3290 results

GROUPS OF INCEPTISOL PEDONS BASED ON CHEMICAL AND PHYSICAL PROPERTIES APPLYING MULTIVARIATE STATISTICS

Pablo Grahl dos Santos, Ildegardis Bertol, David José Miquelluti, Jaime Antônio Almeida, Álvaro Luiz Mafra

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 […]

EFFECTS OF COMPACTION DUE TO MACHINERY TRAFFIC ON SOIL PORE CONFIGURATION

Carlos Germán Soracco, Luis Alberto Lozano, Rafael Villarreal, Telmo Cecilio Palancar, Daniel Jorajuria Collazo, Guillermo Oliveiro Sarli, [...]

01/Mar/2015

Soil compaction has been recognized as a severe problem in mechanized agriculture and has an influence on many soil properties and processes. Yet, there are few studies on the long-term effects of soil compaction, and the development of soil compaction has been shown through a limited number of soil parameters. The objectives of this study were to evaluate the persistence of soil compaction effects (three traffic treatments: T0, without traffic; T3, three tractor passes; and T5, five tractor passes) on […]

DEVELOPMENT, AUTOMATION AND PERFORMANCE OF A CONSOLIDOMETER WITH HUMAN-MACHINE INTERFACE

Reginaldo Barboza da Silva, Batista Masqueto Junior, Kléber Pereira Lanças, Francisca Alcivania de Melo Silva

01/Mar/2015

To run a consolidation test, it is necessary to use a consolidometer. This equipment, however, had not been produced and sold in Brazil until some years ago. Non-automatic models available for import, although of low cost, are nevertheless rustic and need continuous calibration of pressure levels during the consolidation test. The exclusiveness and intervention of a technician throughout the test, associated with the precarious acquisition of data in these models, are still major factors that have made consolidation of this […]

EFFECT OF RICE STRAW AND NITRATE LEVELS IN SOIL SOLUTION ON NITROUS OXIDE EMISSION

André Carlos Cruz Copetti, Leandro Souza da Silva, Gerson Laerson Drescher, Eduardo Augusto Müller, Rafael Lago Busanello, Frederico Costa Beber Vieira

01/Mar/2015

Among the greenhouse gases, nitrous oxide (N2O) is considered important, in view of a global warming potential 296 times greater than that of carbon dioxide (CO2) and its dynamics strongly depend on the availability of C and mineral N in the soil. The understanding of the factors that define emissions is essential to develop mitigation strategies. This study evaluated the dynamics of N2O emissions after the application of different rice straw amounts and nitrate levels in soil solution. Pots containing […]

EFFICIENCY OF THE DENSE SOLUTIONS IN PHYSICAL FRACTIONATION OF SOIL ORGANIC MATTER

Paulo Cesar Conceição, Madalena Boeni, Cimélio Bayer, Jeferson Dieckow, Julio Cesar Salton, Cecilia Estima Sacramento dos Reis

01/Mar/2015

The mechanisms of stabilization of organic matter (OM) have been studied in Brazilian tropical and subtropical soils; however, few studies have evaluated the influence of the methodological part of the use of the solutions in the results. The aim of this study was to evaluate the efficiency of two salt solutions (1.8 kg dm-3 sodium iodide – NaI, and 2.0 kg dm-3 sodium polytungstate – SPT) in separation of densimetric soil organic matter (SOM) fractions in two soils (Acrisol from […]

CHARACTERIZATION OF HEADWATERS PEATS OF THE RIO ARAÇUAÍ, MINAS GERAIS STATE, BRAZIL

Diêgo Faustolo Alves Bispo, Alexandre Christofaro Silva, Cristiano Christofaro, Max Leandro Naves Silva, Maurício Soares Barbosa, Bárbara Pereira Christofaro Silva, [...]

01/Mar/2015

Peatlands are soil environments that accumulate water and organic carbon and function as records of paleo-environmental changes. The variability in the composition of organic matter is reflected in their morphological, physical, and chemical properties. The aim of this study was to characterize these properties in peatlands from the headwaters of the Rio Araçuaí (Araçuaí River) in different stages of preservation. Two cores from peatlands with different vegetation types (moist grassland and semideciduous seasonal forest) from the Rio Preto [Preto River] […]

WATER INFILTRATION IN TWO CULTIVATED SOILS IN SOUTHERN BRAZIL

Ildegardis Bertol, Fabrício Tondello Barbosa, Camilo Bertol, Rodrigo Vieira Luciano

01/Mar/2015

Infiltration is the passage of water through the soil surface, influenced by the soil type and cultivation and by the soil roughness, surface cover and water content. Infiltration absorbs most of the rainwater and is therefore crucial for planning mechanical conservation practices to manage runoff. This study determined water infiltration in two soil types under different types of management and cultivation, with simulated rainfall of varying intensity and duration applied at different times, and to adjust the empirical model of […]

INTERNAL STRUCTURE OF A VERMICULAR IRONSTONE AS DETERMINED BY X-RAY COMPUTED TOMOGRAPHY SCANNING

Yuri Lopes Zinn, Carla Eloize Carducci, Marla Alessandra Araujo

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 […]

PHYTOAVAILABILITY OF COPPER IN INDUSTRIAL BY-PRODUCTS AND MINERAL FERTILIZERS

Camila Prado Cenciani de Souza, Cleide Aparecida de Abreu, José Francisco da Cunha, Geraldo Magela da Costa, Cristiano Alberto de Andrade

01/Mar/2015

Alternative copper (Cu) sources could be used in fertilizer production, although the bioavailability of copper in these materials is unknown. The objective of this study was to evaluate the extractants neutral ammonium citrate (NAC), 2 % citric acid, 1 % acetic acid, 10 % HCl, 10 % H2SO4, buffer solution pH 6.0, DTPA, EDTA, water, and hot water in the quantification of available Cu content in several sources, relating them to the relative agronomic efficiency (RAE) of wheat grown in […]

FERTILIZER RECOMMENDATION SYSTEM FOR MELON BASED ON NUTRITIONAL BALANCE

José Aridiano Lima de Deus, Ismail Soares, Júlio César Lima Neves, José Francismar de Medeiros, Fábio Rodrigues de Miranda

01/Mar/2015

Melon is one of the most demanding cucurbits regarding fertilization, requiring knowledge of soils, crop nutritional requirements, time of application, and nutrient use efficiency for proper fertilization. Developing support systems for decision-making for fertilization that considers these variables in nutrient requirement and supply is necessary. The objective of this study was parameterization of a fertilizer recommendation system for melon (Ferticalc-melon) based on nutritional balance. To estimate fertilizer recommendation, the system considers the requirement subsystem (REQ), which includes the demand for […]

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