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Modelo de fijación de carbono en alfombras microbianas desde hace 3.500 millones de años hasta la actualidad
L J Rothschild1, R L Mancinelli
1Solar System Exploration Branch, NASA-Ames Research Center, Moffett Field, California 94035, USA.
Nature
|June 21, 1990
Resumen
Los primeros años de vida.
Área de la Ciencia:
- Paleontología Paleontología.
- Ecología Ecología Ecología.
- La geoquímica es la geoquímica.
Sus antecedentes:
- La fijación biológica del carbono es crucial para el ciclo global del carbono y la ecología.
- Los stromatolitos, alfombras microbianas fosilizadas, registran la fijación temprana del carbono desde hace 3.500 millones de años y eran abundantes en el Proterozoico.
- La abundancia de estromatolitos disminuyó, posiblemente debido a la depredación, la competencia o los cambios ambientales.
Objetivo del estudio:
- Investigar el impacto de los niveles de dióxido de carbono (CO2) atmosférico en las tasas de fijación de carbono biológico en antiguas alfombras microbianas.
- Explorar el papel de la limitación del carbono en el declive de los estromatolitos durante el Precámbrico.
Principales métodos:
- Utilizó alfombras microbianas modernas como análogos de los antiguos estromatolitos.
- Comparación de las tasas de fijación de carbono bajo diferentes concentraciones de CO2 atmosférico, simulando condiciones pasadas.
Principales resultados:
- Las tasas de fijación de carbono fueron más altas bajo niveles elevados de CO2 atmosférico, características de la Tierra primitiva.
- La fijación microbiana de carbono en el mate probablemente no estaba limitada al carbono en el temprano Precámbrico.
- La fijación de carbono se limitó a medida que el suministro de carbono inorgánico disminuyó hacia el final del Precámbrico.
Conclusiones:
- La disminución de la disponibilidad de CO2 puede haber contribuido a la disminución de los estromatolitos.
- Los cambios en los niveles de CO2 atmosférico influyeron significativamente en la fijación temprana del carbono biológico y en los ecosistemas microbianos.
Palabras clave:
El ARC del Centro de la NASA en el Centro de la NASA.La disciplina de la NASA es la exobiología.El número de la disciplina de la NASA es 52-50-50.Programa de exobiología de la NASA Programa de exobiología de la NASA.Más Videos Relacionados
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