PRODUCTION OF A SOIL MAP ASSOCIATING COMMON DIGITAL SOIL MAPPING TECHNIQUES WITH HAND DELINEATION OF SOIL MAPPING UNITS
01/Jul/2015
The production of soil maps through digital soil mapping (DSM) techniques may be hampered due to the lack of traditional reference soil maps. In these situations, the tacit knowledge of the field soil scientist can be used for manual delineation of soil mapping units (MUs) based on generation of a map of occurrence of soil types predicted by DSM. The objective of this study was to evaluate and to compare soil maps generated by two methods. One method, called “direct […]
SELECTION OF SAMPLING DENSITY BASED ON DATA FROM AREAS ALREADY MAPPED FOR TRAINING DECISION TREE MODELS IN DIGITAL SOIL MAPPING
01/Jul/2015
In order to study sampling techniques useful for digital soil mapping (DSM), we evaluated the effect of changes in sampling density, based on data from areas already mapped by traditional methods, in regard to the accuracy of decision trees models for generating soil maps using DSM. In two watersheds in northwestern Rio Grande do Sul, Brazil, 1:50,000 scale conventional soils maps were used as reference maps. From the ASTER – GDEM Global Digital Elevation Model and the hydrographic network, maps […]
MATHEMATICAL TOOLS ASSOCIATED WITH MAGNETIC SUSCEPTIBILITY AND LANDSCAPE MODELS IN IDENTIFYING AREAS FOR SPECIFIC MANAGEMENT PRACTICES
01/Jul/2015
The identification of variability patterns through soil properties allows land use and occupation in a sustainable manner. The aim of this study was to ascertain the potential of magnetic susceptibility of the soil and landscape models in defining areas for specific management practices through the use of mathematical tools. The study area is in the municipality of Guariba, SP, Brazil. We chose an area of 110 ha in which three geomorphic surfaces (I, II, and III) had been identified and […]
Boundary between Soil and Saprolite in Alisols in the South of Brazil
01/May/2015
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 […]
Planosols and Gleysols Used in the Manufacture of Handcrafted Pottery in the Semiarid Region of Minas Gerais
01/May/2015
Ethnopedological knowledge has provided important information about the way of life of rural people and their traditions, like the craft of making pieces of pottery from suitable soils. The objective of this study was to evaluate the physical, chemical, and mineralogical properties of Planosols and Gleysols used in the production of handcrafted pottery artifacts in the State of Minas Gerais, Brazil. In the clay pits, two profiles of Planosol soil (P1 and P2) and one of Gleysol soil (P3) used […]
Spatial Variability and Sampling Density of Magnetic Susceptibility and Soil Properties in Ultisols of the Manicoré Region, AM, Brazil
01/May/2015
The difficulty in finding recent information on the spatial behavior of properties of soils in the Brazilian Amazon region has been a concern of many researchers. Due to the great difficulty and costs in assessing soil properties, alternative methods have been used for prediction, such as magnetic susceptibility. Thus, the objective of this study was to evaluate the spatial variability of magnetic susceptibility and of physical and chemical soil properties in an Argissolo Vermelho (Ultisol) from native forest, Archaeological Black […]
Spatial Variability and Sampling Density of Magnetic Susceptibility and Soil Properties in Ultisols of the Manicoré Region, AM, Brazil
01/May/2015
The difficulty in finding recent information on the spatial behavior of properties of soils in the Brazilian Amazon region has been a concern of many researchers. Due to the great difficulty and costs in assessing soil properties, alternative methods have been used for prediction, such as magnetic susceptibility. Thus, the objective of this study was to evaluate the spatial variability of magnetic susceptibility and of physical and chemical soil properties in an Argissolo Vermelho (Ultisol) from native forest, Archaeological Black […]
Spatial Variability and Sampling Density of Magnetic Susceptibility and Soil Properties in Ultisols of the Manicoré Region, AM, Brazil
01/May/2015
The difficulty in finding recent information on the spatial behavior of properties of soils in the Brazilian Amazon region has been a concern of many researchers. Due to the great difficulty and costs in assessing soil properties, alternative methods have been used for prediction, such as magnetic susceptibility. Thus, the objective of this study was to evaluate the spatial variability of magnetic susceptibility and of physical and chemical soil properties in an Argissolo Vermelho (Ultisol) from native forest, Archaeological Black […]
GROUPS OF INCEPTISOL PEDONS BASED ON CHEMICAL AND PHYSICAL PROPERTIES APPLYING MULTIVARIATE STATISTICS
01/Mar/2015
In a soil survey, a detailed description of a set of soil properties is important for analyzing and understanding the interactions of several soil forming processes. Thus, multivariate analysis may be an important statistical tool to better interpret and understand the relationships and similarities between pedons. The aim of this study was to differentiate and group similar pedons based on physical and chemical properties using multivariate statistics. The study was carried out in Lages, SC, Brazil, at 27º 48’ S […]
INTERNAL STRUCTURE OF A VERMICULAR IRONSTONE AS DETERMINED BY X-RAY COMPUTED TOMOGRAPHY SCANNING
01/Mar/2015
Ironstones or petroplinthites are common materials in soils under humid tropical climate, generally defined as the result of Fe oxide accumulation in areas where the water table oscillates, and may exhibit considerable morphological variability. The aim of this study was to examine the internal structure and porosity of an ironstone fragment from a Petroferric Acrudox in Minas Gerais, Brazil, by computed tomography (CT) and conventional techniques. The sample analyzed had total porosity of 59.5 %, with large macropores in the […]