<?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>1405-3195</journal-id>
<journal-title><![CDATA[Agrociencia]]></journal-title>
<abbrev-journal-title><![CDATA[Agrociencia]]></abbrev-journal-title>
<issn>1405-3195</issn>
<publisher>
<publisher-name><![CDATA[Colegio de Postgraduados]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1405-31952007000400447</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Balance de calor e interacción agua-nutrientes-cadena alimenticia en el lago de Zapotlán, México]]></article-title>
<article-title xml:lang="en"><![CDATA[Heat balance and water-nutrient food chain interactions in lake Zapotlán, México]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ortiz-Jiménez]]></surname>
<given-names><![CDATA[Mario A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Anda]]></surname>
<given-names><![CDATA[José de]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Tecnológico de Tepic  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A. C.  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2007</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2007</year>
</pub-date>
<volume>41</volume>
<numero>4</numero>
<fpage>447</fpage>
<lpage>458</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1405-31952007000400447&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1405-31952007000400447&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1405-31952007000400447&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Se presenta un balance de calor del Lago de Zapotlán que fue resuelto numéricamente mediante el método de Runge-Kutta de cuarto orden con un incremento de tiempo de un día. A semejanza de otros lagos tropicales, el presupuesto anual de calor es muy bajo. La temperatura del lago (correlacionada con la radiación atmosférica y la radiación de fondo), la acción del viento (correlacionada con la radiación solar), y los escurrimientos (correlacionados con la radiación atmosférica, la radiación de fondo, la precipitación sobre el lago y la temperatura del lago), producen el mezclado del lago durante las estaciones de invierno, primavera y verano. Pero en el inicio del otoño, al disminuir el flujo neto de calor superficial y terminar las lluvias, el hipolimnión se enfría levemente debido a que esta capa es ocupada por escurrimientos más fríos y más densos. Esta pequeña diferencia térmica provoca que la columna de agua se estratifique de manera inestable. Los episodios alternados de mezclado y estratificado afectan significativamente el ciclo de nutrientes y la dinámica de la cadena alimenticia del lago.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This paper presents a heat balance for Lake Zapotlán, which was solved numerically using the fourth-order Runge-Kutta method with a step size of one day. Like other tropical lakes, the annual heat budget of Lake Zapotlán is very low. Lake temperature (correlated with both atmospheric longwave radiation and water back radiation), wind strength (correlated with solar shortwave radiation, and runoffs (correlated with atmospheric longwave radiation, water back radiation, precipitation on lake and lake temperature) produce lake mixing during three seasons: winter, spring and summer. When fall begins, as the net surface heat flux diminishes and rainfall ends, the epilimnion is slightly cooled since this layer receives colder, denser runoff. This small difference in temperature causes the water column to stratify in an unstable manner. The alternating episodes of mixing and stratification significantly affect the nutrient cycle and the dynamics of the food chain.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Estratificación]]></kwd>
<kwd lng="es"><![CDATA[método de Runge-Kutta de cuarto orden]]></kwd>
<kwd lng="es"><![CDATA[mezclado]]></kwd>
<kwd lng="es"><![CDATA[radiación atmosférica]]></kwd>
<kwd lng="es"><![CDATA[radiación de fondo]]></kwd>
<kwd lng="en"><![CDATA[Stratification]]></kwd>
<kwd lng="en"><![CDATA[fourth-order Runge-Kutta method]]></kwd>
<kwd lng="en"><![CDATA[mixing]]></kwd>
<kwd lng="en"><![CDATA[atmospheric radiation]]></kwd>
<kwd lng="en"><![CDATA[water back radiation]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Alcamo]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Henrichs]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Critical regions: A modelbased estimation of world water resources sensitive to global changes]]></article-title>
<source><![CDATA[Aquat. Sci.]]></source>
<year>2002</year>
<volume>64</volume>
<page-range>352-62</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Allen]]></surname>
<given-names><![CDATA[R. G.]]></given-names>
</name>
<name>
<surname><![CDATA[Pereira]]></surname>
<given-names><![CDATA[L. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Smith]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Crop evapotranspiration -Guidelines for computing crop water requirements]]></source>
<year>1998</year>
<page-range>300</page-range><publisher-loc><![CDATA[Rome ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Brady]]></surname>
<given-names><![CDATA[D. K.]]></given-names>
</name>
<name>
<surname><![CDATA[Graves]]></surname>
<given-names><![CDATA[W. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Geyer]]></surname>
