3312 results

Forms of phosphorus in an oxisol under different soil tillage systems and cover plants in rotation with maize

Arminda Moreira de Carvalho, Mercedes Maria da Cunha Bustamante, Zayra Azeredo do Prado Almondes, Cícero Célio de Figueiredo

01/Jun/2014

Phosphorus fractions play a key role in sustaining the productivity of acid-savanna Oxisols and are influenced by tillage practices. The aim of this study was to quantify different P forms in an Oxisol (Latossolo Vermelho-Amarelo) from the central savanna region of Brazil under management systems with cover crops in maize rotation. Three cover crops (Canavalia brasiliensis, Cajanus cajan (L.), and Raphanus sativus L.) were investigated in maize rotation systems. These cover crops were compared to spontaneous vegetation. The inorganic forms […]

Compared performance of penetrometers and effect of soil water content on penetration resistance measurements

Edison Aparecido Mome Filho, Alvaro Pires da Silva, Getulio Coutinho Figueiredo, Fernando Henrique Setti Gimenes, André Cesar Vitti

01/Jun/2014

Modern agriculture techniques have a great impact on crops and soil quality, especially by the increased machinery traffic and weight. Several devices have been developed for determining soil properties in the field, aimed at managing compacted areas. Penetrometry is a widely used technique; however, there are several types of penetrometers, which have different action modes that can affect the soil resistance measurement. The objective of this study was to compare the functionality of two penetrometry methods (manual and automated mode) […]

Identifying sources of sediment production in a hillside catchment area

Pablo Miguel, Ricardo Simão Diniz Dalmolin, Fabrício de Araújo Pedron, Jean Michel Moura-Bueno, Tales Tiecher

01/Apr/2014

Land use outside of its agricultural suitability is the main cause of degradation of natural resources due to anthropogenic activities. Agricultural activities are among those that most disturb the environment, exposing the soil to the action of water erosion and accelerating the transfer of sediments into bodies of water. In recent years, the fingerprinting method for identifying sources of sediment has been successfully used throughout the world; however, such studies in Brazil are still incipient. This study aims to estimate […]

Pedogenesis and classification of latosols developed from itabirites in the region of Quadrilátero Ferrífero in Minas Gerais

Samuel Ângelo Diógenes Costa, João Carlos Ker, Diana Ferreira de Freitas Simões, Maurício Paulo Ferreira Fontes, José Domingos Fabris, Felipe Vaz Andrade

01/Apr/2014

Located in the Midwest of the State of Minas Gerais, a region called Quadrilátero Ferrífero covers an area of approximately 7,000 km2. Since the seventeenth century, it is known as gold- and iron-producing province, and the geological context is therefore one of the best-studied of Brazil. The regional topography is very rugged, with mostly poorly developed pedogenesis, especially Cambissolos Háplicos, Neossolos Litólicos and Neossolos Regolíticos. In a smaller proportion and on colluvial ramps (hilly relief), very Fe-rich Latossolos Vermelhos occur, […]

Quality of surface water related to land use: a case study in a catchment with small farms and intensive vegetable crop production in southern Brazil

Karina Hacke Ribeiro, Nerilde Favaretto, Jeferson Dieckow, Luiz Cláudio de Paula Souza, Jean Paolo Gomes Minella, Luciano de Almeida, [...]

01/Apr/2014

Water degradation is strongly related to agricultural activity. The aim of this study was to evaluate the influence of land use and some environmental components on surface water quality in the Campestre catchment, located in Colombo, state of Parana, Brazil.  Physical and chemical attributes were analyzed (total nitrogen, ammonium, nitrate, total phosphorus, electrical conductivity, pH, temperature, turbidity, total solids, biological oxygen demand, chemical oxygen demand and dissolved oxygen). Monthly samples of the river water were taken over one year at […]

Using numerical classification of profiles based on Vis-NIR spectra to distinguish soils from the Piracicaba Region, Brazil

Rodnei Rizzo, José A. M. Demattê, Fabrício da Silva Terra

01/Apr/2014

Considering that information from soil reflectance spectra is underutilized in soil classification, this paper aimed to evaluate the relationship of soil physical, chemical properties and their spectra, to identify spectral patterns for soil classes, evaluate the use of numerical classification of profiles combined with spectral data for soil classification. We studied 20 soil profiles from the municipality of Piracicaba, State of São Paulo, Brazil, which were morphologically described and classified up to the 3rd category level of the Brazilian Soil […]

Geostatistics in assessment of physical properties in a latossolo (oxisol) under native forest and grassland in Manicoré, Amazonas, Brazil

Renato Eleotério de Aquino, Milton César Costa Campos, José Marques Júnior, Ivanildo Amorim de Oliveira, Bruno Campos Mantovaneli, Marcelo Dayron Rodrigues Soares

01/Apr/2014

The use of geostatistical techniques allows detection of the existence of dependence and the spatial distribution of soil properties, thus constituting an important tool in the analysis and detailed description of the behavior of soil physical properties. The aim of the present study was to use geostatistics in assessment of physical properties in a Latossolo (Oxisol) dystrophic under native forest and pasture in the Amazon region of Manicore. Grids with of 70 x 70 m were established in native forest […]

Hydrological processes obtained on the plot scale under four simulated rainfall tests during the cycle of different crop systems

Ildegardis Bertol, Roger Robert Ramos, Fabrício Tondello Barbosa, Julio César Ramos, Douglas Henrique Bandeira, Mitsui Shinosaka Tanaka

01/Apr/2014

The cropping system influences the interception of water by plants, water storage in depressions on the soil surface, water infiltration into the soil and runoff. The aim of this study was to quantify some hydrological processes under no tillage cropping systems at the edge of a slope, in 2009 and 2010, in a Humic Dystrudept soil, with the following treatments: corn, soybeans, and common beans alone; and intercropped corn and common bean. Treatments consisted of four simulated rainfall tests at […]

Estimation of soil water infiltration at the catchment scale

Cláudia Alessandra Peixoto de Barros, Jean Paolo Gomes Minella, Rutinéia Tassi, Leandro Dalbianco, Anaí Sangiovo Ottonelli

01/Apr/2014

The spatial variability of soil characteristics makes the estimation of water infiltration highly dependent on the scale of analysis. Many studies require information on the dynamics of infiltration to describe the dynamics of other processes associated with water, sediment and solutes. This study aims to use two methodological strategies to estimate water infiltration at the catchment scale. The parameters of two infiltration models were fitted to a data set collected over two years of monitoring (77 rainfall-runoff events) occurring under […]

Arbuscular mycorrhizal fungal communities and soil aggregation as affected by cultivation of various crops during the sugarcane fallow period

Priscila Viviane Truber, Carolina Fernandes

01/Apr/2014

Management systems involving crop rotation, ground cover species and reduced soil tillage can improve the soil physical and biological properties and reduce degradation. The primary purpose of this study was to assess the effect of various crops grown during the sugarcane fallow period on the production of glomalin and arbuscular mycorrhizal fungi in two Latosols, as well as their influence on soil aggregation. The experiment was conducted on an eutroferric Red Latosol with high-clay texture (680 g clay kg-1) and […]

1 88 89 90 91 92 332