000			03183nab a2200265 i 4500
003			BR-BrBNA
005			20250318164348.0
008			250318b2020 bl.ar|pooa||| 00| 0 eng |
040			_aBR-BrBNA _beng
072			_aP32
072			_aP33
100			_aHeberle, Daniel Alexandre
100			_aAlmeida, Jaime Antonio de
100			_aTorrado, Pablo Vidal
245			_aCalcination as an alternative method to classify Spodosols on the second categorical level
500			_aPublicação on-line; 24 ref.; 3 illus; 3 tables; Sumaries (En)
520			_a ABSTRACT: The classification of Spodosols on the second categorical level (suborder), according to the Brazilian Soil Classification System (SiBCS), is done by observing the colors of genetic horizons in the field. The presence or absence of iron oxides is the main factor for this classification, and the color of the horizon is the criterion currently adopted. However, the simple observation of color in the field can be mistaken and cause an error in the definition of the second categorical level. This occurs when spodic horizons that do not contain iron oxides show high chroma color, or dark color due to the organic matter content, which masks the presence of iluviated Fe produced by podzolization. This can lead to errors, such as classifying Humiluvico horizons as Ferriluvico, and Ferri-humiluvico horizons as Humiluvico. These misunderstandings are currently solved through complex analyses using specific extractors and sophisticated equipment. Thus, obtaining a simple, fast, and inexpensive method to confirm the presence or absence of iron oxides in samples of spodic horizons is needed. This study tested an alternative method to assist in the determination of the second categorical level of the class of coastal plain Spodosols. The method consists of calcining samples in a muffle at 600 °C for 6 h. The calcination enabled to identify spodic horizons with and without presence of iron quickly; the result was compared with selective extraction analyses carried out using three different extractors: sodium pyrophosphate, ammonium acid oxalate, and sodium dithionite-citrate. The results obtained from these methods (calcination in muffle and selective extraction of iron oxides) enabled the identification of samples presenting colors varying from yellow to reddish, indicating the presence of iron, whereas those with the whitish color indicated absence or very low iron oxide levels. The 12 profiles of Spodosols were described and classified according to the SiBCS, and six profiles needed to be reclassified after the calcination procedure, which proved to be efficient. Keywords: Podzol, spodic B horizon, soil classification, Podzolization.
650			_aCLASSIFICAÇÃO DO SOLO
650			_aANÁLISE DO SOLO
650			_aSANTA CATARINA
773	0		_0808 _9345421 _dViçosa-MG Sociedade Brasileira de Ciência do Solo 1977 _o2024-5955 _tRevista Brasileira de Ciência do Solo (Brazil) _x0100-0683 _gv. 44 p. 1-15; (2020) _wBR2024004917
856			_uhttps://www.scielo.br/j/rbcs/a/QSjLBKJq4ftTtGpNZTtGBBw/?format=pdf&lang=en
942			_cANA
999			_c330500 _d330500