3290 results

Cycling of nutrients and silicon in pigeonpea and pearl millet monoculture and intercropping

Carlos Alexandre Costa Crusciol, Jayme Ferrari Neto, Rogério Peres Soratto, Claudio Hideo Martins da Costa

01/Dec/2013

In a no-tillage system, cover crops must be used that combine shoot dry matter production and nutrient recycling. The aim of this study was to evaluate shoot dry matter production, decomposition rate and macronutrient and silicon release from pigeonpea and pearl millet in monoculture and intercropping systems. A randomized block design was used with a 3 x 6 factorial arrangement, with four replications. The first factor consisted of three cover crops (pigeonpea, pearl millet and intercropping of these cover crops) […]

Chemical and biological properties of phosphorus-fertilized soil under legume and grass cover (Cerrado region, Brazil)

Marcelo Fernando Pereira Souza, Mariana Pina da Silva, Orivaldo Arf, Ana Maria Rodrigues Cassiolato

01/Dec/2013

The use of cover crops has been suggested as an effective method to maintain and/or increase the organic matter content, while maintaining and/or enhancing the soil physical, chemical and biological properties. The fertility of Cerrado soils is low and, consequently, phosphorus levels as well. Phosphorus is required at every metabolic stage of the plant, as it plays a role in the processes of protein and energy synthesis and influences the photosynthetic process. This study evaluated the influence of cover crops […]

Land use on the microbial quality of soil aggregates of a Red Yellow Latosol

Rogério Melloni, Eliane Guimarães Pereira Melloni, Lucas Lopes Vieira

01/Dec/2013

Most studies related to soil aggregation associate the effect of managements or land use types with the organic matter content. However, a direct evaluation of microorganisms and their processes in undisturbed soil allows a better understanding of the real effect of different managements. The objective of this study was to evaluate the changes induced by different types of land use (pasture, eucalyptus forest, araucaria forest, conventional tillage with carrot, and conventional tillage with pumpkin) on soil chemical properties (pH, Ca, […]

Upland rice under no-tillage preceded by crops for soil cover and nitrogen fertilization

Edemar Moro, Carlos Alexandre Costa Crusciol, Heitor Cantarella, Adriano Stephan Nascente

01/Dec/2013

The grain yield of upland rice under no-tillage has been unsatisfactory and one reason could be the nitrate/ammonium balance in the soil. Cover crops and nitrogen fertilization can be used to change the nitrate/ammonium relation in the soil and improve conditions for the development of upland rice in the no-tillage (NT) system. The aim was to study the effect of cover crops and nitrogen sources on grain yield of upland rice under no tillage. The study was carried out on […]

Influence of planting systems on dendrometric properties and soil fauna in an area degraded by clay extraction

Cristiane Figueira da Silva, Marco Antônio Martins, Eliane Maria Ribeiro da Silva, Marcos Gervasio Pereira, Maria Elizabeth Fernandes Correia

01/Dec/2013

The intercropping of Eucalyptus with legumes can promote an improvement of soil biological quality in degraded areas and also be advantageous for the species of the consortium. The aim of this study was to evaluate the influence of planting systems (monoculture and consortium) of Acacia mangium (AM), Sesbania virgata (SV) and Eucalyptus camaldulensis (EC) on the biological characteristics of the plants (dendrometric attributes) and specifically on the fauna in the litter and the surface soil layer (0-0.05 m). An experiment […]

Behavior of iron oxides in the clay fraction and adsorbed phosphorus under different sugarcane cultivation systems

Diogo Mazza Barbieri, José Marques Júnior, Gener Tadeu Pereira, Newton La Scala Jr., Diego Silva Siqueira, Alan Rodrigo Panosso

01/Dec/2013

In agriculture, the search for higher crop yields based on sustainable soil management has led to a gradual pursuit of knowledge of the variables related to production systems. The identification of the causes of variability of these properties has become a part of strategic planning in the sugar and ethanol industry. This study investigated the spatial variability of iron oxides in the clay fraction and its relationship to soil physical and chemical properties in different sugarcane cultivation systems in the […]

Effect of soil tillage and sugarcane trash on CO2 emission

Mara Regina Moitinho, Milton Parron Padovan, Alan Rodrigo Panosso, Newton La Scala Jr

01/Dec/2013

The soil is one of the main C pools in terrestrial ecosystem, capable of storing significant C amounts. Therefore, understanding the factors that contribute to the loss of CO2 from agricultural soils is critical to determine strategies reducing emissions of this gas and help mitigate the greenhouse effect. The purpose of this study was to investigate the effect of soil tillage and sugarcane trash on CO2 emissions, temperature and soil moisture during sugarcane (re)planting, over a study period of 15 […]

Sugarcane trash management assessed by the interaction of yield with soil properties

Flávio Carlos Dalchiavon, Morel de Passos e Carvalho, Rafael Montanari, Marcelo Andreotti, Edjair Augusto Dal Bem

01/Dec/2013

Currently, sugarcane plays an important global role, particularly with a view to alternative energy sources. Thus, in a sugarcane field of the mill Vale do Paraná S/A Álcool e Açúcar, Rubineia, São Paulo State, managed under two green cane harvest systems (cane trash left on and cane trash removed from the soil), Pearson and spatial correlations between the sugarcane yield (variety RB855035 in the third cut) and soil physical and chemical properties were studied to identify the property best correlated […]

Water retention and availability in soils of the State of Santa Catarina-Brazil: effect of textural classes, soil classes and lithology

André da Costa, Jackson Adriano Albuquerque, Adriano da Costa, Patricia Pértile, Franciani Rodrigues da Silva

01/Dec/2013

The retention and availability of water in the soil vary according to the soil characteristics and determine plant growth. Thus, the aim of this study was to evaluate water retention and availability in the soils of the State of Santa Catarina, Brazil, according to the textural class, soil class and lithology. The surface and subsurface horizons of 44 profiles were sampled in different regions of the State and different cover crops to determine field capacity, permanent wilting point, available water […]

Structural and magnetic characterization of maghemites prepared from Al-substituted magnetites

Marcelo Augusto Batista, Antonio Carlos Saraiva da Costa, Jerry Marshal Bigham, Andrea Paesano Junior, Graciele Berndt, Tadeu Takeyoshi Inoue, [...]

01/Dec/2013

Synthetic aluminum-substituted maghemites were characterized by total chemical analysis, powder X-ray diffraction (XRD), Mössbauer spectroscopy (ME), and vibrating sample magnetometry (VSM). The aim was to determine the structural, magnetic, and hyperfine properties of γ-Fe2-xAlxO3 as the Al concentration is varied. The XRD results of the synthetic products were indexed exclusively as maghemite. Increasing Al for Fe substitution decreased the mean crystalline dimension and shifted all diffraction peaks to higher o2θ angles. The a0 dimension of the cubic unit cell decreased […]

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