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	Provedor de dados AgEcon (2) Autor Davis, Victoria (2) Kupiec-Teahan, Beata (2) Leat, Philip M.K. (2) Milne, Anne (2) Revoredo-Giha, Cesar (2) Wrieden, Wendy (2) Mais... Palavra-chave Consumer choices (2) Food Consumption/Nutrition/Food Safety (2) Saturated fats (2) Sausages consumption (2) Scotland (2) Sodium (2) D1 (1) Mais... Tipo do documento Conference Paper or Presentation (1) Working or Discussion Paper (1) Ano 2010 (2) País United States (2) Idioma Inglês (2)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 159 Primeira ... 1 2 3 4 5 6 7 8 ... Última Geochemistry and Spatial Variability of Rare Earth Elements in Soils under Different Geological and Climate Patterns of the Brazilian Northeast Rev. Bras. Ciênc. Solo Silva,Cinthia Maria Cordeiro Atanázio Cruz; Barbosa,Ronny Sobreira; Nascimento,Clístenes Williams Araújo do; Silva,Yuri Jacques Agra Bezerra da; Silva,Ygor Jacques Agra Bezerra da. 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 REEs. The contents of REEs were determined using inductively coupled plasma optical emission spectroscopy. Major elements were determined by X-ray fluorescence spectrometry. The mean content of REEs in soils from Rio Grande do Norte (RN),... Tipo: Info:eu-repo/semantics/article Palavras-chave: Natural contents; Lanthanides; Geostatistics; Factor analysis; Soil quality. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100524 Local influence for spatial analysis of soil physical properties and soybean yield using student's t-distribution Rev. Bras. Ciênc. Solo Assumpção,Rosangela Aparecida Botinha; Opazo,Miguel Angel Uribe; Galea,Manuel. The modeling and estimation of the parameters that define the spatial dependence structure of a regionalized variable by geostatistical methods are fundamental, since these parameters, underlying the kriging of unsampled points, allow the construction of thematic maps. One or more atypical observations in the sample data can affect the estimation of these parameters. Thus, the assessment of the combined influence of these observations by the analysis of Local Influence is essential. The purpose of this paper was to propose local influence analysis methods for the regionalized variable, given that it has n-variate Student's t-distribution, and compare it with the analysis of local influence when the same regionalized variable has n-variate normal... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; EM algorithm; Spatial variability. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000600008 Spatial variability of soil chemical properties after coffee tree removal Rev. Bras. Ciênc. Solo Vieira,Sidney Rosa; Guedes Filho,Osvaldo; Chiba,Márcio Koiti; Cantarella,Heitor. Assessing the spatial variability of soil chemical properties has become an important aspect of soil management strategies with a view to higher crop yields with minimal environmental degradation. This study was carried out at the Centro Experimental of the Instituto Agronomico, in Campinas, São Paulo, Brazil. The aim was to characterize the spatial variability of chemical properties of a Rhodic Hapludox on a recently bulldozer-cleaned area after over 30 years of coffee cultivation. Soil samples were collected in a 20 x 20 m grid with 36 sampling points across a 1 ha area in the layers 0.0-0.2 and 0.2-0.4 m to measure the following chemical properties: pH, organic matter, K+, P, Ca2+, Mg2+, potential acidity, NH4-N, and NO3-N. Descriptive statistics were... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Soil fertility; Traditional management; Semivariogram. Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000500041 Sampling Design of Soil Physical Properties in a Conilon Coffee Field Rev. Bras. Ciênc. Solo Santos,Eduardo Oliveira de Jesus; Gontijo,Ivoney; Silva,Marcelo Barreto da; Partelli,Fábio Luiz. ABSTRACT Establishing the number of samples required to determine values of soil physical properties ultimately results in optimization of labor and allows better representation of such attributes. The objective of this study was to analyze the spatial variability of soil physical properties in a Conilon coffee field and propose a soil sampling method better attuned to conditions of the management system. The experiment was performed in a Conilon coffee field in Espírito Santo state, Brazil, under a 3.0 × 2.0 × 1.0 m (4,000 plants ha-1) double spacing design. An irregular grid, with dimensions of 107 × 95.7 m and 65 sampling points, was set up. Soil samples were collected from the 0.00-0.20 m depth from each sampling point. Data were analyzed under... Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffea canephora; Geostatistics; Soil sampling. Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100411 Spatial relationships between soil attributes and corn yield in no-tillage system Rev. Bras. Ciênc. Solo Rodrigues,Marcos Sales; Corá,José Eduardo; Fernandes,Carolina. Soil properties play an important role in spatial variability of crop yield. However, a low spatial correlation has generally been observed between maps of crop yield and of soil properties. The objectives of the present investigation were to assess the spatial pattern variability of soil properties and of corn yield at the same sampling intensity, and evaluate its cause-and-effect relationships. The experimental site was structured in a grid of 100 referenced points, spaced at 10 m intervals along four parallel 250 m long rows spaced 4.5 m apart. Thus, points formed a rectangle containing four columns and 25 rows. Therefore, each sampling cell encompassed an area of 45 m² and consisted of five 10 m long crop rows, in which the referenced points... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Precision agriculture; Soil sampling intensity; Spatial correlation; Zea mays. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000200029 Spatial-temporal variability of leaf chlorophyll and its relationship with cocoa yield AGRIAMBI Medauar,Caique C.; Galvão,Ícaro M.; Carvalho,Luis C. C.; Silva,Samuel de A.. ABSTRACT The objective of this study was to evaluate the spatial-temporal variability of leaf chlorophyll index and its relationship with cocoa yield. The experiment was carried out in an experimental area of cocoa production located in Ilhéus, Bahia State, Brazil. Leaf chlorophyll content was measured in September, October, January, February, March and April in the 2014/2015 season, at each sampling point of a regular grid by using a portable chlorophyll meter. Under the same conditions, yield was evaluated and the data were submitted to descriptive statistics and a linear correlation study. Geostatistical analysis was used to determine and quantify the spatial and temporal variability of leaf chlorophyll index and yield. Leaf chlorophyll index varied... Tipo: Info:eu-repo/semantics/article Palavras-chave: Theobroma cacao; Geostatistics; Thematic maps. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000300164 Spatial variability and changes in carbon stocks of a Regosols (Psamments) cultivated with sisal AGRIAMBI Sacramento,José A. A. S. do; Santos,Jorge A. G.; Loureiro,Diego C.; Costa,Oldair V.; Cova,Alide M. W.. ABSTRACT Information on spatial variability and soil carbon stocks after the conversion of Caatinga vegetation to different cropping systems is scarce. This study aimed to characterize the spatial variability and to evaluate the changes in carbon stocks and the emission of greenhouse gases after the conversion of Caatinga vegetation with different sisal cultivation systems. The study was carried out in three areas in the city of Valente, Bahia, two areas that had been cultivated for 20 years with sisal in either a traditional (TSC) or alternative (ASC) system, and the third area containing natural Caatinga vegetation. The cultivated soils were sampled at 40 soil sampling points with 15 × 10 m spacing at depths of 0-0.20 and 0.20-0.40 m. Total organic... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Alternative farming; Caatinga; Carbon emission factor. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018001100764 Spatial and multivariate analysis of soybean productivity and soil physical-chemical attributes AGRIAMBI Buss,Ricardo N.; Silva,Raimunda A.; Siqueira,Glécio M.; Leiva,Jairo O. R.; Oliveira,Osmann C. C.; França,Victor L.. ABSTRACT The objective of this study was to evaluate the spatial variability of soybean yield, carbon stock, and soil physical attributes using multivariate and geostatistical techniques. The attributes were determined in Oxisols samples with clayey and cohesive textures collected from the municipality of Mata Roma, Maranhão state, Brazil. In the study area, 70 sampling points were demarcated, and soybean yield and soil attributes were evaluated at soil depths of 0-0.20 and 0.20-0.40 m. Data were analysed using multivariate analyses (principal component analysis, PCA) and geostatistical tools. The mean soybean yield was 3,370 kg ha-1. The semivariogram of productivity, organic carbon (OC), and carbon stock (Cst) at the 0-0.20 m layer were adjusted to the... Tipo: Info:eu-repo/semantics/article Palavras-chave: Management zones; Geostatistics; Principal components. