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A Classification for a Geostatistical Index of Spatial Dependence Rev. Bras. Ciênc. Solo
Seidel,Enio Júnior; Oliveira,Marcelo Silva de.
ABSTRACT: In geostatistical studies, spatial dependence can generally be described by means of the semivariogram or, in complementary form, with a single index followed by its categorization to classify the degree of such dependence. The objective of this study was to construct a categorization for the spatial dependence index (SDI) proposed by Seidel and Oliveira (2014) in order to classify spatial variability in terms of weak, moderate, and strong dependence. Theoretical values were constructed from different degrees of spatial dependence, which served as a basis for calculation of the SDI. In view of the form of distribution and SDI descriptive measures, we developed a categorization for posterior classification of spatial dependence, specific to each...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Spatial dependence; Spatial variability; Semivariogram; Summary measures.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100313
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Análise de componentes principais de atributos químicos e físicos do solo limitantes à produtividade de grãos. Repositório Alice
SANTI, A. L.; AMADO, T. J. C.; CHERUBIN, M. R.; MARTIN, T. N.; PIRES, J. L. F.; DELLA FLORA, L. P.; BASSO, C. J..
2012
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Agricultura de precisão; Análise multivariada; Variabilidade espacial; Variabilidade temporal; Zonas de manejo; Precision agriculture; Multivariate analysis; Spatial variability; Temporal variability; Management zones.
Ano: 2012 URL: http://www.alice.cnptia.embrapa.br/handle/doc/945807
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Análise de interpoladores na geração de mapas de precipitação para o Estado de Mato Grosso. Repositório Alice
TIEPPO, R. C.; NUNES, C. C. P.; DALLACORT, R.; FIETZ, C. R.; COMUNELLO, E.; CREMON, C..
2010
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Cerrado; Rede pluviométrica; Variabilidade espacial; Brazilian Savanna; Network rainfall; Spatial variability.
Ano: 2010 URL: http://www.alice.cnptia.embrapa.br/handle/doc/870188
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Analysis of the spatial variability of crop yield and soil properties in small agricultural plots Bragantia
Vieira,Sidney Rosa; Paz Gonzalez,Antonio.
The objective of this study was to assess spatial variability of soil properties and crop yield under no tillage as a function of time, in two soil/climate conditions in São Paulo State, Brazil. The two sites measured approximately one hectare each and were cultivated with crop sequences which included corn, soybean, cotton, oats, black oats, wheat, rye, rice and green manure. Soil fertility, soil physical properties and crop yield were measured in a 10-m grid. The soils were a Dusky Red Latossol (Oxisol) and a Red Yellow Latossol (Ultisol). Soil sampling was performed in each field every two years after harvesting of the summer crop. Crop yield was measured at the end of each crop cycle, in 2 x 2.5 m sub plots. Data were analysed using semivariogram...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial variability; Kriging; Yield map; Semivariogram.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052003000100016
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Aplicação da geoestatística na análise da fertilidade do solo em propriedade familiar do Circuito das Frutas do Estado de São Paulo. Infoteca-e
GREGO, C. R.; PAIM, F. A. de P.; RODRIGUES, C. A. G.; CRISCUOLO, C.; GARCON, E. A. M.; MANJOLIN, R. C.; ALVAREZ, I. A.; ALBUQUERQUE, T. C. S. de.
Este trabalho tem como objetivo o uso da análise geoestatística no mapeamento da fertilidade do solo de seis propriedades familiares do Circuito das Frutas, localizadas nos municípios de Itatiba, Atibaia, Jundiaí, Valinhos, Indaiatuba, Jarinú, no estado de São Paulo.
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) Palavras-chave: Geoestatística; Variabilidade espacial; Krigagem ordinária; Culturas frutíferas; Spatial variability; Ordinary kriging; Fruticultura; Fertilidade do Solo; Geostatistics; Fruit crops.
Ano: 2018 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1102129
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Assessing degradation of soils cultivated to irrigated corn. Repositório Alice
COELHO, A. M.; DORAN, J. W.; SCHEPERS. J. S..
2007
Tipo: Resumo em anais de congresso (ALICE) Palavras-chave: Soil degradation; Spatial variability; Soil quality.
Ano: 2007 URL: http://www.alice.cnptia.embrapa.br/handle/doc/490762
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Assessing degradation of soils cultivated to irrigated corn. Repositório Alice
COELHO, A. M.; DORAN, J. W.; SCHEPERS. J. S..
