<?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>S0187-57792015000300199</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Variabilidad espacial del carbono en un suelo después de 10 años de retiro e incorporación de residuos de cosecha]]></article-title>
<article-title xml:lang="en"><![CDATA[Spatial variability of carbon in soil after 10 years of incorporating and removing harvest residues]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Acevedo]]></surname>
<given-names><![CDATA[David Cristóbal]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández Acosta]]></surname>
<given-names><![CDATA[Elizabeth]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Maldonado Torres]]></surname>
<given-names><![CDATA[Ranferi]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Álvarez Sánchez]]></surname>
<given-names><![CDATA[María Edna]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma Chapingo Departamento de Suelos ]]></institution>
<addr-line><![CDATA[Chapingo Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>09</month>
<year>2015</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>09</month>
<year>2015</year>
</pub-date>
<volume>33</volume>
<numero>3</numero>
<fpage>199</fpage>
<lpage>208</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792015000300199&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792015000300199&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792015000300199&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Determinar con exactitud el comportamiento del carbono orgánico del suelo, cuando se utilizan agroquímicos y se retiran los residuos de cosecha (manejo convencional, MC) y cuando los residuos de cosecha se incorporan al suelo sin el uso de agroquímicos (manejo orgánico, MO) tiene implicaciones ambientales y productivas. Para evaluar el efecto del MO y MC, sobre la densidad aparente del suelo (DAP), el carbono orgánico del suelo (COS) y el carbono capturado por el suelo (CCS), se llevó a cabo un experimento en parcelas cultivadas con maíz durante 10 años. Al final de los 10 años se efectuó un muestreo sistemático con espaciamientos de 5 m; se tomaron 152 muestras en la parcela orgánica y 72 en la parcela convencional determinando la DAP, COS y CCS. Con los datos obtenidos se analizó el comportamiento de cada variable por medio de técnicas de estadística clásica y geoestadística. El MO presentó un mayor % de COS y cantidad de CCS, así como una menor DAP en comparación con el MC; aunque desde el punto de vista estadístico no se tuvo efecto significativo (P &gt; 0.05) por estas prácticas. El MO incrementó la variabilidad estadística del COS y el CCS, y no afecto la variabilidad estadística de la DAP. La variabilidad espacial del COS y el CCS expresada mediante los semivariogramas y los mapas de isovalores coincidió con la variabilidad expresada por los coeficientes de variación, dados por la estadística clásica. La estructura espacial del COS y del CCS denotada por el semivariograma experimental, fue semejante para el MO y el MC. El MO provocó un incremento en la estructura espacial del COS y CCS y no tuvo efecto sobre la DAP.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: Accurately determining the behavior of soil organic carbon when agrochemicals are used and crop residues are removed (Conventional Management, CM) and when crop residues are incorporated into the soil and agrochemicals are not used (Organic Management, OM) has environmental and productive implications. To evaluate the effect of OM and CM on soil bulk density (SBD), soil organic carbon (SOC) and carbon sequestered by the soil (CSS), an experiment was conducted in plots planted with corn for 10 years. At the end of 10 years systematic sampling at a spacing of 5 m was performed: 152 samples in the organic plot and 72 in the conventional plot to determine SBD, SOC and CSS. With the data obtained, the behavior of each variable was analyzed using techniques of classical statistics and geostatistics. OM showed a higher percentage of SOC, a greater amount of CSS and a smaller SBD compared with CM, but there was no statistically significant effect (P &gt; 0.05) of these practices. OM increased statistical variability of SOC and CSS, but did not affect the statistical variability of the SBD. Spatial variability of SOC and CSS expressed through semivariogram and isovalue maps coincided with variability expressed by the coefficients of variation, given by classical statistics. The spatial structure of SOC and CSS denoted by the experimental semivariogram was similar to the OM and CM. OM caused an increase in the spatial structure of SOC and CSS but had no effect on SBD.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[densidad aparente]]></kwd>
<kwd lng="es"><![CDATA[maíz]]></kwd>
<kwd lng="es"><![CDATA[muestreo de suelos]]></kwd>
<kwd lng="es"><![CDATA[semivariogramas]]></kwd>
<kwd lng="en"><![CDATA[bulk density]]></kwd>
<kwd lng="en"><![CDATA[corn]]></kwd>
<kwd lng="en"><![CDATA[soil sampling]]></kwd>
<kwd lng="en"><![CDATA[semivariograms]]></kwd>
</kwd-group>
</article-meta>
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