Phaeozem

A phaeozem in the FAO World Reference Base for Soil Resources is a dark soil with a high base status, but without a calcareous soil horizon within one metre of the soil surface. Phaeozems correlate with the udolls and aquolls (mollisols) of the USDA soil taxonomy.

These soils are found mainly in humid and sub-humid tall-grass steppes; there are extensive areas of them in the United States, Argentina and China. Phaeozems form from unconsolidated sediments such as loess and glacial till and typically have organic matter contents of about 5% and a pH of 5 - 7.

Intensive agricultural use is widespread and includes wheat, soybean and cotton production and improved pastures for cattle.

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