<?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>0187-5779</journal-id>
<journal-title><![CDATA[Terra Latinoamericana]]></journal-title>
<abbrev-journal-title><![CDATA[Terra Latinoam]]></abbrev-journal-title>
<issn>0187-5779</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de la Ciencia del Suelo A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-57792014000200119</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Assessment of soil compaction under different management regimes using double-cycle uniaxial compression test]]></article-title>
<article-title xml:lang="es"><![CDATA[Evaluación de la compactación del suelo bajo diferentes prácticas de manejo utilizando una prueba de compresión uniaxial de doble ciclo]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vaca García]]></surname>
<given-names><![CDATA[Víctor Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Domínguez López]]></surname>
<given-names><![CDATA[Aurelio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González Huerta]]></surname>
<given-names><![CDATA[Andrés]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Morales Rosales]]></surname>
<given-names><![CDATA[Edgar Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Franco Mora]]></surname>
<given-names><![CDATA[Omar]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gutiérrez Rodríguez]]></surname>
<given-names><![CDATA[Francisco]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma del Estado de México Campus Universitario El Cerrillo Programa de Maestría y Doctorado en Ciencias Agropecuarias y Recursos Naturales]]></institution>
<addr-line><![CDATA[Toluca Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma del Estado de México Campus Universitario El Cerrillo Facultad de Ciencias Agrícolas]]></institution>
<addr-line><![CDATA[Toluca Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2014</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2014</year>
</pub-date>
<volume>32</volume>
<numero>2</numero>
<fpage>119</fpage>
<lpage>126</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792014000200119&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792014000200119&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792014000200119&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: The impact of wheeled farm machines trafficking on soil compaction has not been well documented in Mexico, particularly in the maize producing area of the Toluca-Atlacomulco Valley, which features a Vertisol soil type. In addition, laboratory measurements are needed that can imitate field conditions is needed to make measurements that are sensitive, reliable and appropriate for monitoring changes in compaction and other physical soil properties while reducing destructive sampling in the field. The objective of this research was to use double-cycle uniaxial compression, penetration resistance and cutting force tests to assess the response of a Vertisol in terms of hardness, cohesiveness and adhesiveness when compacted by wheel traffic in three different types of tillage systems: zero tillage (ZT), minimal tillage (MT) and conventional tillage (CT). The study was conducted in Toluca, State of Mexico, in 2011. Soil samples were collected from the tractor's wheel track, with three repetitions at two depths. All of the variables were measured using a universal testing machine. For penetration resistance and cutting force tests, standard screwdrivers were used as probes. According to the uniaxial compression test, CT was found to increase soil hardness, relative to the other systems (47% higher on average). MT reported the highest adhesiveness value (0.1 N s-1), but no statistically significant differences in cohesiveness were found among tillage systems. In the ZT system higher penetration resistance was observed in subsoil than in topsoil. MT obtained the maximum cutting force value (54.55 N), while there were no significant differences between other two systems. In these trials the universal testing machine was sensitive enough to detect differences in the soil physical properties of the different tillage systems.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: El impacto del tránsito rodado de maquinaria agrícola en la compactación del suelo ha sido poco documentado en México, particularmente en la zona productora de maíz del Valle Toluca-Atlacomulco, caracterizada por un tipo de suelo Vertisol. En adición, se requieren mediciones de laboratorio que imiten las condiciones de campo, reduciendo el muestreo destructivo, y que sean sensibles, confiables y apropiadas para monitorear cambios en la compactación y otras propiedades físicas del suelo. Esta investigación se planteó utilizar pruebas de compresión uniaxial, resistencia a la penetración y fuerza de corte, para evaluar la respuesta de un Vertisol, en términos de dureza, cohesividad y adhesividad, a la compactación por tránsito rodado en sistemas de labranza cero (LC), labranza mínima (LM) y labranza tradicional (LT). El estudio se realizó en Toluca, Estado de México, en 2011. Se obtuvieron muestras de suelo en la huella del tractor con tres repeticiones a dos niveles de profundidad. Todas las variables fueron medidas empleando una máquina universal de prueba. Para los ensayos de resistencia a la penetración y fuerza de corte, se utilizaron desarmadores estándar como sondas. De acuerdo con la prueba de compresión uniaxial, en comparación con los demás sistemas la LT incrementó la dureza del suelo (47% más en promedio), la LM reportó el valor más alto de adhesividad (0.1 N s-1), y no se encontraron diferencias estadísticas significativas en relación con la cohesividad entre sistemas. Se observó en el subsuelo mayor resistencia a la penetración en LC que a nivel superficial. La LM obtuvo el valor máximo de fuerza de corte (54.55 N), mientras que los otros sistemas no mostraron diferencias significativas entre ellos. Los ensayos con la máquina universal de prueba fueron suficientemente sensibles para detectar diferencias en las propiedades físicas del suelo de los diferentes sistemas de labranza.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[vertisol]]></kwd>
<kwd lng="en"><![CDATA[hardness]]></kwd>
<kwd lng="en"><![CDATA[adhesiveness]]></kwd>
<kwd lng="en"><![CDATA[cohesiveness]]></kwd>
<kwd lng="es"><![CDATA[vertisol]]></kwd>
<kwd lng="es"><![CDATA[dureza]]></kwd>
<kwd lng="es"><![CDATA[adhesividad]]></kwd>
<kwd lng="es"><![CDATA[cohesividad]]></kwd>
</kwd-group>
</article-meta>
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