<?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>0016-7169</journal-id>
<journal-title><![CDATA[Geofísica internacional]]></journal-title>
<abbrev-journal-title><![CDATA[Geofís. Intl]]></abbrev-journal-title>
<issn>0016-7169</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Geofísica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0016-71692022000100055</article-id>
<article-id pub-id-type="doi">10.22201/igeof.00167169p.2022.61.1.2188</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Complejación de metales por sustancias húmicas acuáticas como proceso natural, tomando como caso de estudio el Lago de Xochimilco, Ciudad de México, México]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González-Guadarrama]]></surname>
<given-names><![CDATA[María de Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Castillo-Blum]]></surname>
<given-names><![CDATA[Silvia Elena]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Armienta-Hernández]]></surname>
<given-names><![CDATA[María Aurora]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Facultad de Química ]]></institution>
<addr-line><![CDATA[Coyoacán Ciudad de México]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Geofísica Departamento de Recursos Naturales]]></institution>
<addr-line><![CDATA[Coyoacán Ciudad de México]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>03</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>03</month>
<year>2022</year>
</pub-date>
<volume>61</volume>
<numero>1</numero>
<fpage>55</fpage>
<lpage>65</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0016-71692022000100055&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0016-71692022000100055&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0016-71692022000100055&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen En este trabajo se presenta la importancia de la materia orgánica, específicamente Substancias Húmicas Acuáticas (SHA) dentro de la especiación y distribución de metales y nutrientes dentro de un sistema acuático, en este caso el Lago de Xochimilco, sitio con gran importancia ecológica, el cual, es hábitat natural de la especie endémica axolotl (ajolote). En esta investigación se realizaron reacciones de complejación entre las SHA y metales (Cu, Mn, Pb y Zn) bajo diferentes condiciones de pH, la fuente de las SHA corresponde con la muestra de agua tomada en el Lago de Xochimilco, en presencia o ausencia de disolución amortiguadora de pH, además de variar la concentración de los metales. Los resultados muestran que existe una competencia directa entre los elementos mayores y oligoelementos por reaccionar con las SHA; además, que bajo las condiciones de pH del Lago de Xochimilco es muy posible que se formen los compuestos complejos.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This work discusses the importance of organic matter, specifically Aquatic Humic Substances (SHA) within the speciation and distribution of metals within an aquatic system, in this case Xochimilco Lake, a site with great ecological importance. This lake is the natural habitat of the endemic species &#8220;axolotl&#8221; (ajolote). In this research, complexation reactions between SHA and metals (Cu, Mn, Pb and Zn) were carried out under different reaction conditions, the source of AHS was water samples taken in Xochimilco Lake in presence and absence of pH buffer dissolution and varying the concentration of metals. The results show that there is a direct competition between the major elements and trace elements to react with the AHS. Under the pH conditions of Xochimilco Lake complexes formation is possible.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Remediación]]></kwd>
<kwd lng="es"><![CDATA[substancias húmicas acuáticas]]></kwd>
<kwd lng="es"><![CDATA[metales]]></kwd>
<kwd lng="es"><![CDATA[reacciones de complejación y Lago de Xochimilco]]></kwd>
<kwd lng="en"><![CDATA[Remediation]]></kwd>
<kwd lng="en"><![CDATA[aquatic humic substances]]></kwd>
<kwd lng="en"><![CDATA[metals]]></kwd>
<kwd lng="en"><![CDATA[reactions of complexation and Xochimilco Lake]]></kwd>
</kwd-group>
</article-meta>
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