With the development of soil classification to the fourth category level of the Brazilian Soil Classification System – SiBCS, it seeks the development and standardization of proposals for the classification of soils in 5 th and 6 th categorical levels (family and series). In this sense, this paper aims to available the viability of the humic fractions for the classification of diagnostic horizons in the 5th or 6th categorical levels (family and series) of SiBCS. For the development of the […]