Soils under restinga vegetation on the Cardoso Island (SP). II – Mineralogy of silt and clay fractions
01/Dec/2007
Restinga is a typical vegetation on quartzitic, sandy, nutrient-poor parent materials along the Brazilian coast.. Podzolization is the main pedogenic process in restinga soils and Spodosols and Quartzipsamments with incipient podzolization are the most common soils. Podzolization is frequently studied in cold climate regions, while mineralogical studies of Spodosols in tropical climate on quartzitic parent material are scant. In this work, soils under restinga vegetation on the Ilha do Cardoso-SP, Brazil were studied to identify the mineralogical assembly of silt […]
Pedogenesis in an oxisol-spodosol sequence at the upper rio Negro region, Amazonia
01/Jun/2002
This paper deals with the genesis of hydromorphic sandy soils with spodosol morphology found in extensive flat surfaces, in which isolated zones with undulating relief emerge, containing well drained oxisols. The objective of this study was to explain the existence of pedogenetic relationship in an oxisol-spodosol system, and to verify the possible development of the sandy materials as a consequence of oxisol transformation. For this purpose, we characterized the morphology of the soils and their physical, chemical and mineralogical attributes. […]
Fragipans and duripans of the low coastal plateau depression in Northeastern Brazil: an evolution proposal
01/Dec/2001
Fragipans and Duripans are frequently found in soils developed from sediments of the Barreiras Formation, in the low coastal plateaus of northeastern Brazil. Previous studies in arid regions have attributed Duripan cohesion to the amorphous silica. However, the Duripans and Fragipans in northeastern Brazil are located in semi-arid and high annual precipitation level zones (1.500 to 2.000 mm year-1). This study, based on a detailed characterization of soils from four depressions with different sizes, aimed to propose an evolution scheme […]