<given-names><![CDATA[J. C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Surface Heat Exchange at Power Plant Cooling Lakes, Water Cooling Discharge Project Report, No. 5]]></source>
<year>1969</year>
<page-range>153</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Edison Electric Inst.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="">
<collab>CEASJ (Comisión Estatal de Agua y Saneamiento. Jalisco)</collab>
<source><![CDATA[Plan Maestro de la Laguna de Zapotlán]]></source>
<year>2003</year>
<page-range>111</page-range><publisher-loc><![CDATA[Ciudad Guzmán, Jal. ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chapman]]></surname>
<given-names><![CDATA[L. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Chapman]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Crisman]]></surname>
<given-names><![CDATA[T. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Nordlie]]></surname>
<given-names><![CDATA[F. G.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Dissolved oxygen and thermal regimes of a Ugandan crater lake]]></article-title>
<source><![CDATA[Hydrobiologia]]></source>
<year>1998</year>
<volume>385</volume>
<page-range>201-11</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chapra]]></surname>
<given-names><![CDATA[S. C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Surface Water-Quality Modeling]]></source>
<year>1997</year>
<page-range>844</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[WCB/McGraw-Hill]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chapra]]></surname>
<given-names><![CDATA[S. C.]]></given-names>
</name>
<name>
<surname><![CDATA[Canale]]></surname>
<given-names><![CDATA[R. P.]]></given-names>
</name>
</person-group>
<source><![CDATA[Numerical Methods for Engineers]]></source>
<year>1988</year>
<edition>2</edition>
<page-range>812</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[McGraw-Hill]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="book">
<collab>CNA (Comisión Nacional del Agua)</collab>
<source><![CDATA[Reportes meteorológicos mensuales]]></source>
<year>2004</year>
<page-range>30</page-range><publisher-loc><![CDATA[México ]]></publisher-loc>
<publisher-name><![CDATA[Estación Metereorológica de Ciudad Guzmán. Comisión Nacional del Agua]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="">
<collab>CUSUR (Centro Universitario del Sur)</collab>
<article-title xml:lang=""><![CDATA[2° Curso-Taller Internacional Rehabilitación de la &#8220;Laguna de Zapotlán&#8221;]]></article-title>
<source><![CDATA[Pesca y Limnología del Lago de Zapotlán]]></source>
<year>2002</year>
<page-range>24</page-range><publisher-loc><![CDATA[Ciudad Guzmán, Jalisco ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Dodds]]></surname>
<given-names><![CDATA[W. K.]]></given-names>
</name>
</person-group>
<source><![CDATA[Freshwater Ecology: Concepts and Environmental Applications]]></source>
<year>2002</year>
<page-range>569</page-range><publisher-loc><![CDATA[San Diego ]]></publisher-loc>
<publisher-name><![CDATA[Academic Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Guzmán]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Michel]]></surname>
<given-names><![CDATA[J. G.]]></given-names>
</name>
<name>
<surname><![CDATA[Peredo]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[García]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Camarena]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Limnología de la Laguna de Zapotlán]]></source>
<year>2000</year>
<page-range>120</page-range><publisher-loc><![CDATA[Zapopan, Jalisco ]]></publisher-loc>
<publisher-name><![CDATA[Centro Universitario de Ciencias Biológicas y Agropecuarias. Universidad de Guadalajara]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hamilton]]></surname>
<given-names><![CDATA[S. K.]]></given-names>
</name>
<name>
<surname><![CDATA[Lewis Jr.]]></surname>
<given-names><![CDATA[W. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Causes of seasonality in the chemistry of a lake on the Orinoco River foodplain, Venezuela]]></article-title>
<source><![CDATA[Limnol. Oceanogr.]]></source>
<year>1987</year>
<volume>32</volume>
<page-range>1277-90</page-range></nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="">
<collab>INEGI (Instituto Nacional de Estadística, Geografía e Informática)</collab>
<source><![CDATA[Tabulados Básicos]]></source>
<year>2001</year>
<publisher-loc><![CDATA[Jalisco ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Josey]]></surname>
<given-names><![CDATA[S. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Pascal]]></surname>
<given-names><![CDATA[R. W.]]></given-names>
</name>
<name>
<surname><![CDATA[Taylor]]></surname>
<given-names><![CDATA[P. K.]]></given-names>
</name>
<name>
<surname><![CDATA[Yelland]]></surname>
<given-names><![CDATA[M. J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes]]></article-title>
<source><![CDATA[J. Geophys. Res.]]></source>
<year>2003</year>
<volume>108</volume>
<page-range>3108</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lewis]]></surname>
<given-names><![CDATA[W. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Tropical Lakes: How Latitude Makes a Difference]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Schiemer]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Boland]]></surname>
<given-names><![CDATA[K. T.]]></given-names>
</name>
