The following colleagues collaborated in the preparation of this document (in order of importance): Dr. Pablo Miguel (UFPel), Jean Michel Moura Bueno (UFSM), Dr. Ricardo Simão Diniz Dalmolin (UFSM), Andrisa Balbinot (UFSM), Dr. Lúcia Helena Cunha dos Anjos (UFRRJ), Dr. Gustavo de Mattos Vasques (Embrapa Soils), and Dr. Gerard B. M. Heuvelink (ISRIC - World Soil Information). The CAPES Foundation, Ministry of Education of Brazil, and the CNPq foundation, Ministry of Science and Technology of Brazil, supported the production of this document.