Theory question 206
Soils(a) Explain any four processes of soil formation (b) In what four ways is soil important?
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(a) Weathering of parent rock into small mineral particles; addition of organic matter (humus) from dead plants and animals; leaching/eluviation (washing down of minerals) and illuviation (deposition lower down) forming horizons; laterisation in hot wet areas; podzolisation in cool wet areas; calcification in dry areas; action of living organisms (earthworms, bacteria) mixing the soil.
(b) Medium for plant growth and food production; supplies nutrients and water to plants; habitat for organisms; building materials (clay, laterite); foundation for buildings and roads; raw materials for pottery and bricks; stores and filters water.
Name the process and say what it does to the soil.