</person-group>
<source><![CDATA[Perspectives in Tropical Limnology]]></source>
<year>1996</year>
<page-range>43-64</page-range><publisher-loc><![CDATA[Amsterdam ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lubin]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The Role of the Tropical Super Greenhouse Effect in Heating the Ocean Surface]]></article-title>
<source><![CDATA[Science]]></source>
<year>1994</year>
<volume>265</volume>
<page-range>224-7</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martin]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
<name>
<surname><![CDATA[McCutcheon]]></surname>
<given-names><![CDATA[S. C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Hydrodynamics and Transport for Water Quality Modeling]]></source>
<year>1999</year>
<page-range>794</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Lewis Publisher]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="book">
<collab>Microsoft®</collab>
<source><![CDATA[Excel. 2000. Copyright© 1995-1999]]></source>
<year></year>
<publisher-name><![CDATA[Microsoft Corporation]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Orozco-Hernández]]></surname>
<given-names><![CDATA[R. B]]></given-names>
</name>
<name>
<surname><![CDATA[Guzmán-Arroyo]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Palma-Colín]]></surname>
<given-names><![CDATA[B. G.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Dípteros Acuáticos en la Ensenada de San Nicolás, Lago de Chapala]]></article-title>
<source><![CDATA[An. Inst. Cienc. Mar y Limnol.]]></source>
<year>1992</year>
<volume>20</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>25-32</page-range><publisher-name><![CDATA[Univ. Nal. Auton. México]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ortiz-Jiménez]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Anda]]></surname>
<given-names><![CDATA[J. De]]></given-names>
</name>
<name>
<surname><![CDATA[Shear]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Hydrologic Balance of Lake Zapotlán (México)]]></article-title>
<source><![CDATA[J. Environ. Hydrology]]></source>
<year>2005</year>
<volume>13</volume>
<page-range>1-16</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ortiz-Jiménez]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Anda]]></surname>
<given-names><![CDATA[J. De]]></given-names>
</name>
<name>
<surname><![CDATA[Shear]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Nutrients/Food Chain Model for Lake Zapotlán (México)]]></article-title>
<source><![CDATA[Intl. J. River Basin Manag.]]></source>
<year>2006</year>
<volume>4</volume>
<page-range>125-35</page-range></nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Oswald]]></surname>
<given-names><![CDATA[C. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Rouse]]></surname>
<given-names><![CDATA[W. R.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Thermal characteristics and energy balance of various-size Canadian shield lakes in the Mackenzie River Basin]]></article-title>
<source><![CDATA[J. Hydrometeorology]]></source>
<year>2004</year>
<volume>5</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>129-44</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Raudkivi]]></surname>
<given-names><![CDATA[A. J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Hydrology]]></source>
<year>1979</year>
<page-range>479</page-range><publisher-loc><![CDATA[Oxford ]]></publisher-loc>
<publisher-name><![CDATA[Pergamon]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Roberts]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Zalewsky]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[Swanson]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Sullivan]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Sinclair]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[LeMoine]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Quality Assurance Project Plan. Deschutes River, Capitol Lake, and Budd Inlet Temperature, Fecal Coliform Bacteria, Dissolved Oxygen, pH, and Fine Sediment Total Maximum Daily Load Study]]></source>
<year>2004</year>
<page-range>82</page-range><publisher-loc><![CDATA[Olympia, Washington ]]></publisher-loc>
<publisher-name><![CDATA[Washington State Department of Ecology. Environmental Assessment Program]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B25">
<nlm-citation citation-type="book">
<collab>UDG (Universidad de Guadalajara)</collab>
<source><![CDATA[Plan Parcial para el Desarrollo Integral de la Zona de la Laguna de Zapotlán]]></source>
<year>2002</year>
<publisher-loc><![CDATA[Municipio de Zapotlán el Grande. Municipio de Gómez Farias. Jalisco ]]></publisher-loc>
<publisher-name><![CDATA[Centro Universitario del Sur. Centro Universitario de Ciencias Sociales y Humanidades. Centro de Investigaciones del Medio Ambiente y Ordenación Territorial]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B26">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Wetzel]]></surname>
<given-names><![CDATA[R. G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Limnology: Lake and River Ecosystems]]></source>
<year>2001</year>
<edition>3</edition>
<page-range>850</page-range><publisher-loc><![CDATA[San Diego ]]></publisher-loc>
<publisher-name><![CDATA[Academic Press]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
