocks, freezes, then expands |
| abrasion | the grinding and wearing away of rock surfaces through mechanical weathering |
| chemical weathering | the process by whick rocks break down as a result of a chemical process like exposure to water, acids, or air |
| acid precipitation | rain, sleet or snow that contains a high concerntration of acids |
| karst feature | a limestone cavern |
| oxidation | the chemical reaction in which an element is exposed to moisture and air |
| differential weathering | softer, less weather resistant rock is worn away, and leaves harder rock behind |
| soil | loose mixture of small mineral fragments, organic material, water, and air that can support the growth of vegetation |
| parent rock | rock that is the source of soil |
| bedrock | layer of rock beneath the soil |
| residual soil | soil that remains above its parent rock |
| transported soil | soil that is blown or washed away from parent rock |
| soil texture | the soil quality that is based on porportions:% of soil types that make up the soil |
| soil structure | the arrangement of the particles that make up the soil |
| infiltration | the ability of water to flow through a soil |
| humus | dark, organic material in soil |
| soil horizons | layers of soil that are formed |
| leaching | the removal and transport of substances that can be dissolved by the passing of water |
| soil conservation | a method to maintain the fertility of soil: keeps soil safe from erosion and nutrient loss |
| erosion | the process by which wind, water, ice, and gravity move soil and sediment from one place to another |
| land degredation | when soil becomes infertile from overuse |
| desertification | when a fertile area becomes a desert |
| contour plowing | when a farmer plows rows across the slope of the hills |
| terracing | plowing land so that one steep hill becomes a series of smaller hills |
| no-till farming | leaving old stalks in the fields |
| cover crops | crops that are planted between harvests to replace nutrients and prevent erosion |
| crop rotation | planting diffent crops in the same field from year to year. |
