<?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>1659-4266</journal-id>
<journal-title><![CDATA[Cuadernos de Investigación UNED]]></journal-title>
<abbrev-journal-title><![CDATA[Cuadernos de Investigación UNED]]></abbrev-journal-title>
<issn>1659-4266</issn>
<publisher>
<publisher-name><![CDATA[Universidad Estatal a Distancia de Costa Rica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1659-42662023000200046</article-id>
<article-id pub-id-type="doi">10.22458/urj.v15i2.4656</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Características físicas, químicas y microbiológicas del agua subterránea en Los Chiles, Costa Rica, y su asociación con el uso del suelo]]></article-title>
<article-title xml:lang="en"><![CDATA[Physical, chemical, and microbiological characteristics of groundwater in Los Chiles, Costa Rica, and its association with land use]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Fuentes-Schweizer]]></surname>
<given-names><![CDATA[Paola]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mora]]></surname>
<given-names><![CDATA[Eric Morales]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Muñoz]]></surname>
<given-names><![CDATA[Rigoberto Vargas]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jiménez]]></surname>
<given-names><![CDATA[Kenia Barrantes]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jiménez]]></surname>
<given-names><![CDATA[Luz Chacón]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Costa Rica Facultad de Ciencias Básicas, Escuela de Química Centro de Investigaciones en Electroquímica y Energía Química]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad de Costa Rica Instituto de Investigaciones en Salud ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad de Costa Rica Facultad de Ciencias Básicas Escuela de Geología]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Universidad de Costa Rica Instituto de Investigaciones en Salud ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af5">
<institution><![CDATA[,Universidad de Costa Rica Instituto de Investigaciones en Salud ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2023</year>
</pub-date>
<volume>15</volume>
<numero>2</numero>
<fpage>46</fpage>
<lpage>58</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1659-42662023000200046&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1659-42662023000200046&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1659-42662023000200046&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Introducción: Los Chiles tiene uno de los índices de progreso social más bajos de Costa Rica. Los habitantes beben agua subterránea no tratada de un acuífero que atraviesa la frontera entre Nicaragua y Costa Rica. Objetivo: Caracterizar la calidad del agua y posibles asociaciones con el uso de la tierra. Métodos: Recolectamos seis muestras de agua de pozos durante las temporadas seca y lluviosa en 2019 y aplicamos pruebas estándar. Resultados: Los pastizales y el suelo descubierto cubren áreas más grandes que otros usos del suelo. El agua es del tipo calcio-bicarbonato, y sus valores físico-químicos son aceptables, no detectamos Escherichia coli en ninguna muestra, mientras que coliformes fecales sólo en La Trocha. Conclusión: Si se trata para eliminar los coliformes y se protege de otros efectos de la actividad humana, esta fuente será óptima para el consumo humano.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Introduction: Los Chiles has one of the lowest Social Progress Indexes in Costa Rica. The inhabitants drink untreated groundwater from an aquifer across the Nicaragua-Costa Rica border. Objective: To characterize water quality and possible associations with land use. Methods: We collected six water samples from wells during the dry and rainy seasons in 2019 and applied standard tests. Results: Grasslands and bare ground cover larger areas than other land uses. The water is calcic-bicarbonate type, and its physical-chemical values are acceptable, we did not detect Escherichia coli in any sample, while we only detected fecal coliforms in La Trocha. Conclusion: If treated to eliminate coliforms and protected from other effects of human activity, this water will be optimal for human consumption.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[groundwater]]></kwd>
<kwd lng="en"><![CDATA[environmental health]]></kwd>
<kwd lng="en"><![CDATA[waterborne diseases]]></kwd>
<kwd lng="en"><![CDATA[hydric resource.]]></kwd>
<kwd lng="es"><![CDATA[agua subterránea]]></kwd>
<kwd lng="es"><![CDATA[salud ambiental]]></kwd>
<kwd lng="es"><![CDATA[enfermedades transmitidas por el agua]]></kwd>
<kwd lng="es"><![CDATA[recurso hídrico.]]></kwd>
</kwd-group>
</article-meta>
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