FORESTRY
ECOLOGY AND ENVIRONMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Clay
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Gravel
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Silt
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Sand
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Detailed explanation-1: -Clay is the most porous sediment but is the least permeable. Clay usually acts as an aquitard, impeding the flow of water. Gravel and sand are both porous and permeable, making them good aquifer materials. Gravel has the highest permeability.
Detailed explanation-2: -Because its grains are very small, there are a lot of (small) pore spaces in between them. What clay does not have is good permeability, which is a measure of how “connected” these pore spaces are. Clay can hold a lot of water, but it doesn’t let it flow very well.
Detailed explanation-3: -Coarse-textured sandy and gravelly soils have the largest pores and the most rapid permeabilities. Fine-textured clayey soils have very tiny pores and very slow permeability rates. Medium-textured loams, silt loams, and clay loams have intermediate rates of soil permeability.