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000600446 Zoning of water requirement satisfaction index for common bean in Mato Grosso AGRIAMBI Fenner,William; Dallacort,Rivanildo; Dalchiavon,Flávio C.; Santi,Adalberto; Silva,Fabrício S. da; Barbieri,João D.. ABSTRACT The aim of this study was the agroclimatic zoning of common bean in the Mato Grosso state in the second harvest. Data from 38 meteorological stations in the state and in neighboring regions were used. The zoning was based on water requirement satisfaction index (WRSI) for the common bean crop, for the three levels of available water capacity of the soils of the state (30, 50 and 75 mm) in 12 sowing periods. After generating the indexes for the municipalities, the variograms of the data were fitted in order to enable interpolation of the data for the state. Data were entered into ArcGISTM 10.0 and the ordinary kriging interpolation method was used. After generating the maps, they were clipped to the Mato Grosso State and classified as the following... Tipo: Info:eu-repo/semantics/article Palavras-chave: Phaseolus vulgaris; Geotechnology; Geostatistics; Sowing dates. Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000700476 Spatial variability of enthalpy in rabbit house with and without ridge vent AGRIAMBI Ferraz,Patrícia F. P.; Ferraz,Gabriel A. e S.; Damasceno,Flavio A.; Moura,Raquel S. de; Silva,Maria A. J. G.; Rodrigues,Rodrigo de L.. ABSTRACT The profitability of a rabbit farming system must consider the rabbit’s breed, nutrition, management, sanitation and mainly the thermal environment that the animal will be exposed during the productive period. The aim of this study was to compare the internal thermal environment of two rabbit houses, one with ridge vent and the other without ridge vent. Geostatistical technique was used to evaluate the spatial variability of enthalpy. Data were collected at 48 points in each house during eight days at the end of summer season 2016. Measurements of dry-bulb temperature, relative humidity and wind speed were made for 1 min at three times a day at 7:00 a.m., 12:00 a.m. and 5:00 p.m. In addition, the enthalpy was calculated and a data analysis was... Tipo: Info:eu-repo/semantics/article Palavras-chave: Ambience; Welfare; Rabbit breeding; Geostatistics; Mapping. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000200126 Spatial variability of air temperature in a free-stall in the Northeastern semi-arid region of Brazil AGRIAMBI Gonçalves,Indira C. M.; Turco,Silvia H. N.; Ramos,Clóvis M. C.. ABSTRACT The knowledge on the spatial variability of climatic attributes and the building of Kriging maps can assist in the design and management of confined animal facilities, by allowing a spatial visualization that is helpful for the planning and control of information from the production environment. The study aimed to characterize the spatial variability of air temperature in a free-stall barn used for dairy cattle confinement located in Petrolina-PE, Brazil, in different seasons and at different times. The variable air temperature was recorded at 136 points distributed in the areas under the shed and the shade cloth for the study of spatial variability and the construction of maps by Kriging. Air temperature data was collected in the winter and in... Tipo: Info:eu-repo/semantics/article Palavras-chave: Dairy cattle; Thermal comfort; Geostatistics; Animal production systems; Precision animal production. Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000100067 Stochastic simulations of calcium contents in sugarcane area AGRIAMBI Pereira,Gener T.; Teixeira,Daniel D. B.; Souza,Zigomar M. de; Oliveira,Ismênia R. de; Marques,José. Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Spatial interpolation; Sequential Gaussian simulation; Simulated annealing. Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662015000800767 Sampling grid density and lime recommendation in an Oxisol AGRIAMBI Bottega,Eduardo L.; Queiroz,Daniel M. de; Pinto,Francisco A. C.; Oliveira Neto,Antonio M. de; Vilar,Cesar C.; Souza,Cristiano M. A. de. The objective of this study was to evaluate the influence of different sampling grids density in the lime requirements in an Oxisol. The experiment was conducted at a rural property located in Sidrolândia city, Mato Grosso do Sul state, in the Brazilian ‘Cerrado’. In the soil attributes mapping, regular sampling grid was used consisting of 99 points, spread over an area of 90 ha. Other two grids (51 and 27 points) were derived by deleting lines or lines and points from the original one. Based on the results of soil analysis, the lime requirement at each sample point was calculated. Using geostatistical techniques the spatial variability of lime requirement was studied and grid configuration for each sample was tested. By kriging, maps were made. By... Tipo: Info:eu-repo/semantics/article Palavras-chave: Precision agriculture; Geostatistics; Spatial variability; Soil acidity correction. Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662014001100008 Fuzzy modeling of the risk of cacao moniliasis occurrence in Bahia state, Brazil AGRIAMBI Almeida,Samira L. H. de; Silva,Samuel de A.; Lima,Julião S. de S.; Rosas,Jorge T. F.; Capelini,Vinicius A.. ABSTRACT This work aimed to determine potential areas for the establishment of cocoa moniliasis in Bahia state, Brazil, by means of fuzzy logic, based on historical datasets of temperature and air relative humidity, available for 519 measurement points distributed throughout the state of Bahia. The data were initially submitted to a descriptive statistical analysis. The spatial variability was determined through geostatistical analysis, followed by interpolation to map the spatial-temporal structure dependence of the phenomenon. Simulations of continuous pixel-to-pixel classification of variables were performed using fuzzy mapping to model the climatic risk of disease establishment. The exponential fuzzy model was applied to temperature data, while the... Tipo: Info:eu-repo/semantics/article Palavras-chave: Moniliophthora roreri; Theobroma cacao; Climate change; Geostatistics; Precision phytopathology. Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662020000400225 Spatial variability of enthalpy in broiler house during the heating phase AGRIAMBI Ferraz,Patrícia F. P.; Yanagi Junior,Tadayuki; Ferraz,Gabriel A. e S.; Schiassi,Leonardo; Campos,Alessandro T.. ABSTRACT The thermal environment inside a broiler house has a great influence on animal welfare and productivity during the production phase. Enthalpy is a thermodynamic property that has been proposed to evaluate the internal broiler house environment, for being an indicator of the amount of energy contained in a mixture of water vapor and dry air. Therefore, this study aimed to characterize the spatial variability of enthalpy in a broiler house during the heating phase using geostatistics. The experiment was conducted in the spring season, in a commercial broiler house with heating system consisting of two furnaces that heat the air indirectly, in the first 14 days of the birds' life. It was possible to characterize enthalpy variability using... Tipo: Info:eu-repo/semantics/article Palavras-chave: Poultry farming; Thermal comfort; Geostatistics; Kriging; Chicks.. Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000600570 Spatial variability of soil properties and cotton yield in the Brazilian Cerrado AGRIAMBI Motomiya,Anamari V. A; Molin,José P; Motomiya,Wagner R; Vieira,Sidney R. This research aimed at assessing the spatial variability and relationships between factors that affect cotton (Gossypium hirsutum L.) yield. Plant and soil data were collected by a 90 ha area divided in a regular grid of 100 m. In order to detect the variation at small scale, more intense samplings were made with spacing of 33 m, resulting in 5 "clusters" and totalizing 170 samples. Data were submitted to descriptive statistical analysis, geostatistic and interpolation through ordinary kriging. Variability expressed by the coefficient of variation was from low to moderate for all the variables except for retained bolls and soil P content. Geostatistical analysis indicated that most cotton yield factors presented spatial dependence and this should be... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Nutritional state; Spatial dependence. