01800naa a2200217 a 450000100080000000500110000800800410001910000250006024501090008526000090019452011800020365000120138365000230139565000140141865000090143265300270144170000190146870000170148770000200150477300580152419734102015-02-18       2013    bl uuuu     u00u1 u    #d1 aMAIA, C. M. B. de F.  aSoil organic matterbchemical and physicl characteristics and analytical methods.h[electronic resource]  c2013  aSoil organic matter (SOM) holds a prominent place among the many indicators that are studied in relation to soil function. Different viewpoints are reflected in characterizing SOM, depending on the study procedures used, or the focus of the researchers. There are many possibilities for the isolation and fractionation of SOM and this has led to a plurality of interpretations and conclusions. Transformations to organic materials that lead to the more recalcitrant components of SOM are outlined, and the associations which these materials can have in the soil environment, and aspects of their compositions are referred to. A review is given of the organic matter pools in soils, of their functions, and of the controls which they have in soil systems. A succinct review is given of physical fractionation procedures for SOM. This approach is highly relevant, though rarely used in modern studies of SOM. The merits and demerits of wet oxidation procedures, relative to dry combustion for determining soil organic carbon contents are discussed, and reference is made to the emerging chemometric techniques based on the use of Near (NIR) and Mid (MIR) infrared spectroscopy.  aCarbono  aMatéria Orgânica  aMedição  aSolo  aIndicador de qualidade1 aNOVOTNY, E. H.1 aRITTL, T. F.1 aHAYES, M. H. B.  tCurrent Organic Chemistrygv. 17, p. 2985-2990, 2013.