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10 Cards in this Set
- Front
- Back
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What percentage of organic matter composition divides O and A horizons?
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12%
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What is the most common element in Earth's crust, and what percent does it compose?
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Oxygen - 47%
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What is the second most common element in Earth's crust, and what percent does it compose?
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Silicon - 28%
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What percent of soil bulk is organic material?
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5%
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What percent of soil bulk is mineral?
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45%
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What percent of soil bulk is pores?
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50%
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What percent of soil bulk is air?
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25%
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What percent of soil bulk is water?
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25%
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What horizon(s) can have granular structure?
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A-horizon
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How does porosity form?
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-eluviation
-burrowing animals -roots, when they die -roots, when they pull out (tree throw) -decaying organic matter |
