<?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>S2007-90282018000200293</article-id>
<article-id pub-id-type="doi">10.19136/era.a5nl4.1515</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Hydrodynamics and measurement of natural currents in a plain river using acoustic Doppler equipment]]></article-title>
<article-title xml:lang="es"><![CDATA[Hidrodinámica y medición de corrientes naturales en un río de planicie utilizando equipos acústicos Doppler]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Priego-Hernández]]></surname>
<given-names><![CDATA[Gastón]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rubio-Arias]]></surname>
<given-names><![CDATA[Héctor]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rivera-Trejo]]></surname>
<given-names><![CDATA[Fabián]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Juárez Autónoma de Tabasco División Académica de Ciencias Básicas ]]></institution>
<addr-line><![CDATA[Cunduacán Tabasco]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma de Chihuahua Facultad de Zootecnia y Ecología Departamento de Recursos Naturales]]></institution>
<addr-line><![CDATA[Chihuahua ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad Juárez Autónoma de Tabasco División Académica de Ingeniería y Arquitectura ]]></institution>
<addr-line><![CDATA[Cunduacán Tabasco]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<volume>5</volume>
<numero>14</numero>
<fpage>293</fpage>
<lpage>301</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-90282018000200293&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-90282018000200293&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-90282018000200293&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT: Flow discharge and hydrodynamic field measurements are essential data for understanding aquatic ecosystems. The objective of this study was to compare the use of three Acoustic Doppler Current Profilers (ADCPs) in measuring flow discharge and hydrodynamics in the Carrizal River located in southeastern Mexico. The evaluated ADCPs operate on frequencies of 2 000 kHz, 1 500 kHz and 600 kHz. The measurements were carried out in a 100-m-wide cross section, five times each for each ADCP, within an estimated time of 5 min. The obtained data were: 1) flow velocity components; 2) depth; 3) transversal distance between each vector; 4) total distance of the cross section and; 5) geographic position of each vector. Tecplot® graphics were made with the collected information. The results showed that velocity magnitudes were low in bank areas, while high in the center. For a 5-m depth range, the 2 000-kHz ADCP keeps a more homogenous velocity distribution in comparison with the other equipment. The results showed that discharge measurements varied by no more than 5% among ADCPs. It is concluded that the most important variable in choosing an ADCP for a hydrodynamic study is its operating frequency.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN: El aforo de corrientes y el mapeo de campos de velocidad, es información esencial para el entendimiento de los ecosistemas acuáticos. El objetivo del estudio fue comparar tres perfiladores acústicos Doppler, también conocidos como ADCP (Acoustic Doppler Current Profiler), en el río Carrizal localizado en el Sureste mexicano. Los equipos ADCP evaluados operan en frecuencias de 2 000 kHz, 1 500 kHz y 600 kHz. La medición se efectuó en una sección transversal de 100 m de ancho, realizando cinco recorridos con cada equipo con una duración aproximada de 5 min. Se registró información de: 1) componentes de velocidad del flujo, 2) profundidad, 3) distancia transversal entre cada vector, 4) distancia total de la sección transversal y 5) posición geográfica de cada vector. Con la información obtenida se elaboraron gráficas en Tecplot®. Los resultados muestran que las magnitudes de velocidad fueron bajas en la zona de márgenes, mientras que las altas en el centro de la sección. Para un rango de profundidad de 5 m, el ADCP de 2 000 kHz tuvo una distribución de velocidad más detallada al compararla con los otros dos equipos. Los gastos medidos con cada equipo no variaron en más de un 5%. La generación del campo de velocidades, es la variable más importante al seleccionar un ADCP es su frecuencia de operación.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Doppler equipment]]></kwd>
<kwd lng="en"><![CDATA[operating frequency]]></kwd>
<kwd lng="en"><![CDATA[hydrodynamics]]></kwd>
<kwd lng="en"><![CDATA[flow discharge]]></kwd>
<kwd lng="es"><![CDATA[Equipo Doppler]]></kwd>
<kwd lng="es"><![CDATA[frecuencia de operación]]></kwd>
<kwd lng="es"><![CDATA[hidrodinámica]]></kwd>
<kwd lng="es"><![CDATA[aforo líquido]]></kwd>
</kwd-group>
</article-meta>
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<article-title xml:lang=""><![CDATA[Flow velocity profiles in the Lower Scheldt estuary]]></article-title>
<source><![CDATA[Ocean Dynamics]]></source>
<year>2006</year>
<volume>56</volume>
<page-range>284-94</page-range></nlm-citation>
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</article>
