<?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>2007-9028</journal-id>
<journal-title><![CDATA[Ecosistemas y recursos agropecuarios]]></journal-title>
<abbrev-journal-title><![CDATA[Ecosistemas y recur. agropecuarios]]></abbrev-journal-title>
<issn>2007-9028</issn>
<publisher>
<publisher-name><![CDATA[Universidad Juárez Autónoma de Tabasco, Dirección de Investigación y Posgrado]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-90282017000100031</article-id>
<article-id pub-id-type="doi">10.19136/era.a4n10.688</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[El carbono orgánico en Leptosols con distribución discontinua en la península de Yucatán]]></article-title>
<article-title xml:lang="en"><![CDATA[The organic carbon stock in Leptosls with discontinuous distribution in the Peninsula of Yucatan]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Delgado-Carranza]]></surname>
<given-names><![CDATA[Carmen]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Bautista-Zúñiga]]></surname>
<given-names><![CDATA[Francisco]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Calvo-Irabien]]></surname>
<given-names><![CDATA[Luz Ma.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Aguilar-Duarte]]></surname>
<given-names><![CDATA[Yameli Guadalupe]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Tellez]]></surname>
<given-names><![CDATA[Jazmín Guadalupe]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Centro de Investigaciones en Geografía Ambiental Laboratorio Universitario de Geofísica Ambiental]]></institution>
<addr-line><![CDATA[Morelia Michoacán]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Centro de Investigación Científica de Yucatán  ]]></institution>
<addr-line><![CDATA[Mérida Yucatán]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2017</year>
</pub-date>
<volume>4</volume>
<numero>10</numero>
<fpage>31</fpage>
<lpage>38</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-90282017000100031&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-90282017000100031&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-90282017000100031&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Para determinar el contenido del carbono orgánico en el suelo (COS) se requiere cuantificar la fracción gruesa (piedras y gravas), la densidad aparente (DA) y profundidad. El inventario de suelos del INEGI no reporta estos datos, por lo que los mapas de COS generan dudas. El objetivo del presente trabajo fue evaluar la variabilidad espacial del carbono orgánico del suelo a distancias cortas, así como los contenidos del carbono orgánico por unidad de área en suelos Leptosols del norte de la península de Yucatán. Se tomaron 102 muestras, para determinar el carbono orgánico por la técnica de dicromato de potasio; separando los fragmentos gruesos (grava gruesa, grava mediana y grava fina) de la tierra fina; el color se registró en seco y húmedo. La DA se midió con la cantidad de tierra fina en un volumen de 10 x 10 cm de super cie con profundidad variable hasta encontrar la roca; el análisis geoestadístico se realizó mediante kriging ordinario. Los suelos Leptosols presentaron valores de COS por debajo de 100 t ha-1, con valores medios de 32.85, 37.57, 43.72 y 61.93 t ha-1, para suelos pardos obscuros, pardos muy obscuros, negros y grises muy obscuros, respectivamente. Los fragmentos gruesos varían de 6.7 a 96.4 %, con promedio de 71.15 %. Se encontró que los valores de carbono orgánico del suelo son menores a los reportados en unidad de superficie.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: The soil organic carbon (SOC) content requires quantifying the coarse fraction (stones and gravels), bulk density and depth. The soils inventory realized for INEGI didn&#8217;t reports the first two parameters, then, the generated SOC maps have considerable doubt SOC. The objective was to evaluate the spatial variability of soil organic carbon over short distances, as well as to report the contents of organic carbon per unit area in Leptosols from northern of Yucatan Peninsula. 102 samples were taken; organic carbon was analyzed by technique of potassium dichromate; and coarse fragments (coarse gravel, medium and ne gravel) were separated from the ne earth. The Color was recorded dry and wet, bulk density was measured using the amount of ne earth in a volume of 10 x 10 cm surface by a depth to nd the rock. Leptosols presented SOC values below 100 t ha-1 reported for this area, with mean values of 32.85, 37.57, 43.72, and 61.93 t ha-1, for dark brown soils, very dark brown, blacks and very dark grays respectively. Coarse fragments ranging from 6.7 % to 96.4 % with an average of 71.15 %. It was found that the values of soil organic carbon obtained in this study are lower than those reported in unit area.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Materia orgánica]]></kwd>
<kwd lng="es"><![CDATA[fracción gruesa]]></kwd>
<kwd lng="es"><![CDATA[densidad aparente]]></kwd>
<kwd lng="es"><![CDATA[desarrollo edáfico]]></kwd>
<kwd lng="es"><![CDATA[geoestadística]]></kwd>
<kwd lng="en"><![CDATA[Organic matter]]></kwd>
<kwd lng="en"><![CDATA[coarse fraction]]></kwd>
<kwd lng="en"><![CDATA[bulk density]]></kwd>
<kwd lng="en"><![CDATA[soil development]]></kwd>
<kwd lng="en"><![CDATA[geostatistics]]></kwd>
</kwd-group>
</article-meta>
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