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21 Cards in this Set
- Front
- Back
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Parent material |
Underlying bedrock |
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Horizon |
Distinct layers of soil |
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Soil profile |
Nature of horizons |
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Five major horizons |
O, e, a, b and c |
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A horizon |
Contains most of roots, very biologically active, mostly sand, silt and clay |
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O horizon |
Thin layer of decomposing organic matter |
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E |
Below a, lighter in color |
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B horizon |
Zone of accumulation where leeches mixes with parent materials. Bottom of the topsoil |
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C horizon |
Partially weathered parent material |
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Soil texture |
Relative proportions of sand, silt, and clay |
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Loam |
Moxford of three soil types, considered ideal |
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Soil structure |
Shape, size, strength, and arrangement of soil aggregates |
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Macropores, micropores |
Large, hold air, small, holds water |
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Bulk density |
Weight of dried soil per unit of undisturbed soil volume |
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Soil compaction |
Increased bulk density, decreased pore space |
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Buffering capacity |
Resistance in soil to changes of pH |
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Cation |
Positively charged ions |
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Anions |
Negatively charged ions |
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Cation exchange capacity |
Measure of a soils capacity to attract, retain, and exchange positively charged cations |
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Sodic soils |
Sodium occupies an unusually high percent of the CEC |
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Soil food web |
Organisms living in the soil |
