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Historia ambiental del cuaternario tardío del lago Valencia, Venezuela
Science (New York, N.Y.)
|December 18, 1981
Resumen
Los datos paleoclimáticos del lago Valencia, en Venezuela, revelan 13.000 años de historia climática. Las condiciones secas tempranas pasaron a un lago permanente con vegetación arbórea, seguido de episodios de secado exacerbados por la actividad humana.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Paleoecología Paleoecología.
- La geoquímica es la geoquímica.
Sus antecedentes:
- El lago Valencia, en Venezuela, es un sitio de baja elevación y baja latitud.
- Comprender su historia paleoclimática proporciona información sobre las dinámicas climáticas regionales.
Objetivo del estudio:
- Para reconstruir la historia paleoclimática de la región del lago Valencia durante los últimos 13.000 años.
- Para identificar los cambios climáticos pasados y su impacto en la vegetación y las condiciones del lago.
Principales métodos:
- Análisis de un núcleo de sedimentos de 7,5 metros del lago Valencia.
- Empleando técnicas químicas, paleontológicas y mineralógicas.
Principales resultados:
- Los climas secos prevalecieron desde 13.000 hasta 10.000 años antes del presente (B.P. ), con las marismas salinas.
- Un lago permanente con salinidad fluctuante y vegetación arbórea surgió alrededor de 10.000 años BP.
- El lago Valencia descargó agua en 8500 años BP, pero experimentó dos episodios de secado, este último intensificado por las actividades humanas.
Conclusiones:
- La historia del lago Valencia refleja importantes cambios paleoclimáticos en Venezuela.
- La vegetación moderna se estableció por 8500 años antes de Cristo. con la descarga del lago.
- Las tendencias actuales de secado están vinculadas tanto a la variabilidad climática natural como a los impactos antropogénicos.
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