2007
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Soil degradation; Spatial variability; Soil quality.
Ano: 2007 URL: http://www.alice.cnptia.embrapa.br/handle/doc/490731
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ASSESSING SPATIAL BREAK-EVEN VARIABILITY IN FIELDS WITH TWO OR MORE MANAGEMENT ZONES AgEcon
English, Burton C.; Mahajanashetti, S.B.; Roberts, Roland K..
Farmers are interested in knowing whether applying inputs at variable rates across a field is economically viable. The answer depends on the crop, the input, their prices, the cost of variable rate technology (VRT) versus uninform rate technology (URT), and the spatial and yield response variability within each field. Methods were investigated for determining the range of spatial variability over which the return to VRT covers its additional cost compared with URT in fields with multiple management zones. Models developed in this article, or variants thereof, could be used to help farmers make the VRT adoption decision.
Tipo: Journal Article Palavras-chave: Management zones; Nitrogen; Precision farming; Site-specific management; Spatial break-even variability proportions; Spatial variability; Variable rate technology; Yield response variability; Farm Management.
Ano: 2001 URL: http://purl.umn.edu/15450
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BED TEMPERATURE IN COMPOST BARNS TURNED WITH ROTARY HOE AND OFFSET DISC HARROW REA
Mota,Vania C.; Andrade,Ednilton T. de; Leite,Daniel F..
ABSTRACT The success of confinement for dairy cattle in the compost barn model depends mainly on the management of the bed and consists of its turning. This paper characterises the spatial variability of the bed temperature in the compost barn confinement model, as well as verifying whether there was an effect on efficiency from turning the bed with different agricultural implements. The experiment was conducted during the summer and winter of 2016, with 8 days of collection in each period. Data were analysed with descriptive statistics methods and geostatistical modelling with semivariograms and kriging maps. The results of the t-test at a5% significance level indicated that, after turning the bed with the plough or rotary hoe, the temperature values were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Aeration/oxygenation of the bed; Dairy cattle; Confinement; Agricultural implements; Spatial variability.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000300280
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Can an increase in nitrogen rate mitigate damages caused by uneven spatial distribution of maize plants at the sowing row? Agronomy
Kolling, Daniel Fernando; Sangoi, Luís; Leolato, Lucieli Santini; Panison, Fernando; Coelho, Antonio Eduardo; Kuneski, Hugo François.
An uneven distribution of maize plants at the sowing row can decrease grain yield. This work was carried out to evaluate the effect of an increasing nitrogen rate on maize agronomic performance under different variation coefficients of plant spatial distributions at the sowing row. The experiment was conducted in Lages, Santa Catarina State, South Brazil. Three variation coefficients (VC) of plant spatial distribution (0, 50, and 100%) were tested. At the 0 level, seeds were evenly distributed 17 cm from each other. In the other treatments with uneven spatial distributions, the distances between two neighbouring seeds ranged from 2 to 54 cm. Four nitrogen side-dress rates (0, 125, 250, and 375 kgN ha-1) were evaluated. The increase in VC of plant spatial...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Zea mays; Spatial variability; Nitrogen side-dress; Grain yield..
Ano: 2019 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/39874
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Can an increase in nitrogen rate mitigate damages caused by uneven spatial distribution of maize plants at the sowing row? Agronomy
Kolling, Daniel Fernando; Sangoi, Luís; Leolato, Lucieli Santini; Panison, Fernando; Coelho, Antonio Eduardo; Kuneski, Hugo François.
An uneven distribution of maize plants at the sowing row can decrease grain yield. This work was carried out to evaluate the effect of an increasing nitrogen rate on maize agronomic performance under different variation coefficients of plant spatial distributions at the sowing row. The experiment was conducted in Lages, Santa Catarina State, South Brazil. Three variation coefficients (VC) of plant spatial distribution (0, 50, and 100%) were tested. At the 0 level, seeds were evenly distributed 17 cm from each other. In the other treatments with uneven spatial distributions, the distances between two neighbouring seeds ranged from 2 to 54 cm. Four nitrogen side-dress rates (0, 125, 250, and 375 kgN ha-1) were evaluated. The increase in VC of plant spatial...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Zea mays; Spatial variability; Nitrogen side-dress; Grain yield..
Ano: 2019 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/39874
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Caracterização espacial de indices de vegetação índice relativo de clorofila em áreas de produção cafés especiais no sul de Minas Gerais. Repositório Alice
RODRIGUES, G. C.; GREGO, C. R.; LUCHIARI JUNIOR, A.; SPERANZA, E. A..
