<?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>1405-3322</journal-id>
<journal-title><![CDATA[Boletín de la Sociedad Geológica Mexicana]]></journal-title>
<abbrev-journal-title><![CDATA[Bol. Soc. Geol. Mex]]></abbrev-journal-title>
<issn>1405-3322</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Geológica Mexicana A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1405-33222020000200010</article-id>
<article-id pub-id-type="doi">10.18268/bsgm2020v72n2a220819</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Combinando árboles de decisión y métodos geoestadísticos para estimar la relación del mercurio total con propiedades químicas del suelo en el distrito minero de San Joaquín, Querétaro, México]]></article-title>
<article-title xml:lang="en"><![CDATA[Combining decision trees and geostatistical methods to estimate the relation between total mercury and soil chemical properties in the San Joaquín mining district, Querétaro, Mexico]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Trinidad]]></surname>
<given-names><![CDATA[Sergio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández-Silva]]></surname>
<given-names><![CDATA[Gilberto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Solís-Valdez]]></surname>
<given-names><![CDATA[Sara]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cruz-Cárdenas]]></surname>
<given-names><![CDATA[Gustavo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Trinidad]]></surname>
<given-names><![CDATA[Tomás]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Colegio de Postgraduados  ]]></institution>
<addr-line><![CDATA[Puebla Puebla]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,UNAM Centro de Geociencias ]]></institution>
<addr-line><![CDATA[Juriquilla Querétaro]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Instituto Politécnico Nacional  ]]></institution>
<addr-line><![CDATA[Michoacán Michoacán]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Colegio de Postgraduados Postgrado Forestal ]]></institution>
<addr-line><![CDATA[ Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<volume>72</volume>
<numero>2</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1405-33222020000200010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1405-33222020000200010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1405-33222020000200010&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen El grado de contaminación de un sitio, debido a la deposición de mercurio proveniente de los terreros de mina, está relacionada directamente con las propiedades del suelo, ya que éstas determinan la movilidad de los contaminantes. El objetivo de este trabajo fue determinar la relación del mercurio total con las propiedades del suelo, empleando el análisis de regresión con árboles de decisión y métodos geoestadísticos. Se colectaron 102 muestras superficiales para análisis de mercurio total y 10 propiedades del suelo. El análisis de regresión con árboles de decisión mostró cuatro relaciones entre el mercurio total y las propiedades químicas: 1) pH &gt; 8.5: mercurio total &gt; 64 mg/kg; 2) materia orgánica &gt; 5.5%: mercurio total &gt; 19 mg/kg; 3) bicarbonatos &gt; 256 mg/kg: mercurio total &gt; 77 mg/kg; y 4) potencial redox &gt; 171 mV: mercurio total &lt; 49 mg/kg. Además, se encontró una correspondencia entre la regresión con árboles de decisión y los mapas elaborados con métodos geoestadísticos. Por ejemplo, en lugares con mayores concentraciones de mercurio total, hay una mayor cantidad de materia orgánica, pH y bicarbonatos, en cambio, en los lugares con menores concentraciones de mercurio total, hubo mayor nivel de potencial redox. Se concluye que: i) los altos contenidos de materia orgánica favorecen la retención del mercurio total, ii) los valores pH de neutros a alcalinos ayudan a la poca movilidad, iii) los bicarbonatos favorecen la estabilización del mercurio total y iv) un potencial redox intermedio proporciona al suelo estabilidad frente a la contaminación del mercurio total.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract The degree of contamination of a site, due to the deposition of mercury from mine tailings, is directly related to soil properties since these determine the mobility of pollutants. The objective of this work was to determine the relationship between soil properties and total mercury, using classification and regression tree analysis, and geostatistical methods. A total of 102 samples were collected to measure total mercury and 10 soil-properties analysis. The regression analysis with decision trees showed four relationships between total mercury and chemical properties: 1) pH &gt; 8.5: total mercury &gt; 64 mg/kg; 2) organic matter &gt; 5.5%: total mercury &gt; 19 mg/kg; 3) bicarbonates &gt; 256 mg/kg: total mercury &gt; 77 mg/ kg; and 4) redox potential &gt; 171 mV: total mercury &lt; 49 mg/kg. In addition, a relationship was found between the regression decision trees and the maps elaborated with the geostatistical methods. For example, in places with higher concentrations of total mercury, there is a greater amount of organic matter, pH, and bicarbonates; however, there was higher redox potential in the lower concentrations of total mercury. In conclusion 1) high organic matter contents favor the retention of mercury, 2) neutral- alkaline pH favors low mobility of mercury, 3) bicarbonates favors mercury stabilization, and 4) intermediate redox potential provides soil stability to mercury pollution.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Mercurio total]]></kwd>
<kwd lng="es"><![CDATA[propiedades del suelo]]></kwd>
<kwd lng="es"><![CDATA[árboles de decisión]]></kwd>
<kwd lng="es"><![CDATA[geoestadística]]></kwd>
<kwd lng="en"><![CDATA[Total mercury]]></kwd>
<kwd lng="en"><![CDATA[soil properties]]></kwd>
<kwd lng="en"><![CDATA[decision tree analysis]]></kwd>
<kwd lng="en"><![CDATA[geostatistics]]></kwd>
</kwd-group>
</article-meta>
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