Boundary between Soil and Saprolite in Alisols in the South of Brazil

Revista Brasileira de Ciência do Solo

Fabrício De Araújo Pedron¹  Rodrigo Bomicieli De Oliveira¹  Ricardo Simão Diniz Dalmolin¹  Antonio Carlos De Azevedo¹  Ricardo Vargas Kilca¹ 

关键词: pedology;    soil classification;    soil morphology;    pedometrics;    pedologia;    classificação de solos;    morfologia do solo;    pedometria;   

DOI  :  10.1590/01000683rbcs20140229

来源: SciELO

【 摘 要 】

Despite numerous studies conducted on the lower limit of soil and its contact with saprolite layers, a great deal of work is left to standardize identification and annotation of these variables in the field. In shallow soils, the appropriately noting these limits or contacts is essential for determining their behavior and potential use. The aims of this study were to identify and define the field contact and/or transition zone between soil and saprolite in profiles of an Alisol derived from fine sandstone and siltstone/claystone in subtropical southern Brazil and to subsequently validate the field observations through a multivariate analysis of laboratory analytical data. In the six Alisol profiles evaluated, the sequence of horizons found was A, Bt, C, and Cr, where C was considered part of the soil due to its pedogenetic structure, and Cr was considered saprolite due to its rock structure. The morphological properties that were determined in the field and that were different between the B and C horizons and the Cr layer were color, structure, texture, and fragments of saprolite. According to the test of means, the properties that support the inclusion of the C horizon as part of the soil are sand, clay, water-dispersible clay, silt/clay ratio, macroporosity, total porosity, resistance to penetration, cation exchange capacity, Fe extracted by DCB, Al, H+Al, and cation exchange capacity of clay. The properties that support the C horizon as a transition zone are silt, Ca, total organic C, and Fe extracted by ammonium oxalate. Discriminant analysis indicated differences among the three horizons evaluated.

【 授权许可】

CC BY   
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