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662011001000002 Multifractal analysis of soil penetration resistance under sugarcane cultivation AGRIAMBI Leiva,Jairo O. R.; Silva,Raimunda A.; Buss,Ricardo N.; França,Victor L.; Souza,Anderson A.; Siqueira,Glécio M.. ABSTRACT Soil resistance to penetration (PR) is an indirect measure of the state of soil compaction. Thus, the objective of this study was to characterize PR in vertical profiles in an area cultivated with sugarcane using multifractal models for different relief units. The experiment was carried out in an Oxisol with a clay texture, with 6.85 ha in the municipality of Coelho Neto (Maranhão state, Brazil), where 60 sampling points were demarcated. The area was divided into four relief units (Type A > 74 m, Type B from 71 to 74 m, Type C from 68 to 71 m and Type D from 65 to 68 m). The PR was measured at the 60 sampling points using an impact penetrometer, and the PR determined in the 0-0.60 m depth layer every 0.01 m. The multifractal analysis was... Tipo: Info:eu-repo/semantics/article Palavras-chave: Fractal geometry; Fractal dimension; Singularity spectrum; Geostatistics; Soil management. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000700538 Spatial variability of soil attributes in an experimental basin in the semi-arid region of Pernambuco, Brazil AGRIAMBI Araújo,Diego C. dos S.; Montenegro,Suzana M. G. L.; Montenegro,Abelardo A. de A.; Silva Junior,Valdemir de P. e; Santos,Sylvana M. dos. ABSTRACT This study aimed to evaluate the spatial patterns of physical and chemical properties of a soil in an experimental basin with an area of 149 km2, located in the municipality of Pesqueira, in the semi-arid region of Pernambuco state (Brazil). Samples were taken in the layers of 0-0.10 and 0.10-0.20 m, at 35 monitoring points distributed in an irregular grid, encompassing the three soil classes present in the basin and commonly found in the semi-arid region. For the attributes of soil texture, organic carbon and bulk density in the layer of 0.10-0.20 m, spatial dependence from medium to strong was detected, ranging from 0.03 to 49.98%. Bulk density in the layer 0-0.10 m, as well as the electrical conductivity, in both layers, showed pure nugget... Tipo: Info:eu-repo/semantics/article Palavras-chave: Kriging; Geostatistics; Caatinga. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000100038 Spatial variability of soil attributes and sugarcane yield in relation to topographic location AGRIAMBI Souza,Zigomar M. de; Cerri,Domingos G. P.; Magalhães,Paulo S. G.; Siqueira,Diego S.. Soils submitted to the same management system in places with little variation of landscape, manifest differentiated spatial variability of their attributes and crop yield. The aim of this work was to investigate the correlation between spatial variability of the soil attributes and sugarcane yield as a result of soil topography. To achieve this objective, a test area of 42 ha located at the São João Sugar Mill, in Araras, in the State of São Paulo, Brazil, was selected. Sugarcane yield was measured with a yield monitor fitted in a sugarcane harvester and GPS signal. A total of 170 soil samples were taken at regular 50 m grid, at a depth of 0 - 0.2 m. The area under study was divided into two sites based on topography. The following soil attributes were... Tipo: Info:eu-repo/semantics/article Palavras-chave: Saccharum sp; Geostatistics; Semivariogram; Curvature; Precision agriculture. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010001200001 Variability and spatial correlation of soil micronutrients and organic matter with macadamia nut production AGRIAMBI Paris,Jaqueline O.; Gontijo,Ivoney; Partelli,Fábio L.; Facco,Alexandro G.. ABSTRACT Soil fertility is the key to agricultural production. The spatial correlation and location of nutrients may significantly affect the yields. The objective of this work was to evaluate the variability and spatial correlation of iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), and organic matter (OM) with macadamia nut yield. The study was conducted in an Oxisol cultivated for 20 years with macadamia nut in São Mateus, state of Espírito Santo, Brazil. A 100 point grid was used comprising an area of 144 × 140 m with a minimum distance between points of 5 m, in which a single composite soil sample was collected from 0-0.20 m layer for chemical analysis of Fe, Cu, Mn, Zn and OM. Nuts under the canopy’s projection were harvested from February to June,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Macadamia integrifolia; Spatial variability; Geostatistics; Plant nutrition. Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662020000100031 Registros recuperados: 159 Primeira ... 1 2 3 4 5 6 7 8 ... Última

Empresa Brasileira de Pesquisa Agropecuária - Embrapa Todos os direitos reservados, conforme Lei n° 9.610 Política de Privacidade Área restrita		Embrapa Parque Estação Biológica - PqEB s/n° Brasília, DF - Brasil - CEP 70770-901 Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco