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Terrain forms and spatial variability of soil properties in an area cultivatedwith citrus REA
Leão,Marisol G. A. de; Marques Júnior,José; Souza,Zigomar M. de; Siqueira,Diego S.; Pereira,Gener T..
The technique of precision agriculture and soil-landscape allows delimiting areas for localized management, allowing a localized application of agricultural inputs and thereby may contribute to preservation of natural resources. Therefore, the objective of this work was to characterize the spatial variability of chemical properties and clay content in the context of soil-landscape relationship in a Latosol (Oxisol) under cultivation of citrus. Soil samples were collected at a depth of 0.0-0.2 m in an area of 83.5 ha planted with citrus, as a 50-m intervals grid, with 129 points in concave terrain and 206 points in flat terrain, totaling 335 points. Values for the variables that express the chemical characteristics and clay content of soil properties were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Management zone; Oxisol; Orange.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162011000400003
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Magnetic susceptibility in the prediction of soil attributes in two sugarcane harvesting management systems REA
Peluco,Rafael G.; Marques Júnior,José; Siqueira,Diego S.; Cortez,Lucas A.; Pereira,Gener T..
This study aimed to investigate the potential use of magnetic susceptibility (MS) as pedotransfer function to predict soil attributes under two sugarcane harvesting management systems. For each area of 1 ha (one with green sugarcane mechanized harvesting and other one with burnt sugarcane manual harvesting), 126 soil samples were collected and subjected to laboratory analysis to determine soil physical, chemical and mineralogical attributes and for measuring of MS. Data were submitted to descriptive statistics by calculating the mean and coefficient of variation. In order to compare the means in the different harvesting management systems it was carried out the Tukey test at a significance level of 5%. In order to investigate the correlation of the MS with...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pedotransfer; Indirect quantification; Oxisol.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000600006
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Outlining precision boundaries among areas with different variability standards using magnetic susceptibility and geomorphic surfaces REA
Matias,Sammy S. R.; Marques Júnior,José; Siqueira,Diego S.; Pereira,Gener T..
There is an increasing demand for detailed maps that represent in a simplified way the knowledge of the variability of a particular area or region maps. The objective was to outline precision boundaries among areas with different accuracy variability standards using magnetic susceptibility and geomorphic surfaces. The study was conducted in an area of 110 ha, which identified three compartment landscapes based on the geomorphic surfaces model. To determinate pH, organic matter, phosphorus, potassium and magnesium, the total sand and clay, 514 soil samples were collected at depths of 0-0.20 m and 0.60-0.80 m. The sum of base, cationic exchange capacity and base saturation were calculated and the magnetic susceptibility was evaluated in the laboratory using...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Detailed mapping; Pedometrics; Accuracy boundaries.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000400009
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SAMPLING DENSITY FOR CHARACTERIZING THE PHYSICAL QUALITY OF A SOIL UNDER COFFEE CULTIVATION IN SOUTHWESTERN MINAS GERAIS REA
Silvero,Nélida E. Q.; Marques Júnior,José; Siqueira,Diego S.; Gomes,Romário P.; Costa,Milene M. R..
ABSTRACT The elaboration of maps to characterize the spatial variability of soil attributes assists in the strategic planning and decision making of agricultural managers. Precision and accuracy of maps are related to the ideal sampling density to characterize the variability pattern. This study was conducted with the aim of identifying the sampling density to represent the variability of soil physical quality using attributes with different magnitudes of variation in an area cultivated with coffee. Three approaches were used to find the most adequate sampling density (geostatistical analysis, percentage of error associated with the sampling density, and coefficient of variation). A total of 145 soil samples were collected at a depth of 0-0.20 m at the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Precision agriculture; Coffea arabica; Sampling error; Geostatistics.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000500718
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MODELING OF PHOSPHORUS LOSSES BY WATER EROSION REA
Farias,Vera L. da S.; Martins Filho,Marcílio V.; Paula,Daniela T. de; Siqueira,Diego S..
ABSTRACT Phosphorus losses in runoff water and eroded sediment may increase the risk of eutrophication. Erosion prediction models can be used to assess and quantify nutrient losses and transport in different soil management scenarios. This study aimed to assess the performance of models to estimate the losses of available phosphorus in eroded sediments and assess their spatial variability pattern. The experiment was installed on a eutrophic Red Ultisol located in Tabapuã, northwestern São Paulo State, São Domingos Stream Watershed. Aiming at estimating and validating the models, measurements were made from 2007 to 2015 at 17 observation points (slopes), determining soil phosphorus content (Psoil), eroded sediments (Psed), and enrichment rate (ERsed). The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: WEPP model; Enrichment rate; Spatial variability.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000100149
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Erosion factors and magnetic susceptibility in differet compartments of a slope in Gilbués-PI, Brazil REA
Santos,Hélio L.; Marques Júnior,José; Matias,Sammy S. R.; Siqueira,Diego S.; Martins Filho,Marcílio V..
