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Dinámicas a escala milenaria de las selvas tropicales del sur del Amazonas
F E Mayle1, R Burbridge, T J Killeen
1Department of Geography, University of Leicester, Leicester LE1 7RH, UK. fem1@leicester.ac.uk
Science (New York, N.Y.)
|December 23, 2000
Resumen
Las selvas tropicales amazónicas se están expandiendo hacia el sur en Bolivia debido a los cambios climáticos. Esta expansión, impulsada por la Zona de Convergencia Intertropical.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Ecología Ecología Ecología.
- La biogeografía es la biogeografía.
Sus antecedentes:
- Los límites entre la selva amazónica y la sabana son sensibles al cambio climático e influyen en la especiación.
- Comprender la dinámica a largo plazo de estas fronteras es crucial pero limitado.
Objetivo del estudio:
- Para reconstruir la dinámica de los límites de la selva amazónica en escalas de tiempo milenarias.
- Para determinar la extensión más meridional de la selva amazónica en los últimos 50.000 años.
Principales métodos:
- Análisis de los registros de polen del Cuaternario tardío del margen sur de la Amazonia.
- Reconstrucción de los cambios de vegetación pasados y cambios de límites.
Principales resultados:
- Los húmedos bosques tropicales de hoja perenne en el este de Bolivia se han expandido hacia el sur en los últimos 3000 años.
- El límite actual del bosque es la extensión más meridional observada en al menos 50.000 años.
- La expansión de la selva tropical se correlaciona con el aumento de la migración estacional latitudinal de la Zona de Convergencia Intertropical.
Conclusiones:
- Los cambios climáticos pasados, específicamente el forzamiento de Milankovitch que influye en la Zona de Convergencia Intertropical, impulsaron la expansión de la selva amazónica.
- Estos hallazgos proporcionan información sobre la historia ecológica y climática a largo plazo de la cuenca del Amazonas.
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