Definition
Soils with a thick, dark brown topsoil, rich in organic matter and a calcareous or gypsum-rich subsoil.

Distribution
Kastanozems occur on the southern steppes of Ukraine, southern Russia, Mongolia and the Great Plains of the USA. There are 465 million hectares of these soils wordwide. Kastanozems are associated with Chernozems, Calcisols, Gypsisols, Solonetz and Solonchaks.