02745nab a2200301 i 4500003000900000005001700009008004100026040001800067072000800085072000800093100002800101100003100129100003400160100003700194100003000231100003700261245006500298500007000363520163500433650002102068650002202089650001402111650002702125773018502152856007902337942000802416999001902424BR-BrBNA20250318162436.0250318b2020    bl.ar|pooa||| 00| 0 eng |  aBR-BrBNAbeng  aP32  aP33  aCipriano-Silva, Rafael   aValladares, Gustavo Souza   aAzevedo, Antônio Carlos de   aAnjos, Lúcia Helena Cunha dos   aPereira, Marcos Gervasio   aPinheiro Junior, Carlos Roberto   aAlluvial soil formation in the plains of northeastern Brazil  aPublicação on-line; 41 ref.; 6 illus; 6 tables; Sumaries (En)  a

ABSTRACT: Soils in alluvial plains of the lower course of the Acaraú River, Ceará State, Brazil, are weakly developed and have a complex distribution in the landscape. This study reports the pedogenic characterization of such soils in an effort to understand their formation. Soil pits were opened in four representative sites, profile morphology was described, and soil samples were collected for chemical, physical, mineralogical, and micromorphological analyses. All profiles had weak pedogenic development, as inferred from their morphological characteristics, lack of B horizon, and high silt/clay ratio. Organic carbon and particle size distributions were heterogeneous in Fluvisol, Planosol, and Solonchak, in agreement with their sedimentary nature. Intrinsic characteristics of each profile indicated variations in pedogenic processes related to depositional conditions, which, in turn, were determined by the alluvial nature of sediments and water table dynamics. Consequently, Fluvisols at higher elevations showed reduced pedogenic development. In adjacent areas, Planosols showed pores filled with clay minerals and a texture gradient, indicative of past lessivage. Vertisol was identified in small depressions and exhibited intense pedoturbation and high sodium concentration in deep layers. Solonchak had a high degree of hydromorphism, high sodium concentration, and high electrical conductivity. The distinct pedogenesis of alluvial plain soils in Northeastern Brazil is evidenced by their morphological, chemical, and physical properties.

Keywords: clay eluviation, pedogenesis, Inceptisol, pedoturbation.  aGENÊSE DO SOLO  aANÁLISE DO SOLO  aPEDOLOGIA  aCONDIÇÃO AMBIENTAL0 08089345421dViçosa-MG Sociedade Brasileira de Ciência do Solo 1977o2024-5955tRevista Brasileira de Ciência do Solo (Brazil)x0100-0683gv. 44 p. 1-18; (2020)wBR2024004912  uhttps://www.scielo.br/j/rbcs/a/3g7LQvRQ5kQPwrJL8sLvLgN/?format=pdf&lang=en  cANA  c330498d330498