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BOLETÍN DE LA SOCIEDAD GEOLÓGICA MEXICANA http://dx.doi.org/10.18268/BSGM2014v66n1a1 |
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Análisis de la lluvia de polen moderna de la cuenca de México: una herramienta para la interpretación del registro fósil
Socorro Lozano-García1,*, Alexander Correa-Metrio1, Laura Luna1
1 Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Delegación Coyoacán, 04510, México, D.F., México.
* This email address is being protected from spambots. You need JavaScript enabled to view it.
Abstract
Several factors affect the production and dispersion of pollen grains modifying the representation of pollen and spores in fossil records from sedimentary sequences. Analyzing these factors throughout the study of modern pollen rain contribute to the understanding of the fossil pollen spectra. Modern pollen rain from eight vegetation types following an altitudinal gradient from 2300 to 4329 magl in the basin of Mexico is analyzed by using statistical analyses. Pollen spectra from high elevation plant communities > 3800 magl were divided from low altitudes based on cluster analysis. Base on pollen composition the DCA distribute the plant communities in an altitudinal gradient and the probably density functions (PDF) are used to describe the pollen distributions along the altitudinal gradient. Pollen taxa with low percentages characterize the low altitude sites with PDFs similar to the parental taxa. Pinus, Poaceae and Asteraceae show ample altitudinal ranges and their PDFs reflect a pattern comparable to the parental taxa while Quercus, Alnus, Salvia and Salix with narrow altitudinal ranges have PDFs that indicate pollen transport to higher altitude sites. The presence of Mimosa, which present a well define PDF, can be used as indicator of paleoenvironmental conditions in the fossil pollen sequences in the basin of Mexico.
Keywords: Pollen, probability transfer functions, ordination, cluster analysis.
