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	Provedor de dados PAB (1) Autor BORDINGNON,JOSÉ RENATO (1) CARRÃO-PANIZZI,MERCEDES CONCÓRDIA (1) Palavra-chave Aglycones (1) Environmental effect (1) Glycine max (1) Soybean flavor (1) Tipo do documento Info:eu-repo/semantics/article (1) Ano 2000 (1) País Brazil (1) Idioma Inglês (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 31 Primeira ... 1 2 ... Última Fractal dimension and geostatistical parameters for soil microrelief as a function of cumulative precipitation Scientia Agricola Vázquez,Eva Vidal; Vieira,Sidney Rosa; De Maria,Isabella Clerici; González,Antonio Paz. Surface roughness isinfluenced by type and intensity of soil tillage among other factors, and it changes considerably with rain. In microrelief studies the advantages of using indices such as the fractal dimension, D, and the crossover length, l, is that they allow the partition of the roughness characteristics into properties that depend purely on the scale and on a scale free component, respectively. On the other hand, some geostatistical parameters may provide different ways to understand soil surface variability not addressed with fractal parameters. Changes in fractal dimension and semivariogram parameters for surface roughness evolution were evaluated as a function of cumulative rainfall on Oxisol samples over six tillage treatments, namely, disc... Tipo: Info:eu-repo/semantics/article Palavras-chave: Oxisol; Tillage; Soil surface roughness; Semivariogram; Crossover length. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000100011 Spatial dependency and correlation of properties of soil cultivated with oil palm, Elaeis guineensis, in agroforestry systems in the eastern Brazilian Amazon Acta Amazonica SILVA,Camila Santos da; MENDONÇA,Bruno Araujo Furtado de; PEREIRA,Marcos Gervasio; ARAÚJO,Emanuel José Gomes de; CASTELLANI,Débora Christina. ABSTRACT Geostatistics is a tool that can be used to produce maps with the distribution of nutrients essential for the development of plants. Therefore, the present study aimed to analyze the spatial variation in chemical attributes of soils under oil palm cultivation in agroforestry systems in the eastern Brazilian Amazon, and their spatial dependence pattern. Sixty spatially standardized and georeferenced soil samples were collected at each of three sampling sites (DU1, DU2, and DU3) at 0-20 cm depth. Evaluated soil chemical attributes were pH, Al3+, H+Al, K+, Ca2+, Mg2+, cation exchange capacity (CEC), P, and organic matter (OM). The spatial dependence of these variables was evaluated with a semivariogram analysis, adjusting three theoretical models... Tipo: Info:eu-repo/semantics/article Palavras-chave: Cokriging; Ordinary kriging; Semivariogram; Soil properties. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672018000400280 Spatial variability of soil potassium in sugarcane areas subjected to the application of vinasse Anais da ABC (AABC) CARVALHO,LAÉRCIO A. DE; MEURER,ISMAEL; JUNIOR,CARLOS A. DA SILVA; SANTOS,CRISTIANE F.B.; LIBARDI,PAULO L.. When deposited on land the vinasse can promote improvement in fertility, however, often fertilizer application occurs in areas considered homogeneous, without taking into account the variability of the soil. The objective of this study was to evaluate the effect of vinasse application on potassium content in two classes of soils cultivated with sugarcane, and characterize the spatial variability of soil using geostatistical techniques. In the 2010 and 2011 crop year, soil samples were collected from an experimental grid at 0-0.2 and 0.2-0.4 m depth in three soils cultivated with sugarcane, totaling 90 samplings in each grid, for the determination of pH, calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), aluminum (Al) and potential acidity (H +... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Saccharum officinarum; Semivariogram; Soil fertility. Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401999 Spatial and temporal variability of Eh and pH over a rice field as related to lime addition Bragantia Morales,Luis Alberto; Paz-Ferreiro,Jorge; Vieira,Sidney Rosa; Vázquez,Eva Vidal. The aim of this study was to describe the effect of lime additions on the spatial variability of pH and Eh in a typic Plintacualf cultivated with rice, in Corrientes, Argentina. The 5.1 ha field was divided in three sub plots at which dolomitic lime additions were made at the rates zero, 625 kg ha-1 and 1250 kg ha-1. The soil was sampled at three stages: before sowing thus in aerobic conditions, and then two more times in anaerobiosis. Ninety-six samples per sub plot were taken on each of the three sampling stages on a grid of 11.9 x 20 m. Soil pH and Eh were measured by routine methods. The pH values increased, whereas Eh values decreased, following flooding. The coefficients of variation for pH was rather low during all the three studied periods.... Tipo: Info:eu-repo/semantics/article Palavras-chave: Semivariogram; Flooded field; Liming; Kriging. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500008 Spatial variability studies in São Paulo, Brazil along the last twenty five years Bragantia Vieira,Sidney Rosa; Dechen,Sonia Carmela Falci. Soil properties vary in space due to many causes. For this reason it is wise to know the magnitude and behaviour of the variability for adequate data analysis and decision making. Our work on spatial variability of soil properties in São Paulo, Brazil began in 1982 with a very simple soil sampling in a small field. Much progress has been made since then on sampling designs, field equipment and methods, and mostly on computation equipment and softwares. This paper reports the results corresponding to some aspects of this progress, as far as the field, analysis and computation work are concerned. The objective of this study was to illustrate the use of geostatistics in data analysis for three sampling conditions on long term no-tillage system. The analysis... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Semivariogram; Temporal variation; Grain crop yield. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500007 Analyzing spatial and temporal variability of soil water content Bragantia Vieira,Sidney Rose; Grego,Célia Regina; Topp,George Clarke. During the last two decades geoestatistical methods have been intensively used for in-depth descriptions of spatial variability. The objective of this study was to assess the spatial and temporal variability of soil water content. The measurements were taken with a TDR equipment to a 20 cm depth, in a nearly flat 1.2 ha field at the Central Experimental Farm of the Agriculture Canada, Ottawa. The soil classified as a Rideau soil series, is a clay loam soil. A square grid with 10 m spacing was laid out, resulting in 164 sampling points at which two TDR rods were installed to measure the water content down to 20 cm depth. Measurements were taken on 33 dates during the frost free months in 1987, 1988 and 1989. The spatial variability was analyzed examining... Tipo: Info:eu-repo/semantics/article Palavras-chave: TDR; Temporal stability; Semivariogram; Geostatistics. Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052008000200022 Spatial and temporal variability of plant-parasitic nematodes population in sugarcane Bragantia Dinardo-Miranda,Leila Luci; Fracasso,Juliano Vilela. Nematodes are important pests of sugarcane crop in Brazil. However, no studies have been reported on the spatial and temporal variability of nematodes population in sugarcane fields and such studies are indispensable for the development of sampling plans, aimed at their application in integrated management programs. This work was carried out in two commercial fields of approximately 1 ha, both of them infested by Meloidogyne javanica and Pratylenchus zeae. In each area, samples represented by about 50 g of roots, were collected every two months, within a grid measuring 10.5 × 10 m (experiment 1) and 9.8 × 10 m (experiment 2). The highest nematodes populations were obtained during the rainy season, when high temperatures and moistures were favorable to root... Tipo: Info:eu-repo/semantics/article Palavras-chave: Saccharum; Meloidogyne; Pratylenchus; Semivariogram; Kriging. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500006 Spatial soil sampling design using apparent soil electrical conductivity measurements Bragantia Siqueira,Glécio Machado; Dafonte,Jorge Dafonte; González,Antonio Paz; Vázquez,Eva Vidal; Armesto,Monteserrat Valcarcel; Guedes Filho,Osvaldo. ABSTRACT Soil sampling is an important stage of digital soil mapping. The objective of this study was to characterize the spatial design of soil sampling using soil apparent electrical conductivity (ECa) and its optimized spatial sampling. For the characterization, it was used the Spatial Simulated Annealing (SSA) technique, incorporated on the software SANOS 0.1, and the method of response surface sampling design on the software ESAP 2.35. The ECa was measured at 1,887 points in an area of 6 ha located in the northwestern region of Spain. The EM38-DD equipment (Geonics Limited 2005) was used at 2 depths: vertical dipole (1.5 m effective measurement depth) and horizontal dipole (0.75 m effective measurement depth). Semivariogram showed trend for ECa in... Tipo: Info:eu-repo/semantics/article Palavras-chave: Geostatistics; Semivariogram; Spatial variability; Optimization; Soil sampling. Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052016000400459 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 Some aspects about the spatial dependence index for variability of soil attributes Ciência Rural Santos,Eduardo Lucas Ensslin dos; Seidel,Enio Júnior; Pazini,Juliano de Bastos; Oliveira,Marcelo Silva de; Appel Neto,Edemar; Barbosa,Ismael Canabarro. ABSTRACT: The main purpose of this article was to evaluate the behavior and relationship of the range and components of SDI (Spatial Dependence Index) in general and in function of field factors such as soil types, type of attribute and soil layers. This evaluation was based on real data collected in national journals. It was noticed that the parameter range, in general and for different field factors, presented asymmetric positive behavior. The components of the SDI showed approximately symmetrical behavior. The SDI can capture the range behavior more intensely (the spatial variability behavior in the horizontal direction of the semivariogram), and, in a less intense way, the behavior of the contribution and sill parameters (the spatial dependence... Tipo: Info:eu-repo/semantics/article Palavras-chave: Spatial dependence; Geostatistics; Semivariogram; Field factors. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000600252 Establishment of homogeneous zones in a soil of alluvial origin Ciência e Agrotecnologia Jaramillo-Barrios,Camilo Ignacio; Ortiz-Rico,Andrés Felipe; Carrillo,Gustavo Alfonso Araujo; Varón-Ramírez,Viviana Marcela. ABSTRACT Soils have the ability to maintain plant growth and biological activity due to their physical and chemical properties. The aim of this study was to observe the spatial distribution of some chemical properties of the soil, such as pH, organic matter (OM), electrical conductivity (EC), effective cation exchange capacity (ECEC), sulfur (S) and aluminum (Al) content and to establish zones with homogeneous chemical characteristics using the MULTISPATI-PCA technique and the fuzzy c-means algorithm. The study area was located in the Tundama and Sugamuxi Valleys (Boyacá, Colombia) with an area of ​​8,017 ha. Chemical properties such as pH, OM, EC, S, Al, and ECEC were indicators of the chemical degradation of these soils. Four homogeneous zones were... Palavras-chave: Geostatistics; Semivariogram; Soil degradation; Multispati-PCA; Spatial distribution.. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542019000100216 Registros recuperados: 31 Primeira ... 1 2 ... Última

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