The Food and Agriculture Organization of the United Nations (FAO) and the International Institute for Applied Systems Analysis (IIASA) combined the available regional and national soil information with the information already contained within the 1:5,000,000 scale FAO-UNESCO map, into a new comprehensive Harmonized World Soil Database (HWSD_v121) at a resolution of about 1 km (30 arc seconds) consisting of a 30 cm topsoil layer, and a 70 cm subsoil layer.
Associated files include: “Lookup_Soil_HWSD(v121).txt”, and “SWAT2012.mdb”.

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Purchase the map, SWAT lookup table, and SWAT2012.mdb
Global Soil HWSD