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192 results

Functionalized Charcoal as a Buffering Matrix of Copper and Zinc Availability

Gelton Geraldo Fernandes Guimarães, Amanda Soares Giroto, Breno Cardoso Teixeira, Leonardus Vergütz, Reinaldo Bertola Cantarutti

02/Nov/2018

ABSTRACT: High copper (Cu) and zinc (Zn) contents in soil can cause phytotoxicity to plants and contaminate surface and groundwater, with negative effects on agriculture and the environment. Functionalized charcoal (OCh) has high cation exchange capacity (CEC) and the ability to adsorb Cu and Zn and control their availability in the soil and water. An adsorption study at two pH levels was carried out to evaluate increasing Cu and Zn sorption capacity provided by the functionalization process of a charcoal. […]

Potassium Dynamics in Ruzigrass Rhizosphere

Marcelo Raphael Volf, Tiara Moraes Guimarães, Daniele Scudeletti, Igor Vilela Cruz, Ciro Antonio Rosolem

02/Nov/2018

ABSTRACT: Ruzigrass (Urochola ruziziensis) has a large capacity to take up K from the soil, including non-exchangeable forms, and can play an important role in nutrient cycling in integrated production systems. However, K transport to roots of brachiarias is not well known, nor the nutrient dynamics in the rhizosphere, where a concentration gradient may be established towards the non-rhizospheric soil, creating a favorable environment for the release of non-exchangeable K. This study aimed to evaluate the effect of ruzigrass on […]

Long-Term Effect of Soil Use and Management on Organic Carbon and Aggregate Stability

Neuro Hilton Wolschick, Fabrício Tondello Barbosa, Ildegardis Bertol, Bárbara Bagio, Danieli Schneiders Kaufmann

05/Sep/2018

ABSTRACT: The conversion of native grassland into farmland causes changes in the soil. Tillage has profound effects on soil organic matter. The intensification of soil tillage decreases soil quality by reducing aggregate stability. Soil aggregate stability and soil organic matter are key indicators for soil quality and environmental sustainability in agro-ecosystems. The aim of the present study is to evaluate the total organic carbon content and the physical and chemical fractions of the organic matter in a soil under different […]

Root and Shoot Contribution to Carbon and Nitrogen Inputs in the Topsoil Layer in No-Tillage Crop Systems under Subtropical Conditions

Marciel Redin, Sylvie Recous, Celso Aita, Bruno Chaves, Ismael Cristiano Pfeifer, Leonardo Mendes Bastos, [...]

31/Jul/2018

ABSTRACT Recycling of carbon (C) and nitrogen (N) from plants into soils is decisive for maintaining soil organic matter and soil fertility. Therefore, we quantified plant biomass and C and N in the shoots and roots from the topsoil layer for a wide range of annual crops grown under subtropical conditions. We grew 26 species, 13 main crops, and 13 cover crops, in the field in standard sowing arrangements. Root biomass was recovered from the 0.00-0.20 m soil layer at […]

Rhizophagus Clarus and Phosphorus in Crotalaria juncea: Growth, Glomalin Content and Acid Phosphatase Activity in a Copper-Contaminated Soil

Paulo Ademar Avelar Ferreira, Carlos Alberto Ceretta, Tales Tiecher, Daniela Basso Facco, Luana Paula Garlet, Cláudio Roberto Fonsêca Sousa Soares, [...]

23/Jul/2018

ABSTRACT Crotalaria juncea is used as plant cover in grape vineyards in Brazil, which usually present soils with high copper (Cu) levels due to the application of Cu-based phyto-sanitary products. Under this condition an increase growth and cover of C. juncea is needed to improve the phytoremediation processes in those soils. Some alternatives to achieve this condition is the inoculation with arbuscular mycorrhizal fungi (AMF), which has demonstrated an important increase of plant growth in Cu-contaminated soils at different soil […]

Cattle Manure Bioconversion Effect on the Availability of Nitrogen, Phosphorus, and Potassium in Soil

Daniel Pazzini Eckhardt, Marciel Redin, Natielo Almeida Santana, Lessandro De Conti, Jorge Dominguez, Rodrigo Josemar Seminoti Jacques, [...]

