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Bosques del Holoceno en los desiertos del suroeste
Resumen
Los desiertos del suroeste de los Estados Unidos cambiaron de bosques a desiertos hace 8.000 años debido a la reducción de las precipitaciones invernales. Este cambio climático se quedó atrás de las tendencias globales porque el derretimiento de los glaciares influyó en los patrones climáticos.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Geología del Cuaternario Geología Cuaternaria
- Ecología Ecología Ecología.
Sus antecedentes:
- Los medios de las ratas de carga proporcionan valiosos registros paleoecológicos.
- Los desiertos del suroeste de los Estados Unidos experimentaron cambios climáticos significativos a finales del Cuaternario.
Objetivo del estudio:
- Para reconstruir las comunidades forestales del pasado en los desiertos del suroeste de los EE.UU..
- Para identificar el momento y las causas de los cambios de vegetación.
Principales métodos:
- La datación por radiocarbono de 29 medias de ratas de la manada.
- Análisis del material vegetal fósil dentro de los medios para inferir la vegetación pasada.
Principales resultados:
- Las comunidades boscosas se documentaron en los desiertos del suroeste hace menos de 10.000 años.
- Una transición sincrónica al desierto o pastizal ocurrió hace aproximadamente 8.000 años en los desiertos de Chihuahua, Sonora y Mohave.
- Causa inferida: un desplazamiento hacia el norte de la baja de las Aleutianas y la trayectoria de las tormentas invernales, reduciendo las precipitaciones.
Conclusiones:
- El cambio a climas no pluviales en el suroeste se retrasó en comparación con el hemisferio norte.
- El derretimiento de los glaciares continentales influyó en los patrones de circulación atmosférica, impactando el clima del suroeste.
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