The erosion is the degradation of soil with effects on crop productivity and pollution of the environment. To understand the spatial variability of this phenomenon, geostatistical techniques and concepts of soil-landscape can be used to identify landscape compartments with different potential of erosion. The aim of this study was to understand the factors of erosion in landscape compartments and the relations with the magnetic susceptibility (MS) of the soils in a slope in Gilbués, state of Piauí (PI), Brazil. Sampling meshes were set in compartments I and II with 121 points and in compartment III with 99 points spaced every 10 meters. There was significant difference to erodibility (K) and risk of erosion (RE); the spatial variability of MS was lower than...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Indirect quantification; Geostatistics; Conservation planning; Compartments; Topography; Relief; Landscape.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000100008
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CLAY AND PHOSPHORUS LOSSES BY EROSION IN OXISOL WITH SUGARCANE RESIDUES REA
Paula,Daniela T. De; Martins Filho,Marcílio V.; Farias,Vera L. DA S.; Siqueira,Diego S..
ABSTRACT Considering the importance of nutrients in the soil for the plants development and the soil quality conservation and the quantification relevance of them for proper soil management, the aims of this research were: (i) to quantify the clay loss, adsorbed and soluble P from interrill erosion influenced by the presence of sugarcane residues on the ground surface; (ii) to determine the minimum percentage of residues to be maintained on the soil surface to not enrich the eroded sediment by clay and soluble P (Psed) and adsorbed (Pads). The experimental area is located in Guariba - SP, with soil classified as Red Dystrophic Oxisol. The experiment was designed based on results of previous experiments with residue analysis of variance for 40 plots. These...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Interrill erosion; Simulated rainfall; Vegetation cover.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000601063
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Mapeamento das formas do relevo para estimativa de custos de fertilização em cana-de-açúcar REA
Sanchez,Rodrigo B.; Marques Júnior,José; Pereira,Gener T.; Baracat Neto,Jorge; Siqueira,Diego S.; Souza,Zigomar M. de.
A modelagem matemática associada ao conhecimento da variabilidade dos atributos do solo e mapeamento das formas do relevo pode auxiliar no manejo da fertilidade do solo em usinas sucroalcooleiras. O presente trabalho teve como objetivo avaliar o uso da geoestatística e da modelagem matemática na estimativa de custos de fertilização, em diferentes formas do relevo. Em uma área de 200 ha, foram identificadas duas formas de relevo, uma côncava e outra convexa, sendo os solos coletados nos pontos de cruzamento de uma malha, com intervalos regulares de 50 m, perfazendo um total de 623 pontos. As amostras foram submetidas a análises químicas, e, posteriormente, os dados foram avaliados por meio da estatística descritiva, geoestatística e modelagem matemática. Os...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Zonas de manejo específico; Taxa variada; Agricultura de precisão.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000200008
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Classificação numérica e modelo digital de elevação na caracterização espacial de atributos dos solos AGRIAMBI
Silva Júnior,João F. da; Siqueira,Diego S.; Marques Júnior,José; Pereira,Gener T..
Uma das necessidades da agricultura moderna é a predição da variabilidade espacial dos atributos dos solos em escalas mais detalhadas, visando o gerenciamento sustentável e a otimização das práticas de manejo dos solos. Associada ao conhecimento da variabilidade dos atributos do solo e ao mapeamento das formas do relevo, a modelagem matemática tem auxiliado no planejamento agrícola. Objetivou-se então, no presente trabalho, caracterizar a variabilidade espacial de atributos físicos e químicos de Latossolo e Argissolo utilizando-se a classificação numérica e o modelo digital de elevação em duas áreas, identificadas por duas pedoformas distintas: pela convexa, para o Latossolo (158 ha) e por meio da linear, para o Argissolo (172 ha). Foram retiradas 53...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Análise multivariada; Agricultura precisão; Mapeamento híbrido; Relação solo-paisagem.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662012000400012
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O relevo na interpretação da variabilidade espacial dos teores de nutrientes em folha de citros AGRIAMBI
Leão,Marisol G. A. de; Marques Júnior,José; Souza,Zigomar M. de; Siqueira,Diego S.; Pereira,Gener T..
A diagnose foliar é um critério para avaliação do estado nutricional das culturas agrícolas, que auxilia na compreensão da fertilidade do solo e na aplicação racional de adubos, levando em conta aspectos econômicos e ambientais. O trabalho teve como objetivo utilizar as formas do relevo como regra para auxiliar na interpretação da variabilidade espacial dos teores de nutrientes da folha de citros. Coletas de folhas foram realizadas em intervalos regulares de 50 m, totalizando 332 pontos de amostragem. Os dados foram analisados pela estatística descritiva, geoestatística e indução da árvore de decisão. Com o auxílio do modelo digital de elevação (MDE) e do perfil planialtimétrico, a área foi dividida em diferentes formas do relevo e segmentos de vertente....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Laranja; Krigagem; Mineração de dados; Relação solo-paisagem.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010001100004
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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
Registros recuperados: 11
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