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Parent material is the underlying geological material (generally bedrock or a superficial or drift deposit) in which soil horizons form. Soils typically inherit a great deal of structure and minerals from their parent material, and, as such, are often classified based upon their contents of consolidated or unconsolidated mineral material that has undergone some degree of physical or chemical ...
Soil develops through a series of changes. [2] The starting point is weathering of freshly accumulated parent material.A variety of soil microbes (bacteria, archaea, fungi) feed on simple compounds released by weathering and produce organic acids and specialized proteins which contribute in turn to mineral weathering.
Parent rock. In the earth sciences, parent rock, also sometimes substratum, is the original rock from which younger rock or soil is formed. In soil formation, the parent rock (or parent material) normally has a large influence on the nature of the resulting soil; for example, clay soil is derived from mudstone while sandy soil comes from the ...
As the primary minerals in soil parent material weather, the elements combine into new and colourful compounds. Iron forms secondary minerals of a yellow or red colour, [117] organic matter decomposes into black and brown humic compounds, [118] and manganese [119] and sulfur [120] can form black mineral deposits. These pigments can produce ...
An example of the development of a soil would begin with the weathering of lava flow bedrock, which would produce the purely mineral-based parent material from which the soil texture forms. Soil development would proceed most rapidly from bare rock of recent flows in a warm climate, under heavy and frequent rainfall.
Soil conditions produce uniform or gradual color changes, while reducing environments result in disrupted color flow with complex, mottled patterns and points of color concentration. Sometimes, a distinct change in color within a soil profile indicates a change in the soil parent material or mineral origin. [3]
An example is the German soil systematics. Other systems combine characteristics resulting from soil-forming processes and characteristics inherited from the parent material. Examples are the World Reference Base for Soil Resources [4] (WRB) and the USDA soil taxonomy . [5]
A taxonomy is an arrangement in a systematic manner; the USDA soil taxonomy has six levels of classification. They are, from most general to specific: order, suborder, great group, subgroup, family and series. Soil properties that can be measured quantitatively are used in this classification system – they include: depth, moisture ...