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Las firmas paleoatmosféricas en las hojas fósiles del neógeno
Science (New York, N.Y.)
|June 18, 1993
Resumen
Los estomas de las hojas disminuyen a medida que aumenta el dióxido de carbono atmosférico (CO2). El análisis de hojas fósiles revela esta relación como un bioindicador de los niveles pasados de CO2 durante los últimos 10 millones de años.
Área de la Ciencia:
- La paleobotánica es la paleobotánica.
- Ciencias del clima Ciencias del clima Ciencias del clima
- Ciencias del medio ambiente Ciencias del medio ambiente.
Sus antecedentes:
- El aumento de las concentraciones atmosféricas de dióxido de carbono (CO2) está relacionado con una disminución de la densidad estomática de las hojas.
- Este fenómeno se ha observado en vegetación reciente y experimentos controlados.
- La evidencia de plantas fósiles ofrece una perspectiva a largo plazo sobre esta relación.
Objetivo del estudio:
- Investigar el uso de las frecuencias estomales de hojas fósiles como un bioindicador para los niveles de CO2 paleoatmosférico.
- Para reconstruir las fluctuaciones del CO2 atmosférico del Neogeno tardío.
Principales métodos:
- Análisis de las frecuencias estomales en hojas fósiles de Quercus petraea.
- Aplicación de la relación conocida entre la densidad estomatal y la concentración de CO2.
Principales resultados:
- Las frecuencias estomales en hojas fósiles proporcionan un indicador confiable de los niveles de CO2 anteriores.
- Se estima que las concentraciones atmosféricas de CO2 del Neógeno tardío han variado entre aproximadamente 280 y 370 partes por millón en volumen.
Conclusiones:
- La frecuencia estomática de las hojas fósiles sirve como un valioso bioindicador para reconstruir los niveles históricos de CO2 atmosférico.
- El CO2 paleoatmosférico experimentó fluctuaciones significativas durante el período Neogénico tardío.
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