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 | Definition 
 
        | the process that breaks down rocks and other substances at earth's surface |  | 
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        | the movement of rock particles by wind,water,ice,or gavity |  | 
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 | Definition 
 
        | the type of weathering in which is physically broken into smaller pieces |  | 
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 | Definition 
 
        | the grinding away of rock particles carried by water,ice,wind,or gravity |  | 
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 | Definition 
 
        | wedges of ice in rocks widen and deepen cracks |  | 
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 | Definition 
 
        | the process that breaks down rock through chemical changes |  | 
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 | Definition 
 
        | means that a material is full of tiny,connected air spaces that allow water to seep through it |  | 
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 | Definition 
 
        | the loose,weathered material on Earth's surface in which plants can grow |  | 
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        | the solid layer of rock beneath the soil |  | 
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        | Dark-colored organic material in the soil |  | 
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 | Definition 
 
        | Rich fertile soil that is made up of about parts clay, sand, and silt |  | 
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 | Definition 
 
        | layer of soil that differs in color and texture from the layers above or below it. |  | 
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 | Definition 
 
        | a crumbly dark brown soil that is a mixture of humus, clay, and other minerals |  | 
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 | Definition 
 
        | usualy consists of clay and other particles washed down from A horizon, but little humus |  | 
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 | Definition 
 
        | the organisms that break the remains of dead organisms into smaller pieces and digest them with chemicals |  | 
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 | Definition 
 
        | a loose layer plants form when they shed leaves |  | 
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 | Definition 
 
        | thick mass of tough roots at the surface of the soil |  | 
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 | Definition 
 
        | one that is naturally replaced in in a relatively short time |  | 
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        | an area where wind erosion caused severe loss of topsoil during the 1930s |  | 
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 | Definition 
 
        | the practice of plowing fields along the curves of a slope |  | 
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 | Definition 
 
        | the management of soil to prevent its destruction |  | 
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        | Term 
 | Definition 
 
        | disturbs the soil and its plant covers as little as possible |  | 
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