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4 Cards in this Set
- Front
- Back
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what is the TOPSOIL broadly composed of? What is the significance of topsoil?
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The mineral particles of weathered rocks mixed with the HUMUS (the remains of dead organisms and other organic mattter.
The toppsoild is the the most important soil layer for the growth of plants. |
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what are LOAMS, and what are they composed of?
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Loams are the most feritle topsoils, which are composed of roughly equal amounts of sand, silt and clay. Loamy soilds have enough small particles to provide large surface area for the adhesion and retention of mineral and water. the sand particles enable efficient diffusion of oxygen to the roots.
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Describe how the soil retains inorganic components in the topsoil.
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Inorganic components: most soil particles are negatively charged, so catoins adhere to the soil particles (therefore are not easily lost by leaching). The anions do not bind to soil and therefore are lost easily by leaching.
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How do roots absorb cations?
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By cation exchange (form carbonic acid, the H+ replaces the cations. )
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