RESUMO: A região sul do estado de Minas Gerais é grande produtora de café, principalmente daquele classificado como especial. Aspectos ambientais, entre outros fatores, interferem consideravelmente na produção desse tipo de café, envolvendo fatores como altitude e face de exposição do plantio ao sol. Este trabalho tem como objetivo avaliar a variabilidade espacial em áreas representativas de produção de café arábica (Coffea arabica) classificados como especiais do sul de Minas Gerais quanto aos índices vegetativos e de clorofila para identificar a existência de variabilidade espacial para aplicação da Agricultura de Precisão. Como resultado observou-se variabilidade espacial no NDVI, NDRE e IRC em todos os campos avaliados e trabalhos estão em andamento...
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Geoestatística; Variabilidade espacial; Café arábica; Índice de vegetação; Índice relativo de clorofila; Índice de Vegetação da Diferença Normalizada pelo Red-Edge; Spatial variability; Agricultura de Precisão; Café; Coffea Arábica; Precision agriculture; Geostatistics; Vegetation index.
Ano: 2019 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1114194
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Characterization and delimitation of the terroir coffee in plantations in the municipal district of Araponga, Minas Gerais, Brazil Rev. Ciênc. Agron.
Silva,Samuel de Assis; Queiroz,Daniel Marçal de; Pinto,Francisco de Assis de Carvalho; Santos,Nerilson Terra.
Differentiating coffees through the notion of terroirs allows us to determine potential areas for specialty coffee production and to characterize the type of coffee in these areas, exploring their potential. The objective of this work was to study spatial variability quality and to characterize and delimit terroirs in coffee crop production in Araponga municipality, Minas Gerais State, Brazil, using sensorial evaluation. The data were collected from four crops, from altitudes ranging from 770 to 1270 m, with the extract increasing from low to high. In each plot of crops, samples of cherry fruits were collected, dried, benefited, subjected to sensorial analysis and given grades ranging from 0 to 100 points for the global drink quality and relative...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geographical origin; Sensorial quality; Spatial variability.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000100003
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Characterization of noise emitted by a power tiller through geostatistics AGRIAMBI
Gonçalves,Luana M.; Ferraz,Gabriel A. e S.; Oliveira,Marcelo S. de; Barbosa,Brenon D. S.; Silva,Carlos J. da; Ferraz,Patrícia F. P..
ABSTRACT Noise is one of the harmful and stressful physical agents present in the workplace. Research performed with geostatistics to adjust the semivariogram of tractor noise were performed using the Gaussian and spherical model. In this way, the aim was to map the spatial variability of the noise emitted by a power tiller through the sine wave model, besides testing other fitting methods, in order to identify health zones for the workers. The experiment was performed with an agricultural power tiller (10.3 kW) placed in a working regime (1500 rpm), coupled to a brushcutter, and a digital sound level meter to collect noises in points distributed along a regular grid sampling of 2.0 × 2.0 m around the tractor. The spatial dependence of noise was analyzed...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Acoustic comfort; Agricultural mechanization; Spatial variability; Ergonomics; Sine wave model.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000300223
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Characterization of potential CO2 emissions in agricultural areas using magnetic susceptibility Scientia Agricola
Leal,Fábio Tiraboschi; França,Ana Beatriz Coelho; Siqueira,Diego Silva; Teixeira,Daniel De Bortoli; Marques Júnior,José; Scala Júnior,Newton La.
ABSTRACTSoil CO2 emissions (fCO2) in agricultural areas have been widely studied in global climate change research, but its characterization and quantification are restricted to small areas. Because spatial and time variability affect emissions, tools need to be developed to predict fCO2 for large areas. This study aimed to investigate soil magnetic susceptibility (MS) and its correlation with fCO2 in an agricultural environment. The experiment was carried out on a Typic Eutrudox located in Guariba-SP, Brazil. Results showed that there was negative spatial correlation between fCO2 and the magnetic susceptibility of Air Dried Soil (MSADS) up to 34.3 m distant. However, the fCO2 had no significant correlation with MSADS, magnetic susceptibility of sand...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Magnetism; Soil respiration; Spatial variability; Geostatistics.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000600535
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Comparison of neutron moisture gauges with nonnuclear methods to measure field soil water status Scientia Agricola
Kirda,C.; Reichardt,K..