23/Jul/2018

ABSTRACT The efficiency index (EI) refers to the ratio of nutrients mineralized/made available in the soil to the total amount of nutrients added by organic fertilizer. Therefore, understanding the EI is essential for recommendation of organic fertilization. The aim of this study was to evaluate the availability through mineralization and the efficiency index of nitrogen (N), phosphorus (P), and potassium (K) in organic fertilizers produced from cattle manure. The following treatments were evaluated in an incubation experiment under controlled conditions: […]

Biometric Responses of Soybean to Different Potassium Fertilization Management Practices in Years with High and Low Precipitation

Michel Esper Neto, Evandro Antonio Minato, Marcos Renan Besen, Tadeu Takeyoshi Inoue, Marcelo Augusto Batista

17/Jul/2018

ABSTRACT Brazilian soybean producers commonly apply maintenance potassium (K) fertilization during cultivation to restore the K taken up by plants; however, this measure can modify the morphophysiological plant characteristics, since the functions of K are closely related with plant growth and development. This study assessed the morphological changes in soybean plants in response to K rates, sowing fertilization, and the application periods of K fertilization in a Latossolo Vermelho eutroférrico (Oxisol) under a no-tillage system, located in the municipality of […]

Daycent Simulation of Methane Emissions, Grain Yield, and Soil Organic Carbon in a Subtropical Paddy Rice System

Douglas Adams Weiler, Carlos Gustavo Tornquist, Tiago Zschornack, Stephen Michael Ogle, Filipe Selau Carlos, Cimélio Bayer

18/Jun/2018

ABSTRACT The DayCent ecosystem model, widely tested in upland agroecosystems, was recently updated to simulate waterlogged soils. We evaluated the new version in a paddy rice experiment in Southern Brazil. DayCent was used to simulate rice yield, soil organic carbon (SOC), and soil CH4 fluxes. Model calibration was conducted with a multiple-year dataset from the conventional tillage treatment, followed by a validation phase with data from the no-tillage treatment. Model performance was assessed with statistics commonly used in modeling studies: […]

Surface Application of Lime on a Guava Orchard in Production

Márcio Cleber de Medeiros Corrêa, William Natale, Renato de Mello Prado, David Ariovaldo Banzatto, Ronialison Fernandes Queiroz, Marcos Antonio Camacho da Silva

18/Jun/2018

ABSTRACT Several complications can arise, either directly or indirectly, from implementation of measures to correct soil acidity in established fruit orchards, such as impaired roots, lower root volume, risk of plant infection, propagation of diseases, promotion of pest development (especially nematodes), and soil disaggregation and compaction. These factors can have a negative effect on crop yield. Therefore, it becomes critical to implement an effective method of neutralizing soil acidity, especially at the level of the tree roots. To assess the […]

Geochemistry and Spatial Variability of Rare Earth Elements in Soils under Different Geological and Climate Patterns of the Brazilian Northeast

Cinthia Maria Cordeiro Atanázio Cruz Silva, Ronny Sobreira Barbosa, Clístenes Williams Araújo do Nascimento, Yuri Jacques Agra Bezerra da Silva, Ygor Jacques Agra Bezerra da Silva

18/Jun/2018

ABSTRACT Growth in the agricultural and industrial sectors has increased the demand for rare earth elements (REEs) in the production of technological devices and fertilizers. Thus, the accumulation of these elements in the soil has become an environmental concern. Here, we aim to determine the natural contents of REEs in soils derived from different parent materials and under climatic conditions ranging from humid to semi-arid. We then evaluate the influence of major elements and soil properties on the geochemistry of […]

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