<?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>2215-3896</journal-id>
<journal-title><![CDATA[Revista de Ciencias Ambientales]]></journal-title>
<abbrev-journal-title><![CDATA[Ciencias Ambientales]]></abbrev-journal-title>
<issn>2215-3896</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2215-38962023000100010</article-id>
<article-id pub-id-type="doi">10.15359/rca.57-1.11</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Estudio del contenido materia orgánica por dos métodos analíticos en suelos de Honduras]]></article-title>
<article-title xml:lang="en"><![CDATA[Study of the content of organic matter by two analytical methods in Honduran soils]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Arévalo]]></surname>
<given-names><![CDATA[Gloria Elizabeth]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Sánchez-Amaya]]></surname>
<given-names><![CDATA[José Moisés]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Guillen-Marquina]]></surname>
<given-names><![CDATA[Ingrid]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Escuela Agrícola Panamericana  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Honduras</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad de Guadalajara  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Northern Virginia Community College  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>USA</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2023</year>
</pub-date>
<volume>57</volume>
<numero>1</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S2215-38962023000100010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S2215-38962023000100010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S2215-38962023000100010&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  (Introducción):  el método más común para determinar el contenido de materia orgánica del suelo es el WalkleyBlack, pero este presenta desventajas medioambientales por el uso del tóxico dicromato de potasio; como alternativa, surge el método de pérdidas por ignición. Ambos métodos presentan resultados significativamente diferentes debido a que el método de ignición puede reportar datos mayores por la presencia de arcillas y por considerar todo el contenido orgánico de la muestra, a diferencia de Walkley-Black, que considera únicamente, los compuestos de cadenas más largas.  (Objetivo):  Se determinó la relación que existe entre el contenido de materia orgánica por Walkley-Black y perdidas por ignición considerando el contenido de arcilla.  (Metodología):  Se estudiaron 60 muestras de suelo del nororiente y centro de Honduras. El contenido de arcilla fue determinado a través del método de Bouyoucos. La materia orgánica se determinó por el método de Walkley-Black y por el método de ignición siguiendo lo establecido por los estándares internacionales de AASHTO T 194-97 (2018) y AASHTO T 267-86 (2013), respectivamente.  (Resultados):  Se encontró una relación lineal válida entre el contenido de materia orgánica determinado por Walkley-Black y por perdidas por ignición independiente del contenido de arcilla. Fue posible establecer un rango de interpretación del contenido de materia orgánica para el método de pérdidas por ignición a partir de los rangos de interpretación típicos reportados para el contenido de materia orgánica de WalkleyBlack.  (Conclusiones):  Los resultados de este estudio demostraron que es posible usar el método por ignición como alternativa al método Walkley-Black.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  (Introduction):  The most common method to determine the organic matter content of soil is the &#8220;Walkley-Black&#8221; method, but this method has environmental disadvantages due to the use of the toxic potassium dichromate. As an alternative, the loss on ignition method arises. Both present significantly different results because the ignition method can report higher data due to the presence of clays and because it considers all the organic content of the sample, unlike Walkley-Black method, which considers only the compounds with longer chains.  (Objective):  The relationship between the organic matter content determined by Walkley-Black and loss on ignition was determined considering the clay content.  (Methodology):  60 soil samples from northeastern and central Honduras were studied. The clay content was determined through the Bouyoucos method. The organic matter content was determined by the Walkley-Black method and by the ignition method following the guidelines by the international standards AASHTO T 194-97 (2018) and AASHTO T 267-86 (2013), respectively.  (Results):  A valid linear relationship was found between the organic matter content determined by Walkley-Black and the loss on ignition regardless of the clay content. It was possible to establish an interpretation range for organic matter content for the loss on ignition method from the typical interpretation ranges reported for Walkley-Black organic matter content.  (Conclusions):  The results of this study showed that it is possible to use the ignition method as an alternative to Walkley-Black.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[dicromato]]></kwd>
<kwd lng="es"><![CDATA[materia orgánica]]></kwd>
<kwd lng="es"><![CDATA[pérdidas por ignición]]></kwd>
<kwd lng="es"><![CDATA[Walkley-Black]]></kwd>
<kwd lng="en"><![CDATA[Dichromate]]></kwd>
<kwd lng="en"><![CDATA[loss on ignition]]></kwd>
<kwd lng="en"><![CDATA[organic matter]]></kwd>
<kwd lng="en"><![CDATA[Walkley-Black]]></kwd>
</kwd-group>
</article-meta>
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