The neutron moisture gauge is compared with the gravimetric-core soil sampling technique, tensiometers and resistance blocks in relation to stability, Held variability, spatial dependence and number of samples needed at a given level of significance. The variance of field water content measurements with neutron moisture gauges is lower than that of the gravimetric sampling, which therefore requires 2 to 6 times as many samples as the number of measuring sites of the gauges to attain the same level of significance. The space dependence of the measurements made with the subsurface gauge varied depending on the average field soil water content. No space dependence was evident when the water content was lower than 0.2 cm³.cm-3 (50% saturation). Measurements...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Neutron gauges; Tensiometers; Resistance blocks; Spatial variability; Soil water.
Ano: 1992 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161992000400015
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Computational system for geostatistical analysis. Repositório Alice
VENDRUSCULO, L. G.; MAGALHÃES, P. S. G.; VIEIRA, S. R.; CARVALHO, J. R. P. de.
ABSTRACT: Geostatistics identifies the spatial structure of variables representing several phenomena and its use is becoming more intense in agricultural activities. This paper describes a computer program, based on Windows Interfaces (Borland Delphi), which performs spatial analyses of datasets through geostatistic tools: Classical statistical calculations, average, cross- and directional semivariograms, simple kriging estimates and jackknifing calculations. A published dataset of soil Carbon and Nitrogen was used to validate the system. The system was useful for the geostatistical analysis process, for the manipulation of the computational routines in a MS-DOS environment. The Windows development approach allowed the user to model the semivariogram...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Variabilidade espacial; Semivariograma; Geoestatística; Spatial variability; Semivariogram; Tecnologia da informação; Information technology; Computer software; Geostatistics.
Ano: 2004 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/9084
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Computational system for geostatistical analysis Scientia Agricola
Vendrusculo,Laurimar Gonçalves; Magalhães,Paulo Sérgio Graziano; Vieira,Sidney Rosa; Carvalho,José Ruy Porto de.
Geostatistics identifies the spatial structure of variables representing several phenomena and its use is becoming more intense in agricultural activities. This paper describes a computer program, based on Windows Interfaces (Borland Delphi), which performs spatial analyses of datasets through geostatistic tools: Classical statistical calculations, average, cross- and directional semivariograms, simple kriging estimates and jackknifing calculations. A published dataset of soil Carbon and Nitrogen was used to validate the system. The system was useful for the geostatistical analysis process, for the manipulation of the computational routines in a MS-DOS environment. The Windows development approach allowed the user to model the semivariogram graphically...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial variability; Semivariogram; Software.
Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000100017
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Delineation of irrigation management zones in a Quartzipsamment of the brazilian Semiarid region. Repositório Alice
OLDONI, H.; BASSOI, L. H..
The objective of this work was to delineate irrigation management zones using geostatistics and multivariate analysis in different combinations of physical and hydraulic soil properties, as well as to determine the optimal number of management zones in order to avoid overlaping. A field experiment was carried out in a Quartzipsamment, for two years, in an irrigated orchard of table grape, in the Senador Nilo Coelho Irrigation Scheme, in the municipality of Petrolina, in the state of Pernanbuco, Brazil. Soil samples were collected for the determination of soil physico-hydraulic properties. A portable meter was used to measure soil apparent electrical conductivity. Spatial distribution maps were generated using ordinary kriging. Management zones for five...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Fuzzy c-means; Irrigation planning; Soil apparent electrical conductivity; Spatial variability; Geoestatística; Planejamento da irrigação; Condutividade elétrica aparente do solo; Variabilidade espacial; Semiárido; Agricultura de precisão; Solo; Geostatistics; Precision agriculture.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1061546
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Delineation of irrigation management zones in a Quartzipsamment of the Brazilian semiarid region PAB
Oldoni,Henrique; Bassoi,Luís Henrique.
Abstract The objective of this work was to delineate irrigation management zones using geostatistics and multivariate analysis in different combinations of physical and hydraulic soil properties, as well as to determine the optimal number of management zones in order to avoid overlaping. A field experiment was carried out in a Quartzipsamment, for two years, in an irrigated orchard of table grape, in the Senador Nilo Coelho Irrigation Scheme, in the municipality of Petrolina, in the state of Pernanbuco, Brazil. Soil samples were collected for the determination of soil physico-hydraulic properties. A portable meter was used to measure soil apparent electrical conductivity. Spatial distribution maps were generated using ordinary kriging. Management zones for...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fuzzy c-means; Geostatistics; Irrigation planning; Precision agriculture; Soil apparent electrical conductivity; Spatial variability.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901283
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