Reference Base for Soil Resources (WRB), Mollisols are split up into Chernozems, Kastanozems and Phaeozems. Shallow or gravelly Mollisols may belong to the Leptosols. Many Aquolls are Gleysols, Stagnosols or Planosols. Mollisols with a natric horizon belong to the Solonetz. See also Pedogenesis Pedology (soil study) Soil classification Soil science Soil type References Brady, N.C. and Weil, R.R. (1996). ‘The Nature and Properties of Soils.’ 11th edition. (Prentice Hall, New Jersey). Buol, S.W., Southard, R.J., Graham, R.C., and McDaniel, P.A. (2003). ‘Soil Genesis and Classification.’ 5th edition. (Iowa State University Press - Blackwell, Ames.) External links Pedology Types of soil