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55 results

Physical, Chemical, and Microbiological Properties of Soil under Different Plant Covers in the Seridó Desertification Region in the Brazilian Semiarid

Adriana Ferreira Martins, Ignácio Hernan Salcedo, Flávio Pereira de Oliveira ORCID logo , Walter Esfrain Pereira

08/Mar/2019

ABSTRACT The Seridó Desertification Region is a result of inadequate management of the native Caatinga vegetation, which generated degraded areas with little or no capacity for plant production. The area has experienced a succession of different land uses, but little is known about the impact of these changes. The present study tested the hypothesis that the intense degradation of the Caatinga drastically decreased vegetal biomass production, which favored direct soil exposure and resulted in a lower abundance and diversity of […]

Phosphorus Fractions in Soil with Organic and Mineral Fertilization in Integrated Crop-Livestock System

Amanda Zolet Rigo, Juliano Corulli Corrêa ORCID logo , Álvaro Luiz Mafra, Paulo Hentz, Marco André Grohskopf, Luciano Colpo Gatiboni, [...]

06/Feb/2019

ABSTRACT Use of organic fertilizers in integrated crop-livestock (iCL) systems may affect soil phosphorus fractions. This study aimed to determine phosphorus fractions in the soil under the iCL system after six years of application of organic or mineral fertilizers. The experiment was conducted on a Rhodic Kandiudox (Nitossolo Vermelho Distroférrico) in a randomized block design, using a 5 × 3 + 1 factorial scheme, with four replicates. The treatments consisted of three organic fertilizers (poultry litter, pig slurry, and compost) […]

Cacao Crop Management Zones Determination Based on Soil Properties and Crop Yield

Perla Silva Matos de Carvalho, Laís Barreto Franco, Samuel de Assis Silva, George Andrade Sodré, Daniel Marçal de Queiroz, Julião Soares de Souza Lima

12/Dec/2016

ABSTRACT: The use of management zones has ensured yield success for numerous agricultural crops. In spite of this potential, studies applying precision agricultural techniques to cacao plantations are scarce or almost nonexistent. The aim of the present study was to delineate management zones for cacao crop, create maps combining soil physical properties and cacao tree yield, and identify what combinations best fit within the soil chemical properties. The study was conducted in 2014 on a cacao plantation in a Nitossolo […]

NUTRIENT AVAILABILITY AND RECOVERY FROM CROP RESIDUES IN SOIL WITH DIFFERENT TEXTURES

Henrique José Guimarães Moreira Maluf, Emanuelle Mercês Barros Soares, Ivo Ribeiro da Silva, Júlio César Lima Neves, Mailson Félix de Oliveira Silva

01/Dec/2015

ABSTRACT Crop residues on the soil surface not only provide physical protection but may release significant amounts of nutrients to the soil through decomposition. However, the availability of these nutrients to plants has not been sufficiently studied. The aim of this study was to evaluate the total contents of organic C and N, pH, and the availability and recovery rate of P, K, Ca, Mg, and S from the biogeochemical cycling of different crop residues over time in built soils […]

Chemical and Biochemical Properties of Oxisols after Sewage Sludge Application for 16 Years

Marcela Midori Yada, Wanderley José de Melo, Fábio Luiz Checchio Mingotte, Valéria Peruca de Melo, Gabriel Maurício Peruca de Melo

01/Sep/2015

ABSTRACT The large production of sewage sludge (SS), especially in large urban centers, has led to the suggestion of using this waste as fertilizer in agriculture. The economic viability of this action is great and contributes to improve the environment by cycling the nutrients present in this waste, including high contents of organic matter and plant nutrients. This study evaluated the chemical and biochemical properties of Dystrophic and Eutroferric Latossolos Vermelhos (Oxisols) under corn and after SS application at different […]

Sustainability of Wood Productivity of Pinus Taeda Based on Nutrient Export and Stocks in the Biomass and in the Soil

Ricardo Michael de Melo Sixel, José Carlos Arthur, José Leonardo de Moraes Gonçalves, Clayton Alcarde Alvares, Gabriel Ramatis Pugliese Andrade, Antonio Carlos Azevedo, [...]

01/Sep/2015

ABSTRACT The impact of intensive management practices on the sustainability of forest production depends on maintenance of soil fertility. The contribution of forest residues and nutrient cycling in this process is critical. A 16-year-old stand of Pinus taeda in a Cambissolo Húmico Alumínico léptico (Humic Endo-lithic Dystrudept) in the south of Brazil was studied. A total of 10 trees were sampled distributed in five diameter classes according to diameter at breast height. The biomass of the needles, twigs, bark, wood, […]

Soil phosphorus availability and soybean response to phosphorus starter fertilizer

Ciro Antonio Rosolem, Alexandre Merlin

01/Oct/2014

Phosphorus fixation in tropical soils may decrease under no-till. In this case, P fertilizer could be surface-spread, which would improve farm operations by decreasing the time spend in reloading the planter with fertilizers. In the long term, less soluble P sources could be viable. In this experiment, the effect of surface-broadcast P fertilization with both soluble and reactive phosphates on soil P forms and availability to soybean was studied with or without fertilization with soluble P in the planting furrow […]

Soil chemical atributes associated with wheat yield in a plot with different yield potentials

Luiz Fernando Machado Kramer, Marcelo Marques Lopes Müller, Cassio Antônio Tormena, Aline Marques Genú, Leandro Michalovicz, Marcelo Vicensi

01/Aug/2014

Different yield potentials between plots and within them have been verified in areas managed under no-till (NT). Precision farming (PF) techniques can help in identifying these distinct areas, but for efficient soil fertility management in areas under long-term NT, there must be representative sampling. The aim of this study was to evaluate the influence of soil chemical properties on wheat yield in accordance with the sampling layer or depth in an area under long-term NT using zones of a plot […]

Efficiency of nitrogen fertilizer applied at corn sowing in contrasting growing seasons in Paraguay

Telmo Jorge Carneiro Amado, Enrique Oswin Hahn Villalba, Rafael Pivotto Bortolotto, Antônio Luis Santi, Enrique Asterio Benítez León, Dorothy Menefee, [...]

01/Dec/2013

In order to select soil management practices that increase the nitrogen-use efficiency (NUE) in agro-ecosystems, the different indices of agronomic fertilizer efficiency must be evaluated under varied weather conditions. This study assessed the NUE indices in no-till corn in southern Paraguay. Nitrogen fertilizer rates from 0 to 180 kg ha-1 were applied in a single application at corn sowing and the crop response investigated in two growing seasons (2010 and 2011). The experimental design was a randomized block with three […]

Optical crop sensor for variable-rate nitrogen fertilization in corn: i – plant nutrition and dry matter production

Jardes Bragagnolo, Telmo Jorge Carneiro Amado, Rodrigo da Silveira Nicoloso, Joerg Jasper, Junior Kunz, Tiago de Gregori Teixeira

01/Oct/2013

Variable-rate nitrogen fertilization (VRF) based on optical spectrometry sensors of crops is a technological innovation capable of improving the nutrient use efficiency (NUE) and mitigate environmental impacts. However, studies addressing fertilization based on crop sensors are still scarce in Brazilian agriculture. This study aims to evaluate the efficiency of an optical crop sensor to assess the nutritional status of corn and compare VRF with the standard strategy of traditional single-rate N fertilization (TSF) used by farmers. With this purpose, three […]

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