FAO Digital Soil Map of the World (DSMW)

The FAO Digital Soil Map of the World is the digitized version of the FAO-UNESCO Soil Map of the World produced in paper version at scale 1:5 million. It shows 4931 mapping units consisting of soil associations, which are mixtures of different soil types, classified according to the FAO-UNESCO Legend, which defines a total of 106 soil units on the basis of presence of diagnostic properties and 4 non-soil units. The soil associations are characterized in terms of the estimated proportions of the component soil units, the presence of limiting factors or 'phases' (stony, lithic, petric, petrocalcic, petrogypsic, petroferric, phreatic, fragipan, duripan, saline, sodic and cerrado) and the estimated proportions of these soil units in one of 9 texture-slope classes (combinations of coarse-, medium- and fine-textured soils with level to gently undulating, rolling to hilly, and steeply dissected to mountainous topography). For the soil units estimates are provided of physical (% sand, % silt, % clay, bulk density) and chemical properties (pH, organic carbon, CEC, base saturation, C/N ratio, CaCO3-content) in the topsoil and subsoil. DSMW has been superseded by the Harmonized World Soils Database (HWSD), which contains more detailed information on soil distributions for a number of countries, obtained since the publication of all volumes of the Soil Map of the World.