Question

Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well establishedas early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria taken an active part in the process

Answer 1

In agriculture, leaching is the loss of water-soluble plant nutrients from the soil, due to rain and irrigation. Soil structure, crop planting, type and application rates of fertilizers, and other factors are taken into account to avoid excessive nutrient loss. Leaching may also refer to the practice of applying a small amount of excess irrigation where the water has a high salt content to avoid salts from building up in the soil (salinity control). Where this is practiced, drainage must also usually be employed, to carry away the excess water...

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