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Estepa-tundra del Ártico: una perspectiva de los yukon
Science (New York, N.Y.)
|June 20, 1980
Resumen
Los datos de polen de Beringia oriental refutan la hipótesis de la esteppetundra. Los hallazgos indican que una tundra ártico-alpina escasa, no un prado, existió durante el último período glacial.
Área de la Ciencia:
- La paleobotánica es la paleobotánica.
- Geología del Cuaternario geología cuaternaria.
- Paleoecología Paleoecología.
Sus antecedentes:
- La hipótesis prevaleciente sugiere un steppetundra o un ecosistema de pastizales en el este de Beringia durante el Pleistoceno.
- Se pensaba que este ecosistema apoyaba a la megafauna extinta y a las primeras poblaciones humanas.
Objetivo del estudio:
- Para reconstruir el paleoambiente del este de Beringia utilizando la estratigrafía del polen.
- Para probar la hipótesis de la esteppetundra / pastizal asociada con los vertebrados extintos y los primeros humanos.
Principales métodos:
- Análisis de la primera estratigrafía confiable y seguramente fechada de polen completo y tardío de la glaciación de Beringia Oriental.
- Interpretación de la flora fósil y los datos de la afluencia de polen.
Principales resultados:
- La estratigrafía del polen contradice la hipótesis de la esteppetundra o de las praderas.
- La flora fósil indica una vegetación ártico-alpina.
- La baja afluencia de polen sugiere escasa vegetación.
Conclusiones:
- Se rechaza la hipótesis de una esteppetundra o pastizal en el este de Beringia.
- El paleoambiente era probablemente una tundra escasa, comparable a la moderna vegetación de hierbas y campos de cultivo.
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