134 results

Soils under restinga vegetation on the Cardoso Island (SP). II – Mineralogy of silt and clay fractions

Felipe Haenel Gomes, Pablo Vidal-Torrado, Felipe Macías, Valdomiro Severino de Souza Júnior, Xosé Luis Otero Perez

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 […]

Geochemical and mineralogical evolution in alteration profiles on serpentinized rocks in southwestern Minas Gerais, Brazil

Pablo Vidal-Torrado, Rosa Calvo, Felipe Macias, Sebastião G. Carvalho, Alexandre Christofaro Silva

01/Oct/2007

The geochemical and mineralogical evolution was studied in three different alteration profiles of ultramafic (serpentine) rocks near Alpinópolis and Fortaleza de Minas, in southwestern Minas Gerais State (Brazil). Soil moisture and temperature regimes are udic and thermic, respectively. The current chemical and mineralogical evolution degree is moderate compared to other basic and ultramafic material of the same area and is characterized by significant losses of Na and Mg and, to a lesser extent, of Ca and Si. Very little K […]

Relationship between soil organic matter and slope steepness in a toposequence of Oxisol in southern Minas Gerais, Brazil

Alexandre Christofaro Silva, Pablo Vidal Torrado, Martha González Pérez, Ladislau Martin Neto, Felipe Macias Vasquez

01/Oct/2007

The accumulation and stability of soil organic matter are related to slope steepness. The relationships between steepness and the humification degree of humic acids, the charcoal fragment content and its radiocarbon age were quantitatively evaluated. Four Latosols (Oxisols) of the summit, shoulder, back slope and back/foot slope of a toposequence under pasture in a cratonic area in the southern Minas Gerais state, southwest Brazil, were used. The parent material of the Latosols was gneiss of the Precambrian complex, with an […]

Characterization and classification of cambisols from the archipelago Fernando de Noronha, Pernambuco, Brazil

Flávio Adriano Marques, Mateus Rosas Ribeiro, Sheila Maria Bretas Bittar, José de Almeida Lima Neto, José Fernando Wanderley Fernandes Lima

01/Oct/2007

The objective of this work was to characterize and classify Cambisols of the Fernando de Noronha Archipelago to test and improve the Brazilian System of Soil Classificaton (SiBCS). For this ecological complex of touristic importance, information on soil characteristics and landscape distribution is essential to plan the land use and government actions focusing on sustainable land use. Based on a Detailed Soil Survey of the Fernando de Noronha Archipelago, six representative Cambisol profiles were morphologically characterized and samples were collected […]

Characterization and classification of plintosols from Pinheiro, Maranhão state, Brazil

Lúcia Helena Cunha dos Anjos, Marcos Gervasio Pereira, Daniel Vidal Pérez, Doracy Pessoa Ramos

01/Oct/2007

The objective of the study was to characterize and classify four Plintosols (Ultisols and Entisols with plinthite) in Pinheiro county, Maranhão state (Brazil), to validate the new classes proposed in the Brazilian System of Soil Classification (SiBCS). Four pedons were selected in different hill slope positions: shoulder, backslope, footslope, and toeslope. The parent material consisted of ferruginous sandstone of the Itapecuru Formation and colluvial and alluvial sediments. Soil profiles were morphologically described and each horizon analyzed for physical, chemical and […]

Relationships between local farmers’ and pedologists’ knowledge on soil science: A case study in Rio Pardo de Minas, Brazil

João Roberto Correia, Lúcia Helena Cunha dos Anjos, Antonio Carlos Souza Lima, Delma Pessanha Neves, Luciano de Oliveira Toledo, Braz Calderano Filho, [...]

01/Oct/2007

One of the challenges of constructing agricultural systems that aim to be sustainable, is the usage of scientific knowledge adapted to the peculiar social situation. For this purpose it is necessary to consider the knowledge that farmers accumulated over time and space. In the case of the soil resources, a modest amount of the local knowledge is considered in classrooms and in soil research. This is a constraint to the application of technologies based on local scientific knowledge involving traditional […]

Quaternary evolution, particle distribution in soils and sedimentary environment in mangroves in São Paulo State, Brazil

Valdomiro Severino de Souza-Júnior, Pablo Vidal-Torrado, Moysés Gonzalez Tessler, Luiz Carlos Ruiz Pessenda, Tiago Osório Ferreira, Xose Luiz Otero, [...]

01/Aug/2007

Particle distribution in soil or sediments of coastal plains contributes to the understanding of the sedimentation processes in estuaries. It is an important attribute for applications in studies of palaeoenvironmental reconstruction, geochemical cycles and environmental pollution such as heavy metal and oil spill contamination, which are relatively common in these sites due to human impact. With the objective of characterizing the sedimentary environments according to the particle size and the process of quaternary evolution, 14 mangroves along the São Paulo […]

Soil-landscape relationships in a sandstone-basalt lithosequence in Pereira Barreto, São Paulo

Milton César Costa Campos, José Marques Júnior, Gener Tadeu Pereira, Rafael Montanari, Livia Arantes Camargo

01/Jun/2007

The focus of our study were to study soil-landscape relationships in a sandstone-basalt transition lithosequence and to compare the limits of geomorphic surfaces mapped in the field with those mapped by geostatistical techniques. An area of 530 ha was mapped using GPS equipment in order to generate a model of digital elevation, which allowed for the establishment of a transection of 2.100 m from the hill top downwards. Along the transection, the altitude was measured at 50 m regular intervals […]

Spatial variability of soil physical attributes used for soil mapping in small headwater catchments of the southern Amazon

João Paulo Novaes Filho, Eduardo Guimarães Couto, Virlei Alvaro de Oliveira, Mark S. Johnson, Johannes Lehmann, Susan S. Riha

01/Feb/2007

The northwestern region of Mato Grosso State consists of complex landscapes due to ongoing geomorphologic activity that contributes to the occurrence of different soil classes over small distances, which complicates soil sampling strategies. This study was conducted in Juruena (MT), with the objective of identifying pedologic classes in undisturbed forested headwater catchments by examining the spatial variability of soil texture and color, and taking elevation and topographic position into consideration. The spatial variability of soil texture and color were determined […]

Genesis of hardened horizons, fragipan and duripan in soils of the coastal tablelands of south Bahia

Ana Maria Souza dos Santos Moreau, Liovando Marciano da Costa, João Carlos Ker, Felipe Haenel Gomes

01/Dec/2006

The genesis of cohesive horizons in some soils is not well known yet and, in many cases, it is conflicting. The purpose of this study was to evaluate physical, chemical and mineralogical mechanisms that cause hardening in soils with cohesive horizons, fragipan and duripan in Brazilian Coastal Plain soils. Soil samples of two toposequences were sampled and the taxonomic classes of the soils were identified as Argisolic Eutrophic Red Latosol, Latosolic Dystrophic Yellow Argisol for the first toposequence, and Abruptic […]

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