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Published on: November 21, 2015
Floras terrestres: el mayor control de dióxido de carbono / oxígeno atmosférico de la fase tardía del fanerozoico
Science (New York, N.Y.)
|June 2, 1978
Resumen
La vegetación terrestre influye significativamente en el dióxido de carbono atmosférico y los niveles de oxígeno. Los cambios en los ecosistemas terrestres, como los que ocurren durante las transgresiones marinas, alteran la productividad primaria global, lo que afecta a las concentraciones de gases atmosféricos.
Área de la Ciencia:
- Paleontología Paleontología.
- Ecología Ecología Ecología.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- La vegetación terrestre ha sido históricamente un conductor principal de la dinámica atmosférica de dióxido de carbono y oxígeno desde la era Mesozoica.
- Los ecosistemas terrestres modernos, excluyendo tipos específicos, exhiben una mayor productividad por unidad de área que los ecosistemas marinos.
- Esta dominación terrestre en la productividad probablemente persistió durante gran parte del período Fanerozoico tardío.
Objetivo del estudio:
- Para analizar el impacto de los cambios en el ecosistema terrestre en la composición de los gases atmosféricos.
- Evaluar la productividad comparativa de los ecosistemas terrestres frente a los marinos en el tiempo geológico.
Principales métodos:
- Análisis comparativo de los ratios de productividad de los ecosistemas (productividad/área).
- Modelado de los efectos de las transgresiones y regresiones marinas en la productividad primaria mundial.
Principales resultados:
- Los ecosistemas terrestres generalmente muestran mayores proporciones de productividad / área que los ecosistemas marinos.
- La reducción de los ecosistemas terrestres (por ejemplo, durante las transgresiones marinas) conduce a una disminución de la productividad primaria global.
- La disminución de la productividad primaria resulta en un aumento del dióxido de carbono atmosférico y una disminución de los niveles de oxígeno.
Conclusiones:
- Los cambios en la extensión de los ecosistemas terrestres son reguladores críticos del dióxido de carbono y el oxígeno atmosféricos.
- Las transgresiones y regresiones marinas tienen efectos significativos y opuestos en la composición atmosférica debido a su impacto en la vegetación terrestre.
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