<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0012-7353</journal-id>
<journal-title><![CDATA[DYNA]]></journal-title>
<abbrev-journal-title><![CDATA[Dyna rev.fac.nac.minas]]></abbrev-journal-title>
<issn>0012-7353</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0012-73532019000200289</article-id>
<article-id pub-id-type="doi">10.15446/dyna.v86n209.70897</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Variabilidad espacial del pH del suelo muestreado por dos metodologías utilizadas en agricultura de precisión en granjas bajo rotación de cultivos]]></article-title>
<article-title xml:lang="en"><![CDATA[Spatial variability of soil pH sampled by two methodologies used in precision agriculture in farms under crop rotation]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ferraz]]></surname>
<given-names><![CDATA[Gabriel Araújo e Silva]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Barbosa]]></surname>
<given-names><![CDATA[Brenon Diennevan Souza]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Reynaldo]]></surname>
<given-names><![CDATA[Étore Francisco]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Santos]]></surname>
<given-names><![CDATA[Sthéfany Airane dos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gonçalves]]></surname>
<given-names><![CDATA[Jose Roberto Moreira Ribeiro]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ferraz]]></surname>
<given-names><![CDATA[Patrícia Ferreira Ponciano]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Federal University of Lavras Department of Agricultural Engineering ]]></institution>
<addr-line><![CDATA[Lavras ]]></addr-line>
<country>Brazil</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Specialist in Equipment at Monsanto  ]]></institution>
<addr-line><![CDATA[Brazil ]]></addr-line>
<country>Brazil</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,University Center Augusto Motta  ]]></institution>
<addr-line><![CDATA[Rio de Janeiro ]]></addr-line>
<country>Brazil</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2019</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2019</year>
</pub-date>
<volume>86</volume>
<numero>209</numero>
<fpage>289</fpage>
<lpage>297</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0012-73532019000200289&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0012-73532019000200289&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0012-73532019000200289&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen El objetivo de este estudio fue caracterizar la variabilidad espacial del pH para suelos de dos fincas en el estado de Paraná, Brasil, con base en dos métodos diferentes de muestreo utilizados en agricultura de precisión, mediante análisis geoestaddísticos. El primero método de muestreo del pH consistió en la colecta de muestras de suelo por ele método tradicional (1punto/ha). El segundo método de determinación del pH fue el sensor de suelo dinâmico (200 puntos / ha). El modelo esférico fue más adecuado para la mayoría de los semivariogramas, independientemente del método de muestreo. La mejor distribución espacial fue obtenida por la cualidad del muestreado del sensor de suelo dinâmico. El número de muestras del pH colectadas y el método de muestreo influyeron en la representación visual de la variabilidad del pH.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This study aimed to characterize the spatial variability of pH in soils of two farms in the state of Paraná, Brazil, based on two different sampling methods used in precision agriculture, by means of geostatistical analyzes. The first method of sampling the pH grid consisted in the collection of soil samples by the traditional method (1 point / ha). The second method of pH determination was by on-the-go soil sensor (200 points / ha). The spherical model was better suited to most semivariograms, regardless of the sampling method. After adjusting the semivariograms for soil pH determination methods, thematic maps were made using normal kriging. The best spatial distribution of pH was obtained where the attribute was sampled by the on-the-go sensor. The number of pH samples collected and the sampling method influenced the visual representation of pH variability.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[spatial variability]]></kwd>
<kwd lng="en"><![CDATA[mobile contact sensor]]></kwd>
<kwd lng="en"><![CDATA[grid sampling]]></kwd>
<kwd lng="en"><![CDATA[geostatistics]]></kwd>
<kwd lng="es"><![CDATA[variabilidad espacial]]></kwd>
<kwd lng="es"><![CDATA[sensor de contacto móvil]]></kwd>
<kwd lng="es"><![CDATA[muestreo en cuadrícula]]></kwd>
<kwd lng="es"><![CDATA[geoestadística]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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